Author Topic: Grizzly G9249 Lathe Improvements and DRO install  (Read 10309 times)

Offline propforward

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Grizzly G9249 Lathe Improvements and DRO install
« on: February 13, 2022, 12:17:06 AM »
Well, I was all set to start my next engine, and had the castings all out, and I'd been perusing the drawings all week. Here it is = a PMR #4.



But, late last year I ordered a magnetic DRO kit from DRO PRO's and I think it makes more sense to install that and tune up the lathe a bit before starting. I did have a huge lathe upgrade planned, with new 3 phase motor and VFD, but I have decided to go one step at a time. First step is the DRO and to beef up the base. First - DRO.

I had good experience with DRO PRO's on my mill, so decided to go with them again. I agonized over 2 and 3 channel, but I could not see a good way to get a third axis on my compound easily, and I don't think that is so essential anyway, so 2 channel it is. I have a small standalone digital scale for the tailstock.

Here's my lathe, minus the back splash, removed for the install.



DRO box - they pack their stuff well.





The scales are very nicely protected.



The readout:



I'm not going to go into intricate detail on the install, because the DROPRO's website has very thorough step by step video "how to's" and instructions. The really nice thing about the magnetic scales is how easy they are to cut to length, so I can get the cross slide nice and neat.

Here's a close up of the installation area. Unfortunately I'm going to lose the lock - but it is not a very good lock anyway, so I'll come up with a better one.



The DRO kits come with an assortment of aluminum brackets, that are more or less "universal". In practice I have found they usually form a decent starting point, but you get the best out of them if you just accept you'll most likely have to machine them to fit, or make your own new brackets.

For the cross slide I drilled and tapped two M6 holes in the saddle, and mounted this chunky L bracket. It is deliberately off center between the bed rails to allow the cross slide to go full travel in both directions without the read head hitting the ends of the scale.



Being able to drill the scale mounting holes in the mill is nice. Won't be able to do that on the saddle scale.



View of the scale before cutting to length - here I have removed one end cap and marked out the cut line.



I just cut the excess off with my bandsaw, which works just fine. Then it's a matter of drilling and tapping a couple of holes for the mounting screws.

fast forward - here is the scale installed, and I've milled down the top of the bracket to hold the read head. Next step will be to drill and tap two holes in the top of the bracket to mount the read head, and the cross slide is pretty much done, except for alignment. Hope to get that done tomorrow and also install the saddle scale and sensor.

« Last Edit: February 13, 2022, 12:20:52 AM by propforward »
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #1 on: February 13, 2022, 12:20:53 AM »
oh oh oh!   watching along!   I'm waiting for my phone call for them to tell me it's delivered!!!!

 :popcorn: :ThumbsUp:
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #2 on: February 13, 2022, 12:47:43 AM »
Did yours not show up yet? I thought you ordered it a while ago?
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #3 on: February 13, 2022, 12:53:54 AM »
Right after new years    They said they'd be expecting them in late February....and they would call me.

Dave
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #4 on: February 13, 2022, 01:06:20 AM »
Oh got it, yes supply chain issues. That stinks but hopefully not long now!
Stuart

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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #5 on: February 13, 2022, 11:21:30 PM »
Todays progress. There was some, even after enjoying some red wine last night.  :wine1:

First of all, drilled and tapped the mounting block and did a test fit of the read head.



Happy with that. Also happy that when the time comes I will be able to fit the extruded aluminum shield over the set up. I'll need to trim the lower lip off and cut it to length of course, but the top of the cover sits slightly sub flush to the top of the cross slide so that the compound can rotate without interfering.



My kit has a 40" scale for the saddle, and I thought I would be able to just mount the whole thing in place without trimming, but I could not get the drill past the drive motor on the headstock end, so a couple of inches had to come off.



I then mounted it in place on the rear of the lathe using 1-2-3 blocks under the bed rails, and then transfer punched the drill locations.





That worked a treat for getting the mounting hole locations. I am planning on mounting the scale directly to the rear of the bed initially - I think I can shim the scale to get it flat along its length. If not, then I'll put a couple of spacers behind the scale, and mount the scale on a piece of stout aluminum bar instead,

For the mounting bracket, I made use of some of the bits in the install kit. This was longer than needed.



And customizing it is no problem of course.



The read head is mounted on a sliding bracket attached to the end of the modified mount bracket.







That is fine I guess, but it's not very elegant. I might either trim the lower bracket, or just make my own one. It just looks a bit clunky - not that you see it anyway - and frankly that may be the deciding factor. Once the install is finished and working I may just not see it and so it won't matter any more.

Speaking of working, having got this far I hooked up the readout temporarily to do a test.



It works! I wanted to do this in case there were any issues anywhere so I could address them, but looks OK. Everything is loose at the moment so I did not bother doing any accuracy tests, just turned the handles a bit and checked the numbers counted.

That's it for the DRO install for the time being - I'm not fine tuning the set up just yet, until I have performed the next upgrade. Sooooooooooo....................

Stuart

Forging ahead regardless.

Offline simplyloco

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #6 on: February 13, 2022, 11:30:20 PM »
I was anti DROs for many years, until i fitted one..
Strong minds discuss ideas, average minds discuss events, weak minds discuss people.” ― Socrates

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #7 on: February 13, 2022, 11:31:35 PM »
Voila!



I popped the lathe off of its stands using my engine hoist. No pictures of the process, because once I have the thing airborne I like to move it and set it down as quickly as possible. Don't need one of these moments:



Anyway, the next upgrade is to beef up the mounting of the lathe to the cabinets. The cabinet tops are about 3/16" thick steel, and it is very easy to deflect the cabinet top by leaning on the lathe - which can't be good  for keeping the bed straight in use. I can also feel the lathe oscillate gently as it runs.

So I had a couple of 1" thick steel plates waterjet cut at work, to place on top of the cabinets. I have sized the plates to be larger than the outside dimensions of the cabinets. In these pics I am just checking the holes line up.





Quick fit up of the chip tray.



While the tray is off, I intend to modify it. Some years ago I modified a brass bulkhead fitting to put in the tray corner, to return coolant to the reservoir. It worked, but it's a bit - I don't know - crap I suppose.





Now that I have some rudimentary welding skills I want to weld a barb fitting to that corner, and also cut a hole in the chip tray and weld a tube dam in place, for routing the coolant hose and the DRO cables through the tray and to the readout.

That's as far as I got. I now need to check how flat the plates are - I know they are not flat, but if they are really bad I'll have to fly cut them. Then I want to paint them, and of course mod the chip tray. Hoping to get that done in the evenings this week so that I can work on reassembly next weekend, and finesse the DRO install. While I am typing, here is a view of the saddle scale on the back of the lathe, since I can get a look at it now:



Pleased with it so far.

 :ThumbsUp: :ThumbsUp:

But now, it's time for some QI and  :wine1:

Stuart

Forging ahead regardless.

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #8 on: February 13, 2022, 11:34:44 PM »
I was anti DROs for many years, until i fitted one..

I know what you mean. I was doing OK without, but what the mill DRO has revealed to me in terms of backlash has been a game changer - my parts are just more accurate because that huge variation has been taken out - not to mention how much the table moves when I lock it, so having one has been really helpful. Hoping having one on the lathe will be similarly helpful.
Stuart

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Offline Craig DeShong

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #9 on: February 14, 2022, 05:20:15 PM »
Stuart

I’ve been thinking about a DRO for a while.  My lathe is a later model than yours (G4003G) but it looks pretty much the same.  You’ve done a good job of installing the scales where they are out of the way and your setup would probably work for my lathe also. 

I’ve gotta say that this post has certainly moved me further along the path of acquiring and setting up a DRO on my Grizzly.

For the most part, I use a dial indicator that clamps to the ways and measures the travel of the saddle.  This works well for measurements under an inch, but can be a pain for saddle travel over an inch.

You do have me rethinking. :thinking:
« Last Edit: February 14, 2022, 05:28:04 PM by Craig DeShong »
Craig
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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #10 on: February 14, 2022, 08:09:37 PM »
I'm still on the waiting list for mid March delivery..... :-[

Dave
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #11 on: February 14, 2022, 11:59:33 PM »
Hi Craig,

I looked up your G4003G and it does look to be exactly the same lathe in terms of bed and saddle, basically it has a gearhead rather than belt drive and back gear, and the very nice addition of a camlock spindle (wish I had one of those), but otherwise I would think the DRO would fit the same way. These magnetic scales do make it very easy. I do know someone who successfully cut down some glass scales, so it can be done, but it takes a lot more care I think, and the lightweight cross slides on these lathes don't offer a lot of room. The magnetic read head fit in the available space well. I'm glad this post has provided some food for thought that way.

Dave - I sure hope your DRO shows up sooner rather than later! I know how keen you are to get that addition in place.

I was hoping to work more on the upgrades tonight - alas I have to do actual "work". Bah! Never mind, I have Friday off so that I can have a 3 day weekend and hopefully power through and get the lathe back on the cabinets.
Stuart

Forging ahead regardless.

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #12 on: February 19, 2022, 11:21:35 PM »
A little progress today, although not as much as I hoped.

This piece of very nice sanitary tubing came home with me, fetched out of one of the scrap bins at work. It was a test piece for dialing in the orbital welder. I only need a small chunk to make a tunnel through my chip tray for the DRO cables and the coolant hose to go.



And this is where it is going. I tried using a hole saw to cut this out, but had to resort to cut off wheels. The Chinese steel in the chip tray was tougher than the Chinese hole saw.

 

There it is.



The hole in the lower corner is where the coolant drain goes. A stainless steel barbed fitting was supposed to arrive during the week but it is lost in the mail somewhere. So that has to wait a bit.



Well I did say that my welding skills are rudimentary. No matter, this will work fine.

Then a bit more set up on the long axis scale. It's much easier to get at while the lathe is off the bench, so I started getting it trued up. The spec is .004" flat over the full 40" length.

I started by clamping the scale down tight, and scanning a dial indicator across the whole length, noting the changes in height relative to a zero position. I chose the highest point of the scale as zero, which happens to be the headstock end. From that point on the scale dips down.







It's pretty easy to see that the clamping points are bowing the scale in, so the next step was simply to shim at the clamp points according to the measured bow. I had the scale within .015" very quickly.

My plan now is to get the clamp points flat within the .004", and then add shims at any other dip points as needed.

It is also necessary to get the rail parallel to the direction of travel within .004" over the 40" span. I actually had that right off the bat from setting it with the 1-2-3 blocks. I'm sure I'll need to tweak it after levelling, but that should not take long.

After that it will be time to get the lathe up on its new steel plates, once the chip tray is finished and the paint dry. I may see if I can find a stainless barbed fitting locally tomorrow. I'd like to get the chip tray painted during the week so I can set the lathe in place next weekend and start de twisting the bed and getting the headstock parallel again.
Stuart

Forging ahead regardless.

Offline Craig DeShong

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #13 on: February 19, 2022, 11:41:35 PM »
There is a lot to do to get this “right”.  You can’t just slap the scale on the back of the lathe bed and expect accurate measurements.

My Bridgeport mill came with an ancient DRO that started loosing segments in the display shortly after I received the mill.  I got tired of watching the DRO so I would know if the final number was a six or an eight (for instance) so a replacement was warranted.

Even with the “help” of a previous DRO setup, I spent multiple days installing the new DRO on the mill.  Looks like you are going to have an accurate set up when you finish. :cheers:

An interesting side note: my mill came out of Cooper tools in  Apex, North Carolina and I have a friend who spent his career there in the tool room.  He tells his first task, when hired, was to install that original DRO on my mill.
« Last Edit: February 19, 2022, 11:45:38 PM by Craig DeShong »
Craig
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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #14 on: February 20, 2022, 11:10:50 AM »
It's nice to have the lathe off the bench for sure!!    That's going to be far more difficult for me as I don't have room to take mine off at the moment...gonna need to think about that very hard...I too will also have the 40 inch scale...

tell me about the "interstitial clamps" that appear to be a form of toe clamp?   Did you make those Prop?   Can you clamp on to the scale at points other than the ends?


Dave
« Last Edit: February 20, 2022, 11:52:49 AM by steamer »
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #15 on: February 20, 2022, 02:30:24 PM »
Craig,

You're absolutely right - it is vital to get the scales properly level, and the read heads mounted parallel to the scale in order to get accurate results. Although I understand that these magnetic scales and readers are amazingly forgiving. I have seen some photos of installations that looked decidedly questionable, but the users claim good results. Of course, what you need for accuracy, resolution and repeatability in the home shop vary user to user, therefore what gets reported as "good" has to be taken a bit with a pinch of salt sometimes. I like to at least give it my very best shot in the installtion to get everything properly level to get the best out of it. I think this set up should work.

That's great that you have that history on your Bridgeport, very satisfying to know when / where / how it was set up and used. I have had a chance at a couple of Bridgeports but the history was so questionable I let them pass. They looked kind of beaten up - but that could easily have been all cosmetic. I just couldn't take the chance.

Dave - yes indeed the scales have a groove feature along both edges, and these little toe clamps are made to fit in that groove. DRO PRO's supply one pair of clamps with the 40" scale. I had another pair left over from my mill install, so decided to use the extra clamping.

The directions supplied with the scales have a suggested 3 point mounting scheme for uneven surfaces, where you put a mounting plate behind the scale at the ends and in the middle, leaving the spans unsupported. The advantage being that you can machine the mounting pads individually to get the scale mounting surfaces co planar. That should work, but I am not certain about the unsupported spans staying flat. Another way might be to take the same approach, but also then mount the scale on a very stout and flat bar which in turn mounts to the 3 blocks.

Those are back up plans that I have in mind - I think my shimming approach should work. If for some reason I cannot get the scale flat enough then I can always start again with one of the other approaches. The cross slide scale is mounted on a ground surface, so that one is easy.

Also, I didn't make much mention of it but as I machine the read head mounting brackets, I am machining them at angles to account for any draft on the lathe castings, and present the read heads properly to the scale. I think the more care taken to get this right, the more accurate and repeatable the readings will be.

Stuart

Forging ahead regardless.

Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #16 on: February 20, 2022, 08:54:05 PM »
Hey Stuart,

I plan on making 5  3"plinths.   The end 2 will be for bolting on, while the center 1 will have a jack screw, and I think I'm going to grout the scale in with thickened epoxy  (JB  weld )


I think I'm going to do it like the guy who mounted them on his SB with a dedicated drill sled and get them all the same depth from the inner V way
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #17 on: February 20, 2022, 10:56:35 PM »
Oh man - that's a brilliant idea. At first I was thinking "if only I could mount the lathe bed on the mill and machine some flat surfaces", but could not make the leap to a similar, but differently implemented idea.

That might now be my preferred back up plan if my shimming approach doesn't work out. Your way will likely be more solid - I do worry about shims shaking loose over time in some locations. Guess I'll see what happens.  :zap:
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #18 on: February 20, 2022, 11:07:34 PM »
I'll sketch up what I have in mind....and share it....be patient....

Dave
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #19 on: February 20, 2022, 11:14:16 PM »
I'd appreciate that very much. And no rush, I'll keep going with what I have, but removing it and reinstalling it is really not that big of a job.   :ThumbsUp: :ThumbsUp: :ThumbsUp: :ThumbsUp:
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #20 on: February 20, 2022, 11:31:45 PM »
Heres kinda what I had in mind    Im considering it as 2 pieces .   A U shaped nest that you put the jB weld in and a stand off busing with a screw in it.

I would probably put a strip of packing tape down the middle to cover the head of the screw,    I don't suspect the mag strip is going to go bad and need changing out, but if it did, you could easily cut either side of the bracket and spin it off.

Dave
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #21 on: February 21, 2022, 12:15:54 AM »
I like that a lot. I really like that a lot. That will make for a very solid install. Going to give this some serious  :thinking:
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #22 on: February 21, 2022, 12:23:37 AM »
I am reluctant to give a design to someone for something that I haven't already proved out.   That said.   Think very hard about it, and test what ever you can before you do it.

Dave
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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #23 on: February 21, 2022, 12:57:15 AM »
To work correctly, the scale has to be grouted up and down as well as in and out.   That way it's in a zero stress state when the epoxy kicks

Dave
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #24 on: February 21, 2022, 01:28:10 PM »
So the epoxy is to secure the scale in position once it's levelled? Do you see any particular advantage to that over just using levelling screws or mechanical fastenings?

I'm now quite disappointed in my scale mounting. As I look back at it on this thread it just looks very half baked. I think I would like to take the 3 plinth approach, but I'm interested in mounting the scale to a stout, flat bar, which is in turn mounted to the 3 plinths. I have to do a bit of measuring and see how flat an aluminum bar can be held when clamped on 3 points. I think extruded aluminum bar is pretty straight.

I should have thought this through more carefully before demounting the lathe. I think I will need to replace the lathe to make some parts to mount the scales. However, removing the lathe is actually not all that difficult.

EDIT: In reviewing the DRO PRO's customer gallery again, it is very common to have these long scales just mounted on 3 points, with no supporting bar behind. I'm now doing what I always do and second guessing myself, and getting in a confuzzle.  :headscratch:

It's a good time to have to leave the project for a bit and return to the real world. But I'm pretty sure I'm going to start over on the long scale. This little bit of wheel spinning usually obtains a result I'm happy with though.
« Last Edit: February 21, 2022, 01:45:24 PM by propforward »
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #25 on: February 21, 2022, 02:32:48 PM »
The center support is to prevent flexing.   To do that I'd use a grout in my concept.    You've built may wonderful projects Stuart.   Don't second guess yourself.   It'll be fine!

Dave
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #26 on: February 21, 2022, 02:49:51 PM »
Oh I understand now. You jack the center into place in setup then grout secure - got it. Makes sense.

Thanks for the encouragement and following along! I appreciate it a lot.
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #27 on: February 21, 2022, 02:55:56 PM »
Oh I understand now. You jack the center into place in setup then grout secure - got it. Makes sense.

Thanks for the encouragement and following along! I appreciate it a lot.

Yup  with screws top an bottom .   Then once set put some epoxy in there and set it back down one last time..    Set it up dry a couple of times to make sure it will repeat, and take your time.   The epoxy won't be drama if you do the set up well.

But lots of ways to skin the cat.....   Just get after it.      8)
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #28 on: February 26, 2022, 11:04:02 PM »
Right so, welcome back to Stuart ties himself up in knots.

I didn't get to work on this during the week, so first order of business was to finish up the chip tray, so the paint can dry while I work on scale mounting.

I have to turn the gaping hole in the lower right corner into a 5/8" barbed hose fitting.



Which I did by drilling and milling a suitable size hole in a piece of 1/8" stainless I had lying about.



I have to admit - reasonably happy with the welding on this.









Got it a little too hot at this point.



Then cleaned it up with acetone and rattlecanned it with some hammer finish paint.





I think my welding and paintwork is at least as good, and probably better than the original Chinese finish.

This is a much neater solution than my original bolt on brass fitting.



Anyway, while the paint dries, back to the long scale install.

The magnetic scales have jack screws each end, so I spent a little bit of time tweaking those to see if I could get the scale straight - and I expect I could have got it there, but it was taking a lot of time to make minor improvements, and that side of the lathe is just so non flat that I didn't feel it was a robust solution, so I decided to move on to a 3 point mounting block solution.

First off, I thought I'd do a measure of the straightness of the scale itself, just to reassure myself.

 

So what I have there is the scale sat on two 2-4-6 blocks. The scale is not clamped down. I rest it up against a 1-2-3 block in the vise, and position a DTI on the scale. Then I gently fed the scale back and forth, lightly holding it on the 3 blocks. I did it this way because I wanted a feel of straightness in an unrestrained fashion. It is flat within .004" over the full length using this method - which I accept is not perfect. But the scale does not have significant bow in it. If I can make 3 mounting positions that are co planar then this scale can be mounted flat.

Stuart

Forging ahead regardless.

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #29 on: February 26, 2022, 11:09:15 PM »
The kit comes with a variety of brackets, and included in the kit are a couple of these black mounting blocks. They have jacking screws in the corners and are made to hold the scale at the ends.



I set up the first block and got it level relative to the carriage travel. I did then mount up the scale - and already it is more straight than I got with the prior method. However, jacking the blocks around with the scale on is a bit difficult. I have there fore removed the scale again, and I'm simply levelling each block in turn, referencing them back to the first one. After that it should be very simple to get the scale mounted and straight.

That's where I'm at anyway, and I feel much better about this as an installation method.

I'm about done for the day, and my wife just texted me saying that it's time for stiff rum drinks, so I'll round off the days activities with a look at my lovely new Aloris toolpost.



I've been trying to lay my hands on a used one, but at auction they seem to sell for barely any less than a brand new one. So I went that route.
Stuart

Forging ahead regardless.

Offline Kim

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #30 on: February 27, 2022, 03:58:03 PM »
Boy, you're really doing this lathe project up right!  Nice welding on your chip/coolant tray too, I might add! :)

Kim

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #31 on: February 27, 2022, 11:04:21 PM »
Thanks Kim. I'm probably more proud of my little bit of welding there than I should be, but hey got to take satisfaction where you can.

Having drilled and tapped all the holes in the bed that I think I need, I got a bit fed up of stooping down to work on the machine, so today I put it back up on the cabinets.



Happily I got the locations of the mounting bolt holes in the new steel plates right, and I easily got a bolt in all 6 mounting locations. The lathe isn't bolted down yet, I just placed bolts so I knew they would fit. I still have to straighten the bed, but all in due course.

I've been a bit disappointed in the whole Z axis scale affair, so I decided to leave that for a while and do a few ancillary things. So I mounted the readout. First made a simple plate for the mounting block. I did this rather than screwing the block directly to the wall, because the block has jacking screws in case you want to tweak the readout angle.







This is what the tube is for - both read head cables and the coolant hose will run through here.



I aligned the X axis scale - this one is easy since it is mounted to a flat, ground surface. Being so short it is very simple to get it to a point where the indicator needle doesn't move at all.



Then put the read head on and gave it a try.



Works! Had to set up the readout for the 1um scale, and to read in diameter mode, which is simple. Seems to read properly when compared to the hand wheel, after the Z axis scale is installed I'll do some proper accuracy tests.

For now I'm happy - except for dropping my little adapter for my interapid DTI which has bounced off into the recesses of the shop somewhere. So finding that is the next mission. D'oh!
« Last Edit: February 28, 2022, 12:33:39 AM by propforward »
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #32 on: February 27, 2022, 11:34:56 PM »
Still watching Stuart!    I like the approach on the Z axis.     makes sense to me!!!

Dave
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Damned ijjit!

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #33 on: February 28, 2022, 12:31:53 AM »
Thanks Dave, I think it will work. One of the reasons for getting the X axis up and running now is that I can use that to aid in measuring coplanarity of the 3 pads. That’s the next phase! But I have also just had a thought that my tapped holes in the bed might not be perfectly positioned - and could be inducing bow in the scale if too close together. I did see some potential evidence of that when I was dry fitting. So I’m going to slightly slot the bolt holes in one end pad to allow for that.

If this doesn’t pan out maybe I’ll strip the machine down, take the bed to work and have real machinist dust off a flat strip on one side.

 :facepalm:

I should really post these threads AFTER I am done, because then I could leave out all the “wrong turns” and I’d look like I know what I’m doing.

 :naughty:

That said, I don’t mind revealing some pitfalls for others who may benefit later on.
Stuart

Forging ahead regardless.

Offline Kim

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #34 on: February 28, 2022, 01:11:00 AM »
I should really post these threads AFTER I am done, because then I could leave out all the “wrong turns” and I’d look like I know what I’m doing.

 :naughty:

That said, I don’t mind revealing some pitfalls for others who may benefit later on.
Definitely!   I get so much more out of a build thread where someone takes me step-by-step through what they did, INCLUDING the wrong turns, what they learned from it, and what they did differently the second/third/nth time through.  I try and do that on my threads and I really appreciate it on others' threads too.  I find them SO much more instructive and interesting that way.

So, thank you for taking the time to document your journey and walking through your thinking at each stage.  I for one really appreciate it!

Kim

Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #35 on: February 28, 2022, 01:41:00 AM »
Nope!!! Publish warts and all!!!  That way I get to make NEW mistakes!!!!

Dave
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Offline Hugh Currin

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #36 on: February 28, 2022, 03:49:04 PM »
Stuart:

Definitely document the build as it happens. To just present the solution without the proof isn't nearly as interesting. Like seeing a polished pretty picture of an engine (boring) vs how it was made (interesting) vs how it was made including all the problems (instructive). Thanks.

I had though the hole in the chip pan was for coolant. But it will be hard to put a drain tube on the fitting with the cables already going though. Was the intent an access for the wires?

Thanks for the log.
Hugh

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #37 on: February 28, 2022, 03:55:05 PM »
Thanks all, I do appreciate the encouragement. The log is certainly more interesting when everything that happens along the way is included. Fun to look back on as well - I've read back on a couple of old threads of mine and have raised my eyebrows a few times ( I did what?!!).

Hugh,

The big center tube is only for cables and hose. What I used to do with the coolant hose was run it out under the backsplash to the coolant reservoir. In that situation though, coolant runs down the back splash, onto the hose and then drips down onto the floor. The idea here is that coolant drips off the back splash away from the through tube, so it doesn't have a path down the outside of the hoses and cables. This may work - but then some coolant may find its way onto the cables anyway, but I have those set up to be away from where the cutting and splashing takes place. We shall see!

The coolant drain in the corner of the chip pan was placed there because that's where coolant tends to collect when I'm running it - hopefully it still does after all these mods.
Stuart

Forging ahead regardless.

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #38 on: March 01, 2022, 01:32:19 AM »
Panic over - the adapter has been found. I know you were all climbing up the curtains in frustration. It was under the shelf where the chucks are stored.

The time honoured trick of leave it and come back in a day worked - found it within 2 minutes.

If this hadn't worked, the next sure fire solution would be to buy another one. The missing thing usually leaps into your hand then.

Stuart

Forging ahead regardless.

Offline ShopShoe

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #39 on: March 01, 2022, 02:20:00 PM »
Thank You for the reality check by posting your note about the missing adapter. I am glad you found it!

I have a note: "Find the missing ER11 Collet"  Note's been there for over a year. Bought a new one.

ShopShoe

Offline gary.a.ayres

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #40 on: March 01, 2022, 08:55:29 PM »
Wow... the DRO will be a great enhancement to your lathe.
And when you eventually add the 3-phase motor and VFD it will be superb!
gary

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #41 on: March 05, 2022, 09:27:35 PM »
Thanks Gary, I'm already enjoying it and I'm not done installing it yet (still faffing about with it).

Today I slotted the one end mount.



Then I was getting ready to level up the Z axis mounting pads, and realised I needed to make something to do it. I'll come to that in a bit, but what it meant was that I needed to bolt the lathe down. I figured for the simple part I needed to make I didn't need to get the twist out of the bed, so I boltd the headstock down. However when I checked it out of curiosity with my machinist level, the lathe was already less twisted on the new steel plates than it was in a similar condition without the plates.

I was so excited by that that I shimmed the tailstock end and got the bed straight.

Headstock



Tailstock



So the lathe is straight, but slightly sloped front to back, by about 12.5 thou per foot. I'm not concerned about that, since the bed is now straight. The steel plates also hold the lathe very solidly.

So I fired it up and I can now run the lathe at full speed - 1200 rpm - with significantly less vibration than before. I am incredibly happy with this. There is still some vibration to address from belts and motor, but I am now comfortable using the machine over its full speed range - prior to this I really was not comfortable running it over 500 rpm, which was a hindrance. Not only that, but I was able to take much heavier cuts at these speeds than I have ever done before with no observable detriment to surface finish of the part.  :ThumbsUp: :ThumbsUp: :ThumbsUp:  :cartwheel:

So I was just trying it on some pieces of material, and I made this thing.



Wassat? And wassit for?

Well, it's to hold my DTI so that I can level the Z axis scale relative to the cross slide.





Now - it's a little bit delicate, but it works great. I can use the height gauge to move the DTI up and down to repeatable locations, and the saddle to traverse the pad, and then the cross slide (with DRO at this stage) to check the X axis dimension.

This may seem like a lot of messing about, but I got the end pad levelled very quickly, and soon after had the center pad level to the end pad - vertically and horizontally.

You do have to be patient, and you have to keep zeroing the X axis and re zeroing it as you move the DTI up and down, to be sure you are not moving things about falsely, but it worked. I did also check repeatability in one spot before relying on it too much.

So I'm closer now - I just have the far end pad to level now, and I can mount the scale again.  :ThumbsUp:

Needed a break, so I thought I'd write this intermediate blurb.
« Last Edit: March 05, 2022, 09:34:10 PM by propforward »
Stuart

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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #42 on: March 05, 2022, 11:33:08 PM »
Success! The Z axis scale is straight and level, no bow in it. That is satisfying. A quick fit up of the read head had it counting up and down nicely. The mounting bracket now needs some work, my original one no longer fits because I ended up mounting the scale at a different height. So that is tomorrows project. That's all for today - good progress and I'm very happy with the improvements.
Stuart

Forging ahead regardless.

Offline gary.a.ayres

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #43 on: March 06, 2022, 07:47:56 AM »
It's a great feeling to see that display doing its counting thing for the first time, is it not?  :ThumbsUp:

Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #44 on: March 06, 2022, 06:15:37 PM »
Looks great Stuart!     Did you end up with a center support?  or just the ends?

Dave
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Damned ijjit!

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #45 on: March 06, 2022, 10:12:12 PM »
Thanks Gary and Dave,

It is indeed a great feeling to see the numbers on the readout - a sign of getting near the end hopefully.

Dave, I did use the center support in the end. I don't know that I needed it - after levelling the 3 pads and getting them co planar, when I mounted the scale it (vary satisfyingly) sat flat against all 3 pads, so I suspect the center one is just gilding the lily a bit. That said, a little more support behind the scale is no bad thing.

Some pics of todays work.

I started off making a mounting block for the rear side of the saddle. The backside has a draft angle on it, as it is a raw casting. I measured that by using my height gauge again in conjunction with the X axis DRO, and just measured the change in X over a 1 inch height change.

Pretty easy maths when one of the sides of the triangle is 1.000.   ::)



Anyway, I machined up a little block





You can perhaps make out the angle on the side on the right in the picture.

Bolted in place this matches the saddle very nicely, and then it's just a matter of setting height and clearance to the scale using the supplied shim.



I modified one of the supplied covers to fit the cross slide and give it some protection:





The compound slide does clear the shield screw when being swung around.



Did some tying up of the cables. This is a temporary arrangement while I see how it works, I may adjust the cable routing a bit, but this seems to be working OK.



I also mounted the Z axis cover. I needed a couple of short spacers to do this. Horrible pic, sorry.



This one is better and shows how the cover protects the scale and the read head.



Read out:



Very nice to get to this point.

I'm not done yet though. Punchlist of remaining items:

Add ground cable from read out to the lathe.
seal the lathe feet to the chip tray with silicone sealant
Finish adding cable mounts to support the coiled bundle behind the headstock (there is usually a bit of extra cable with these universal kits).
Check lathe for taper and adjust as needed.
Add a DRO to the tailstock. I bought a 4" battery powered one from Shars. I sort of regret not getting a third axis but this route was a LOT less expensive and I think it will work great.



I also now have a new space to use - so I think I'm going to weld up a set of shelves to go under the lathe for holding some of the tooling.



I also have to figure out how to mount the backsplash. The original mounting points are behind the Z axis scale, and in any case the lathe sits 1" higher up so the backsplash would now interfere with my shelf. But I think a set of mounts for that will be quite simple to make.

That's it for today though. A quick check of the travel using a 2-4-6 block and a DTI to zero the saddle position showed that the DRO is reading correctly. So I am well pleased with that!
« Last Edit: March 06, 2022, 11:18:39 PM by propforward »
Stuart

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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #46 on: March 06, 2022, 10:18:39 PM »
And one major thing to finish I forgot to mention - there is no lock on the cross slide. This is a must fix. I figured out a plan today, and it will require me to dismantle the cross slide and machine a tapped hole from the top, then I think I can put a lock screw in that will push down on a brass pad on to the top of the fixed part of the cross slide to lock the assembly. It won't push down on the ways, but on the machined area below the moving part of the cross slide. It's difficult to explain but I'll take pictures when I do it of course. I think it will lock the slide better than the factory lock. I also need to attend to the tapered gib, which I discovered comes free at certain positions of the cross slide travel, causing some play. It could easily cause inaccuracies, and possibly be part of the culprit for some chatter.
Stuart

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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #47 on: March 06, 2022, 11:54:44 PM »
Glad you got it done!  The only install issue I see with my SB9 is the gib screws will be coverd I think.    I might get away with it if I change to square head screws or something.....I'll noodle that!

Nicely done sir!   I can't wait to get a phone call from dropros!

Dave
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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #48 on: March 07, 2022, 12:00:33 AM »
Consider picking up a well made used dresser....you can get them dead cheap right now, and the drawer construction is fantastic.

You can use it as is, or make up a carcass.   

Dave
 
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #49 on: March 07, 2022, 01:44:28 PM »
Thanks Dave - really appreciate your comments. I hope you get your DRO soon. I am sort of torn on my install. I look at the use of the supplied universal brackets and find myself wishing I'd gone a more custom route as you are planning. However, the fact is everything is straight, true and solid. I cannot move anything about, it will take a catastrophe to shift the scales, so really it's perfectly good. But from an engineering perspective it's just not as elegant a solution as it could be.

But enough lamenting, when I start making parts I'll forget all that pretty quickly.

Also, great idea on the dresser, I had a quick look on local listings and there are LOADS, going for cheap, so I'll see what I turn up.

I have also discovered a flaw in my cross slide. The tapered gib for cross slide comes loose. What happens is that the rear screw that holds the gib  in place is barely contacting the rear of the gib. As the slide is moved well towards the center of the lathe, the gib is unsupported side to side (Z direction) on it's rear most area, and it slips off the support screw. Then, as you wind the cross slide back, the gib slips back a bit and now the cross slide is slightly loose. Then as you keep going towards maximum travel away from the center of the lathe the cross slide starts to bind up. It has been doing this for a while but it took me this long to figure out what was going on.

I am hoping to make a new rear screw, with a "reverse" taper on the underside of the head, and then grind a matching notch in the rear end of the gib, so that the screw actually captures the gib and pulls it in, and holds it. I think if I do this I can get the cross slide much better supported and true, and take some wiggle out of it that I did not know was there - another benefit of the DRO is being able to grab and try and move things, and see if the numbers change.

It's always something. It seems like I can spend forever trying to true up things and not make a single part. But if there are inherent inaccuracies in the machine tool, it's not going to help me make good parts and good engines.
« Last Edit: March 07, 2022, 02:53:46 PM by propforward »
Stuart

Forging ahead regardless.

Offline Admiral_dk

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #50 on: March 07, 2022, 06:43:14 PM »
Quote
But if there are inherent inaccuracies in the machine tool, it's not going to help me make good parts and good engines.

Amen to that !!!   Good that you found the reason and I really hope that the solution is as straight forward as you say  :cheers:

Function is the most important thing here !  We all prefer it to look good at the same time - but that is not always possible when converting an existing object ....

Personally I'm happy with my Z-axis scale, but my X-axis looks a lot worse than your Z. My first X setup looked very nice and worked precise, BUT .... I could not adjust the gibs  :-X  and I lost about 25% of Tailstock range  :censored:

I still think you're on the right track Stuart  :ThumbsUp:

Per

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #51 on: March 13, 2022, 06:47:02 PM »
Thanks Per! I have made some more progress. The DRO setup seems to be working well, so I spent some time looking into the cross slide.

These two pictures show the issue - this is the underside of the cross slide.



This gap between the gib and the slide at the far end is the problem. This does not allow enough "land" for the adjustment screw, and when you tighten the screw, it simply disappears into the gap and bends the gib outwards.



I had hoped I could machine an undercut in the adjustment screw to capture the gib, but there is not enough material at the screw head. Instead I'm going to buy a new gib from Grizzly - they are not expensive and hopefully it will fit better than this one.

In the meantime, I have managed to adjust the gib reasonably well so that I can keep using the lathe - well, I've used it for this long and made good parts so no need to stop, but I'll be happy to resolve this.

To help though, I have added a lock to the cross slide. I simply drilled and tapped a hole through the top of the cross slide, and added a counterbore on the inside as well as the outside.

Inside:



Outside:



I also made a brass plug, which locates in the counterbore on the inside, and is for the lock screw to bear against.



So obviously this works by having a cap head screw in the cross slide, which pushed the brass plug against the top of the saddle. This actually works a treat - way better than the original lock frankly, and there is no sign of any movement when turning with the screw locked. The location was chosen so as to allow the compound slide to completely rotate. The down side is that the lock requires a tool to engage. I think that the location is out of the way enough though to make a screw with a small handle so as to more easily lock it.

I will try it and see how that works out, but with my lathe back in operation it's time to start a new engine.

The backsplash is back on - I just needed to make a simple block to support the tailstock end, which is screwed to the top lip of the chip tray.

The bed pedestals have been silicone sealed to the chip tray, to prevent leakage of coolant when I'm using it, and now I just need a bit of a longer supply tube for the coolant feed.


Stuart

Forging ahead regardless.

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #52 on: March 13, 2022, 06:56:25 PM »
I am also replacing the drive belts with power twist belts from Fenner. Still waiting for the other one to arrive, it has so far been from Michigan to Pittsburgh, to Ohio, to Kansas City and then to Des Moines, Iowa. It has left Iowa, and I wonder where it will go next?  :Lol:

Stuart

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Offline Art K

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #53 on: March 14, 2022, 02:00:47 AM »
Stuart,
We had a similar problem with the lathe at work, an Enco 12 X 36 gear head lathe. Although the Enco has a notch in the back of the gib that matches the location of the rear adjustment screw. It was quite a surprise for me the first time it seized up and wouldn't crank out. After taking it apart I found the end had broken off and wasn't holding the gib in place. Nice project I'd like to put digital readouts on my lathe but haven't gotten around to it.
Art
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Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #54 on: March 15, 2022, 05:43:24 PM »
Still back ordered.    Scheduled to be in Port on the 30th
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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #55 on: March 15, 2022, 11:23:40 PM »
Art - thanks for the input - quite amazing how solidly they can bind up. I’ve ordered a new gib, hope to install it this weekend. If it’s better quality than this one I am hoping I can improve rigidity a bit.

Dave - really sorry to hear that. That’s frustrating!

My second twistlock arrived, so I will put that on at the weekend. I also tried running the motor only today, be removing the motor drive belt. The motor is actually very smooth. Perhaps a bit of vibration, but not much. Also there is noticeably less vibration anyway because of the more robust mounting.

The gear train is actuall where most noise comes from. I think my next round of investigation will focus on tool rigidity and and bearings, and gear adjustment on the lead / feedscrew drive train.

But over time - I’m happy with the progress and I’m committed to starting another engine on Saturday.
« Last Edit: March 16, 2022, 12:10:33 AM by propforward »
Stuart

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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #56 on: March 18, 2022, 02:01:49 PM »
Well I'm just going to vent, just because. I got my new gib yesterday, but it is supplied as a partially machined item which has to be finish machined and ground or hand scraped to fit. This irritates me, because the one that came in the machine was clearly machine ground, as was the dovetail, so this could easily be a finished and ground, ready to install part. Then again, they could just have screwed it up like they did the original. So I guess I have to try my hand at scraping.

This is what you get when you buy a cheap import machine. Not that I can't make good parts with it, but for anyone wondering, be prepared to tear into your imported machine tool if you want to get the best out of them.

We all knew that of course, I'm just a bit frustrated. Oh well. Carry on.
Stuart

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Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #57 on: March 26, 2022, 09:56:29 PM »
Enough lamentations. I have a plan to machine the new gib to size, which I will get to in due course. I figure even if I just machine the gib I can make a better one than is in the cross slide now, and improve matters.

But today I ran a few cutting trials just to see where things are. I played around turning a piece of old mild steel I had in the scrap box. I was interested in surface finish ans a measure of how much taper is in the machine - though I will conduct a more thorough test over a longer piece of larger diameter material soon. This is a quick look see while I had a few minutes.

This is the turned piece on the machine.



This is next to a ground center finder just for a comparison.







It's a shame the last pic is a bit out of focus.

Anyway, the as turned finish is certainly not as fine as a ground finish, nor did I expect it to be of course. However, I think it's pretty good. I kind of get hung up on surface finish because of what I see around, but for a small lightweight machine I think this is pretty decent. No taper measurable either, but this is only over a 1/2", so I'll test that properly. But I do feel my upgrades are yielding results, I don't think I ever achieved this level of finish before - and I can do it on some pretty heavy cuts. I took a .1" (diameter) cut without any real issue just to try it (at small diameters - 1/2" and less - machine starts working hard on these size cuts on bigger diameters). .15" was far too much though. That was terrible.  ;D

« Last Edit: March 28, 2022, 03:14:14 PM by propforward »
Stuart

Forging ahead regardless.

Offline steamer

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #58 on: March 26, 2022, 10:34:13 PM »
Stuart...let me know how you make out fitting a gib....send me a DM....

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #59 on: March 26, 2022, 10:48:20 PM »
Will do. Another journey that I'm heading into blind. Hey, the worst that can happen is it doesn't work and I still have what I already have.

Oh - and my modified chip tray works a treat. No more coolant on the floor, and the return to the reservoir is faster than before. Brilliant.
« Last Edit: March 26, 2022, 10:52:33 PM by propforward »
Stuart

Forging ahead regardless.

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #60 on: April 10, 2022, 11:49:50 PM »
I now have a plan for finishing up the gib that I bought from Grizzly. I've been doing a bit of research and looking at what others have done. Based on some test cuts on cast iron, I think I can get a good part by milling the gib to size. After that I can try my hand at scraping if I really need to, but I think I can at least get a better part than is in the cross slide now.

So to do it, I am going to glue the gib to a flat plate using toughened superglue. I'm not a fan of using glue to fixture things, but at the end of the day if it holds the part then so be it.

So I started off by skimming a steel bar. This bar is yet another piece of nice steel that was literally being thrown away. I'd like to go on about what a disgrace that is, but it ended up being thrown away in the back of my truck with me getting it for free, so WIN!

Got a few piccies here - nothing exciting really. I tried skimming it dry. Then I tried using a bit of cutting oil to improve matters.




It worked better in the vice.





This worked well enough, but I decided that since I have flood coolant available, I would use that.





This worked great, but at the high rpm's I was trying the coolant went EVERYWHERE!  :lolb: Benefit of a separate shoppe I suppose. I had to rush around and get some makeshift splash guards in place.

However, net result is a nice flat bar - like .0005" flat, so I think this will be a good start for what I am going to try next.



The idea is to mount the old gib next to the new gib, so I can get the bar angled properly, and touch off on both new and old gibs and see how much to machine back.

That part is still to come.

Stuart

Forging ahead regardless.

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #61 on: April 23, 2022, 04:35:38 PM »
Well now. This is not for the feint of heart................. >:D

What I have done here is not how you are SUPPOSED to make a gib, but I decided that I surely cannot make a worse gib than was supplied with the lathe in the first place, ergo any improvement I make must surely be an improvement, even if it is not as good as it should be.

So - I got some of the toughest superglue I could find, and I glued the new gib (rear) and the old gib (front) on my flattened steel bar.



I used the old gib as a reference to angle the bar until both gibs were presented at the right angle. Note - I only used the "good" end of the old gib, as the thinner end is not flat or true in any way shape or form.

I then installed a brand new carbide end mill, run at the highest rpm I could, and proceeded to skim off the .060" inches of extra material on the new gib. I ascertained that dimension by using a test indicator and touching off on both gibs in multiple spots. I actually measured .063" but decided to play it safe, since I have extra length on the new gib.





This worked like a charm. Now I know that gibs are supposed to be ground and then hand scraped, but I'm well happy with the achieved finish.



So I test fit it - and it was looking good. I marked it front and back, and cut off the excess using a bandsaw - but playing it safe (ie cut it long) and did some more test fits. After trimming off a little more, I set up my little tool grinding post to steady the gib and ground a notch for the front adjusting screw, and reinstalled the gib.

Here is the handwheel end - as you can see there is still room to trim a little more, but no need, this is fine.



Net result..................

It absolutely works! I now have an even drag of the cross slide over its whole range, and when I grab it and try and move it there is no change in reading on the DRO, whereas with the original gib I could move the DRO several thousands quite easily, and the cross slide always felt loose and slack (it was).

So - I don't doubt that the gib is not properly seated in normal precision lathe terms, but it's a heck of a lot better than it was. I'm very excited, and now I'm going to turn some test parts and see how it performs.  :ThumbsUp: :ThumbsUp: :ThumbsUp:
« Last Edit: April 23, 2022, 06:37:10 PM by propforward »
Stuart

Forging ahead regardless.

Offline Kim

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #62 on: April 23, 2022, 04:49:25 PM »
Looks great to me, Stuart!  And proper lathe etiquette or not, the results speak for themselves!  Congrats on successfully completing something new and different!

Kim

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #63 on: April 23, 2022, 04:59:46 PM »
Thanks Kim! I just made an attempt at taking .0005" off a piece of aluminum and slap me sideways if it didn't work. Never been able to reliably do that before. Noticeable improvement in surface finish as well, which I ascribe to reduced chatter.

What a great day - I'm over the moon with this.
Stuart

Forging ahead regardless.

Offline crueby

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #64 on: April 23, 2022, 06:34:29 PM »
 :whoohoo:   So much more fun when the tools do what they should!   :ThumbsUp:

Offline Admiral_dk

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #65 on: April 23, 2022, 10:04:52 PM »
Quote
:whoohoo:   So much more fun when the tools do what they should!   :ThumbsUp:

Double Amen to that statement  :praise2:    :cheers:

Per

Offline propforward

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Re: Grizzly G9249 Lathe Improvements and DRO install
« Reply #66 on: April 23, 2022, 10:44:27 PM »
Heck yes! It’s a game changer. A lot of frustration with this lathe went away today. It took me a silly amount of time to figure out what was wrong, but I got there eventually.
Stuart

Forging ahead regardless.

 

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