Grizzly G9249 Lathe Improvements and DRO install

[Kim]

Boy, you're really doing this lathe project up right!  Nice welding on your chip/coolant tray too, I might add!

Kim

[propforward]

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!

[steamer]

Still watching Stuart!    I like the approach on the Z axis.     makes sense to me!!!

Dave

[propforward]

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.

 

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.

 

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

[Kim]

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.

 

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

[steamer]

Nope!!! Publish warts and all!!!  That way I get to make NEW mistakes!!!!

Dave

[Hugh Currin]

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.

[propforward]

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.

[propforward]

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.

[ShopShoe]

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

[gary.a.ayres]

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

[propforward]

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.   

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. 

Needed a break, so I thought I'd write this intermediate blurb.

[propforward]

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.

[gary.a.ayres]

It's a great feeling to see that display doing its counting thing for the first time, is it not? 

[steamer]

Looks great Stuart!     Did you end up with a center support?  or just the ends?

Dave