Author Topic: Workshop Log  (Read 13941 times)

Online Kim

  • Global Moderator
  • Full Member
  • *****
  • Posts: 4159
  • Portland, Oregon, USA
Re: Workshop Log
« Reply #150 on: October 09, 2020, 06:18:26 AM »
Very nice work on your DRO installation, Stuart!

It always seems like these 'little projects' take a long time and a lot of effort.  But I think you'll be super pleased with it when its done.

Kim

Offline gary.a.ayres

  • Full Member
  • ****
  • Posts: 865
  • British Isles & sometimes France
Re: Workshop Log
« Reply #151 on: October 09, 2020, 09:24:48 AM »
Yay!

Congratulations on the DRO Stuart!

You'll never want to be without one again...   :cartwheel:

Your shop is looking great, btw.

gary

Online propforward

  • Full Member
  • ****
  • Posts: 713
  • MN, USA
Re: Workshop Log
« Reply #152 on: October 09, 2020, 01:22:23 PM »
Thanks Fellas. Kim, these upgrades certainly do take a lot of work - but very satisfying in their own way. I'll be very interested to tidy up all the cable routing and then do some test measurements on gauge blocks and verify accuracy and repeatability. I sense a spreadsheet coming on!

Thanks for your comment on my shoppe Gary - I've been working to complete motorcycle projects and get rid of them over the last couple of years. So that's why not very much progress on model engines. It's a case of sell off now unwanted projects, and then the money is used for tools and upgrades. I'm getting to a point where my shop is a lot more organized with decent space, and more spare time will be available for engines. It's somewhat a path to a retirement hobby, although retirement is a ways out.

If this DRO is as good as I hope, then after the next motorcycle sale I may well add one to the lathe. The lathe needs a bench upgrade as well.

A note about DRO PRO's - I've been very happy with their service. Although my kit was missing  couple of brackets, I wrote to them and they had those brackets to me in two days. At the same time, I asked if I could buy a couple of extra brackets, as after some dry fit I could see a neater mounting solution than just what was normally supplied would allow. Well, they just shipped those brackets with the missing ones, no questions asked. Little things like that matter.

Anyway, should have X,Y and U fully installed on saturday, then I need to plot and scheme a bit more on the Z axis, although I have a basic plan in mind.
Stuart

Offline gary.a.ayres

  • Full Member
  • ****
  • Posts: 865
  • British Isles & sometimes France
Re: Workshop Log
« Reply #153 on: October 09, 2020, 11:24:32 PM »
Stuart -  a DRO on a lathe would be wonderful. I saw one on an immaculate beige-painted Myford Super 7 on show at a ME exhibition in Bristol a few years back. Stunning!

Online propforward

  • Full Member
  • ****
  • Posts: 713
  • MN, USA
Re: Workshop Log
« Reply #154 on: October 10, 2020, 05:26:04 PM »
Yes I think that would be a fantastic addition. I aim to see how I get on with this set up, and maybe next year after I sell a couple more bikes on, I'll invest in a lathe set up. That will have to wait though.

Meanwhile - I finished up the X, Y and column DRO installs.

I've been using a DTI to get the scales as parallel to the relevant axis as possible. For the most part this was not difficult. The Y took me a few goes. Here is the column getting checked:



Then using the shim to set the read gap:



After that, it was a matter of routing the cables so that they don't tangle with anything. The cables are very long, so that they will work in any installation. No big deal, I routed them where I wanted them, then looped them up and tied them in place on the rear of the column out of the way. Can't even see them when working the mill.

Loop for the column:



At maximum lower travel the cable loop stays nicely clear of everything. The metal clips and screws come with the kit - just a matter of drilling and tapping a hole where you want it.





And the back of the machine:



Cable loops for X and Y:



You may think that I have lost some table travel in the Y direction, but not really. The table is past the center of the spindle before the screws holding the sensor bracket hit the column, and the lower concertina actually compresses and stops the table just ahead of the screws hitting, so although technically I could take the concertina guard off and get another inch of travel - in reality I'm never going to need it. Haven't yet in the 7 years I've owned the mill.

I may put a thin cover over the top of the X scale and read head, but it's not critical.

Just the quill axis to figure out now! I need to do some scheming. But I'm ready to use X and Y, which is a great start. I have already figured out some play in the handwheel drives that were likely the result of some position inaccuracy I was seeing. I could compensate now I know about it, but this is better.
Stuart

Offline gary.a.ayres

  • Full Member
  • ****
  • Posts: 865
  • British Isles & sometimes France
Re: Workshop Log
« Reply #155 on: October 11, 2020, 11:02:45 AM »
Looking great, Stuart. What a clean shop too! The mill is immaculate.

Here's how I did mine:



Nothing much to teach you - I'm sure you know more about this than I do, just for interest (and an example of a shop that is neither clean nor tidy most of the time). However one thing I was quite pleased with was my idea for guards to protect the scales fro swarf, made from square section rainwater pipe (seen in the second video).

On DRO's on lathes: absolutely! In fact the Myford ML10 that I have in France has the scales on it already from the previous owner. All it needs is the display, which is on my 'to do' list. Unfortunately, though, that seems to be the machine that has suffered the most water damage. I'm daring to hope it will be ok though...

Online propforward

  • Full Member
  • ****
  • Posts: 713
  • MN, USA
Re: Workshop Log
« Reply #156 on: October 11, 2020, 08:27:26 PM »
Thanks Gary.

Great videos! Some good info in there and food for thought. I know you'll be able to recover your Myford. It's heartbreaking for sure, but stay positive.

I've been enjoying my mill the last day or so. Mounting the quill DRO requires a bit more custom effort than the other axes. My original plan was to fix the scale, and make a bracket to hold the read head to the quill somehow.

I've decided to go the sliding scale approach instead though. I mocked up something to get my head around it. Bit of a crude model here:



The idea is to make a bracket set up from aluminium bar that holds the scale firmly as it passes under the read head. This will be important, as the scale will mount to a flat bar that is only attachd one end, but attaches to a clamp firmly secured to the quill.

Anyway, made a couple of bits from stock I had laying around





Nothing fancy at all, but these parts were very quick to knock out, and more accurate than I normally achieve.



0.0015 over length! Bah! (Well, 0.001 to 0.002 over length, instrument uncertainty being what it is.  :Lol: I'll take it).

It has been interesting to discover how much play the machine dials have before the table actually moves, and also how far the table moves when locking into position. For sure a 1/2 thou every time locked, but without compensating during tightening the clamps, can jump 1 or 2 thou - especially when unlocking. All told it's easy to see where 5 to 10 thou of variation can creep in when you can't see it.

Anyhoo, got some more material on the way to get this finished up.

In the meantime I did add a cover to the X axis, since that scale and read head were getting covered in swarf. The DRO kits come with a length of extrusion for each scale, a simple right angle lipped channel. Cut to length, and drill a clearance hole each end to mount to the scale, in tapped holes provided for the purpose. Neat and simple, and still sub flush to the table top - and even with this I still don't lose any table travel.



Underside showing how the extrusion covers theread head and scale. I need to put a notch somewhere to get better access to the table oiler. Or just pop the cover off once in a while.



I'm looking forward to getting the quill done, because I have figured out how to move forward on my steam engine base casting, having watched a machinist at work establish a position on a very complex part by using pin gauges. But I need to accurately machine to depth using the quill, so might as well finish up this install first.

Also, need to conduct a small capability study and understand how well the DRO system is measuring - but based on my little exercise today they are doing a better job than going off the hand dials.

 :ThumbsUp:
« Last Edit: October 11, 2020, 08:32:17 PM by propforward »
Stuart

Offline gary.a.ayres

  • Full Member
  • ****
  • Posts: 865
  • British Isles & sometimes France
Re: Workshop Log
« Reply #157 on: October 11, 2020, 10:06:58 PM »
Thank you Stuart. The Myford and othermachines are now under plastic.   :ThumbsUp:

I reckon there are as many ways to install a DRO as there are DRO installations!

Very nice job.

I see you have discovered the joys of table lock movement.   :)

I was fortunate in that my mill came with a small DRO on the z axis. Not as good as the real deal, but good enough to make it not worthwhile to mount a scale on the quill...

Enjoying this thread!

 :popcorn:

Offline Sleddog

  • Full Member
  • ****
  • Posts: 40
  • South East South Dakota, USA
Re: Workshop Log
« Reply #158 on: Today at 01:34:23 PM »
Prop, I’ve got a DRO Pro mounted on my 755 also. You’re going to enjoy not counting revolutions!
BTW, it’s ‘meringue on the PIE’ not cherry on the cake🤦‍♂️

Cheers