sherline mill dti holder for tramming

[ttrikalin]

It's been several months since I did any machining... we moved in the meanwhile and it took me too long to deploy the tools again...

before going back to micromachine the 1/4 scale of the tiny, I made a better bugger to hold the dial test indicator I use to tram the mill...

here's the old thread - if you're bored...

http://www.homemodelenginemachinist.com/index.php?topic=6819.0

I was using the 4 jaw chuck on the spindle to hold my DTI so that it runs on a bearing race (diameter ~3").

D.C. Clark showed a picture with a much better setup -- he was using a bar held in a collet... following his lead, I made the following gizmo... The big part is a Morse 1 taper that fits the sherline spindle... the horizontal bar is 5/16 steel rod, unfinished : ... and the part on the left has set screws to fix its position and to hold the dti stem...

here's the dti

nothing more to it really... felt like posting something...

tom in MA

 

[Russel]

I know this is an old thread, but...

This is the DTI holder that I made for tramming the vice, or whatever to the mill bed. I currently use a collet to hold the test indicator when I want to tram the mill, but I'm planning to make a small version of Bogstandard's dual dial indicator tramming tool. When I do, I'll post it here.

Russ

 

[Russel]

I know that this thread is titled Sherline Mill DTI holder, but I figure this is a good place to add a dial indicator holder for centering a Sherline independant 4 jaw lathe chuck. Hopefully, someone will find this information useful. The dial indicator is from LittleMachineShop at $15.00 US, so the overall cost is minimal.

 

[dalem9]

Russel That is nice I like it .Dale

 

[ttrikalin]

nice, I copied you

take care
tom

 

[Russel]

The dial indicators that I orders from LittleMachineShop.com arrived, and this is my attempt at a dual indicator mill tram tool.

The first thing that I did was to use my Starret DTI to measure the error in the mill table. Moving the table along the X axis from .850” to 9” (the full travel of the X axis) I measured -.0005” at .one end of the table and 0.000” at the other end. Not too bad, about half a thousandth error from one end to the other. Next, I measured the error from the front to the back of the mill table along the Y axis. I measured 0.0000” at the front and .0007” (reading between the .0005” lines) for an error of a little over a half thousandth.

Now that I know the error in the table using a DTI fixed to the Z axis, it's time to calibrate the DDTI (Dual Dial Test Indicator) tram tool. I do this by moving the table out so that I can place only one DTI on the table and zero it, then rotate the DDTI 180 degrees without moving anything else and zeroing the other DTI on the same spot.

Finally, the test results! With the tram tool aligned with the X axis (note: table error about .0005” over 8”) I register just about spot on. Not too bad. It took me about an hour to tram this before I made this tool. Turning the tram tool 90 degrees so that it is aligned with the Y axis (note: table error about .0007”) I measured about .0003” error. Still not too bad, but now I can correct this in much less time.

Anyway, this is my attempt to make a tram tool similar to Bogstandard's but for my little Sherline mill. I've included some plans, although I'm no drafting expert, so if you have questions, or suggestions, please feel free to comment.

 

[ttrikalin]

nice job.
I will admit that I tram to within .0005" over 3 inches and let it there... takes me enough time already... But on the other hand -- if I could easily tram better than that -- as you can, I would definitely do it...

take care,

tom in MA