True Adjustable Er-32 Collets

rdean

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Let me start by giving credit to davidpbest for giving me the inspiration to start this project.
See his thread here http://www.hobby-machinist.com/thre...camlock-collet-chuck-build.61759/#post-509211

Unlike David I was too cheap to purchase a D1-4 mounting plate and had originally thought about making one until I remembered the 10" mounting plate that came with my lathe. I had never used it in the year and a half since I bought the lathe so why not use it instead of buying a backing plate. If I need the backing plate for a job I can easily remove the adapter and since the adapter is adjustable putting it back on true would not be an issue.
I recently bought a set of ER-32 collets in metric sized from 2mm to 20mm in 1mm increments so that's what I will use.

I started by drilling and taping three holes in the face plate.
GEDC3266s.jpg

I cut a 2" long piece off a 5" diameter piece of aluminum I had. Trued up both ends and mounted in the mill.
GEDC3268s.jpg

Found the center and using the bolt circle program drilled 3 holes to match the mounting plate. These holes were then counter bored to 0.750 diameter and to a depth of 1 1/2".

GEDC3270s.jpg

Everything lined up well and a success for today.
More tomorrow

Thanks for looking
Ray
 
Looks great and a good idea for multi use of your tooling. A bit of a heads up, though. On my 13x40 Asian lathe, the faceplate is limited to 1255 rpm. Yours may be different. Much work in collets is small diameter and you often need all the spindle speed you have available for a good finish and quick cycle time. Sometimes face plates are also not in good enough balance at high RPM for the lathe to run smoothly. Test it and see.
 
Looks great Ray. Very resourceful.
 
More progress
Mounted the face plate on the lathe and cut a 3/4" deep by 4" diameter recess for the collet plate to sit in.
I originally wanted 4 bolts to hold down the mounting plate as you can see there are only 3. No matter how I aligned the 4 bolt pattern there was not get enough room for good threads at all the holes. I still wanted 4 adjusting screws but that put one of the screws in 1/4" thick material in the main mounting screw relief hole. I don't think this will be a problem as there won't be much stress on the screws after the plate is tightened down.

GEDC3275s.jpg

I cut another piece of 5" diameter aluminum 1" thick. I used a 4X6 HF band saw and I knew I would have to turn the material several times in order to cut all the way through. Other times when I have done this the cut was not nice and the thickness varied by about 1/4" when done. I needed the plate to end up 3/4" thick after machining so I cut it an 1" thick. Wouldn't you know it the cut ended up almost perfect at 1" all around. Now I had to remove 1/4" off the thickness.
Lots of chips.

GEDC3278s.jpg

Drilled the center hole and the three mounting holes with the counter bores.
I was almost done milling the plate when I realized my hold down clamps were not tight enough. The plate shifted over a couple of inches and now I lost my X and Y coordinates. Was able to finish by using a center punch in the arbor of the mill and then Z down into each hole to find the center.

This is the chunk of steel that hopefully will become my collet holder.
GEDC3281s.jpg

We will see how that works out.

Ray
 
Didn't get much done today but did get the collet holder pressed into the base.
Was definitely a hard press but ended up very true.
GEDC3283s.jpg

Mounted everything on the lathe, centered the adjustable plate and trued up the steel slug.

GEDC3284s.jpg

Very happy so far and no problems today.
Thanks for looking

Ray
 
Bored a 7/8" hole all the way through the soon to be collet holder. Cut a 8 degree taper on the inside and 1.5mm threads on the outside.

GEDC3286s.jpg

GEDC3289s.jpg

All done except for cleaning up.
GEDC3291s.jpg

The project turned out quite well even after having several screw ups and plan changes.
If I had it to do over again I would use a 4 bolt pattern for all mounts.
I can move the center plate 0.050 in all directions but for now it is true.

Thank you for the likes and comments.

Ray
 
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