ER25 Collets set with holder, nut and M33 lathe pickup, and quick change handle.

This model(set) is for those who 

• want to connect, firmly but detachable, something round between 1 and 16 mm diameter to their print. A collet then is a good option. 

• have an ER25 collar holder and nut system but in their collet collection miss exactly that one size they now need. This set aims to provide compatible collets in the full range for ER25: so 1-16 mm. They may not be as accurate as the steel originals and the holding power is not as good, but one of these may just do the job. 

• You are a woodturner, you need to mount that 13 mm diameter blank, and the jaws you have do not provide grip for this size. 

• ADDED 02 October 2025: want to use their M25 collet holder to chuck whatever profile. Use the 1 mm collet model and in your slicer subtract the shape you want.

• ADDED 27 December 2025:  Want to make their own quick change handles for tools.

• ADDED 27 December 2025:  Want to make collets for holding items with a square 10x10 mm pickup, like these. 

The set comes with models for:

• Collets for clamping diameter of 1 to 16 mm. 

• A generic holder. The holder has a block base which you can clamp into a vise or merge with your own models.

• A nut to tighten the collet. The nut has a hexagon outside. 

• As a bonus there is a model of a holder with an adapter that fits on the M33 pickup of a woodturning lathe.  This allows you to ‘chuck’ wood elements that are too small to clamp them in your chuck. 

• ADDED 27 December 2025:  A mount on 28 mm thin walled heating pipe as available in hardware shops, do make quick change handles.

Notes:   

• ADDED 27 December 2025:  The quick change handle is a set of 4 elements, two of which are to be bonded onto the pipe in the correct order. The outside part, which the would be pulled off the pipe when the collet is squeezed, first and then the internal part which would be pushed into the pipe.  See detailed instructions below.

• ADDED 02 October 2025: be sure to mount the collets correctly, and in exactly the same way you fit steel collets in a steel holder : with a ‘tipping’ motion hook up the collet in the nut so the rim inside the nut snaps into the groove around the collet. Dismounting in reverse order.  

• Plastic collets are nowhere near a full replacement for the full metal originals. They do not give the same accuracy and holding power. They are at best a ‘make do’ in some cases and less than useless most of the time. 

• Obviously printed plastic cannot even stand in the shadow of steel when it comes to strength. To add worse to bad, the coefficient of friction of plastics iin less than those of steel so you would need to apply higher pressure for the same holding capacity.

• I do not have access to metal collets or holders to verify the fit. I tried to follow published dimensions, though. Fit with 'official  holder and nut is an expectation, not substantiated by evidence or tests. 

• I had a question about using steel collets in the printed holder. I recommended against this because the plastic holder and nut will not be able to provide the forces required to deform a steel collet.  

• I mimed the dimensions of the steel system as a starting point. For plastics the dimensions, taper angles may not be optimal. This is a point for investigation and improvement.  

• I also did not try to add ribs and other grip enhancement features that are easy to print but would be difficult to machine in steel.

• I made my prints with Fiberlogy ASA on an MK4 printer in a home made enclosure. Settings for all parts were as in the enclosed .3mf file for the nut. In that file note the support enforcer that raises to just below the pull-out ridge. This support was needed because otherwise the pull-out ridge did not print correctly. 

• The collets are best printed with the steeper cone down, so flipped relative to the arrangement they are in the .stl file. Use a brim and supports.

• The .stl file holds models of all collets 1-16 mm. In PrusaSlicer use ‘Split into Objects’ and you will have 16 objects. The number represents the diameter. The collets are arranged in 4 rows: 1-4 mm, 5-8 mm, 9-12 mm and 13-16 mm. There are dimple on the nut side edge. The number of dimples represents the diameter in mm. The dimples may not show up on the print. I found them convenient for identification during slicing. 

• Best at first just print a selection of the collets. In PrusaSlicer just toggle the visibility for the ones you do not want to print. They will then be ignored during the slicing. I just printed the 6, 8, 12 and 16 mm versions and left the rest for whenever I need them.  

• I used ASA for this because I thought that maybe I need to smoothen the surface with acetone. I did found this wasn't necessary.  

Special instructions for the assembly of the quick change handle: 

1. Make sure your printer is well calibrated and that shrinkage is accounted for. I use 2% shrinkage in X and in Y direction for Prusa PC-Blend. 

2. Make sure the pipe end where you want to fit the ER25 take-up is not deformed and free of burrs are removed.

3. Have CA glue and a small wooden hammer ready. 

4. Check the external part (with the external thread) fits smoothly on the outside of the pipe, sliding and rotatable, with the rim resting on the edge of the pipe. Also verify that the internal part (with the internal taper) would go into the pipe with the help of light tapping with a wooden hammer.  

5. Carefully clean and de-grease the inside and the outside, roughen up with fine sandpaper, and clean and de-grease again.    

6. Bond the external part on the outside of the pipe.  Use no pressure to  push in in place,, as that could deform the thread. Make sure the parts it sits square on the pipe. 

7. With CA glue mount the internal part. 

8. Allow ample time to dry before tightening. 

Credits:

• I used parts of Gilles Bouissac's thread library for making the threaded parts.