A unique automatic radial infeed ball turner experiment with micrometer adjustment.

[Mook]

This was an experiment to see if I could include all the features I would like in a single compact unit. Definitely not a commercial soluiton just a bit of investigation to see if I could get new features all working together.

[Ralphxyz]

Now we need details on how you built it! How is the depth adjustment done. Lots of design questions.

[Mook]

Now we need details on how you built it! How is the depth adjustment done. Lots of design questions.

Thanks for the request.

This is the very first prototype which works, but can be improved. I wouldn't want anyone to copy a product that is not ready, so I won't release details for people to make and then blame me that it is not ideal.
To answer your specific question.
The radius stop is set by the micrometer, from memory, I believe the micrometer reading it is the desired radius less ten. Once this is set the stop for the foot diameter is then set. The tool is then retracted to clear the blank and the process starts until the clutch slips. You can continue to cut spring passes to improve the finish.

Here is a link to some images taken during manufacture.
https://drive.google.com/drive/folde...kG?usp=sharing

[Jon]

Congratulations Mook - your Radial Infeed Ball Turner is the Homemade Tool of the Month for March 2026!

Another tough month to win, but this is the most intriguing ball turner design we have seen. And the followup post with plans suggests that we may be seeing more similar designs on this forum in the future.

Some more good builds from March:

Slitting Saw by Great Ideas Catalogue
Tool Post Stop by Occasional machinist
T2 Tool Holder by thehomeengineer
Rotary Broach by bbutcher85
Pritchel Plate by Philip Davies
Can Venting Machine by desbromilow
T-Nuts by Improvised DIY
12V Battery Monitor by rgsparber
Automotive Pipe Bending Tool by Classic Bodywork
CNC Fourth Axis by bbutcher85
Speed Square by Improvised DIY
Radius Turning Tool by jerek
Electric Cargo Vehicle by tado creation
Knife by Wood-N-Metal Workshop
Telescoping Electric Lift System by Kwandotechnic
Parallel Clamp by Deez Workshop
T-Joint by Improvised DIY
Off-Center Chuck Modification by The Hobby Machinist NZ
Sheetmetal Cutter by mariost
Drawbar Hammer by Deez Workshop
Convex Cutting Jig by Make Things

Mook - You'll be receiving a $250 cash prize, in your choice of Amazon, PayPal, or bitcoin. Please PM me your current email address and prize choice and I'll get it sent over right away.

More importantly, you're our first winner of our 3-Time Homemade Tool of the Month Award! Your last two wins:

Work Supports
Ratchet Tap Wrench


And, you'll now notice the bronze four-column award in the awards showcase in your postbit, visible beneath your username:





Nice work

[Mook]

Here is another video showing a 40mm Aluminium ball being turned with some more information.