Holding The Wide End

[rgsparber]

Picture trying to machine a rivet's narrow end in a lathe. How would you do it? The jaws cannot solidly grab the rounded end. Even if they did, the rest of the rivet's body would be unsupported. With a small side force, the rivet tips off center.

Here is how I deal with turning the small end of a rivet-shaped object.

http://rick.sparber.org/Holding%20The%20Wide%20End.pdf


Your comments are welcome. All of us are smarter than any one of us.

Thanks,

Rick

[mklotz]

Machining miniature parts for models often requires holding things with odd-shaped protrusions so I have a whole box of these homemade split collets, many of them with recesses carved into them to accommodate the protrusions.

It's worth pointing out that by threading the hole before slitting the collet, one can securely hold threaded parts with no fear of damaging the threads. Dogpointing tiny screws is a typical example.

[rgsparber]

I hold threaded stock in hex nuts that are cut axially. They are barely long enough to give good alignment but do work ok. You can look in Home Shop Machinist Vol. 35 No. 6 Nov-Dec 2016 for a 3 jaw version that is much more stable.

Rick

[mudnducs]

"....In order to insure that I would never use this collet again, I saved it to my small fixture drawer...."


I love it. <g>

[rgsparber]

Glad you liked that. My kids just give me an "eye roll..."

Rick

[madokie]

i make my "collets" out of scrap steel, i usually dont have to pry or press to remove part,,i also have 3 sizes of drill chucks handy, so i can put part in it then put drill chuck in lathe chuck and machine away.

[garage nut]

Great Idea...Thanks

I have to try and repair my friend's HD front brake master cylinder push rod the week end.



Was wanting to turn the damaged part down and tread the shaft and screw the replacement part on. Easier to repair in the future.

As you know there is a ball shape in the cylinder. Any ideas as the front is nor thicker than the shaft??

[DIYer]

Thanks Rick! We've added your Rivet Holding Fixture to our Lathe Accessories category, as well as to your builder page: Rick's Homemade Tools. Your receipt:

Rivet Holding Fixture by Rick Sparber

tags: rivet, lathe, collet