Turning Small Parts

T

tmerkl

Joined
Jan 8, 2007
Messages
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Does anyone have some advice they could share about turning small parts like custom thumb studs and pivot collars? Is this possible to do starting with rod stock, chucked in the collet of my mill? I do not have a lathe, so any tips on doing this in a mill would be especially helpful. I know a lathe would be ideal for this, and i can probably get access to one, so throw those tips my way too! Especially interested in how you guys separate the parts and don’t lose them by having them fly across the shop, ha!
 
Turning works fine as long as you get a sharp tool on center. Drilling is going to require accurate zeroes and the drill to be square. A collet holder in the vice holding the drill bit would be very helpful. Do you have a DRO or a decent indicator? For parting off you will need to run slow or something like a 1/4" shank cut off wheel holder held in the vice might work with the part spinning fast. As far as catching the part maybe figure out a way to get a Dixie cup or similar around the cut off holder.
 
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A mill can be used like you say without a lot of trouble. It's not terribly convenient but it's not hard. A DRO is very helpful because you can set multiple tools for multiple operations up on your table and set 0,0 work offsets for each of them. A collet holder on the table would be nice but you can hold a drill in a V-groove in a vise as well.

There really isn't anything you can't do within the scope/size limitations presented by chucking your stock in R8 collets, outside of single point threading. You can tap, turn diameters, part off, turn with form tools, drill, etc etc.

You can even thread the OD of a small part using a die holder and the quill.
 
Stick some round stock in your collet, mount a cutter in your vise, and go to town. Setup may take a little time, but shouldn't be terrible. A DRO will simplify things greatly if you have one.

Like Kuraki said, a collet block would be a nice addition to hold your parts in the vice for drilling and tapping and such.
 
I chuck up lathe tools in my vise and Turn stuff down no problem...
 
Thanks for the replies guys. I think it's time for me to watch some youtube about finding center and what kind of cutters i need to get. I do have DRO on the mill for the xy axis by the way.
 
For thumbstuds and pivot collars all you should need are some HSS lathe bit blanks. 1/4" or there about. Grind them into shape. Decide whether you want the tool on the right or left of the spindle (or both maybe, for some 2nd operation work) because the orientation of the tool will effect whether you need to run the spindle CW or CCW and have the cutting edge visible.

But you just grind those tool blanks to what you want. Finding center is easy. Just edge find your tool face.

I wouldn't even buy a parting tool for what you're doing, I would just grind one of the tool blanks into a miniature parting/grooving tool. For the diameters you're going to be working with it will work great.

Watch some videos on how to grind turning tools. Here's an example. A simple domed thumbstud with some grooves. 3 form tools and a straight turning tool (not shown). Will do all the curves, grooves, and part the thing off using the groove tool.

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Yeah personally, parting, is one of the things I'd recommend avoiding when using the lathe as a mill. It's a lot trickier, and you're more likely to lose parts.


Use a piece of folded leather, in a vise, clamp the good end of your part in it, and just cut the piece off by hand. That way, the bar goes flying, not the part. Otherwise, cut 95 percent through, and then just bend/break the part off and clean up.

Doing cleanup of small round parts does encourage coming up with some kind of little holders though.
 
If your parts are magnetic, just hold it next to the part before it flies off... ;)

As for finding center, just use an edge finder with a .200 end, and when it touches your cutting tool, move your table another .100 into the tool. Just don't turn your edge finder down...
 
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