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Magnum164
08-17-2010, 11:01 PM
OK,

Now that I have my lathe tuned and started turning my first projects. I realized that after I turned my first designed part my lathe dog will not clamp a 3/8 dia part:eek:

Soooo.. What can I use to turn small parts between centers? One side is 3/8 inch about 2 inches long and the other end will be about 1/2 for may 1 inch long.

Is there alternatives to a lathe dog?

Mcgyver
08-17-2010, 11:05 PM
they're easily made in those small sizes, drill a hole a little over 3/8, put a set screw in the side, with the aid of a torch bend over the leg....or bore a piece a little over 3/8, set screw, and well the leg on

dp
08-17-2010, 11:06 PM
They're very easy to make:

http://homepage3.nifty.com/amigos/carrier/carrier-e.htm

squirrel
08-17-2010, 11:08 PM
Here is one I made for our OD grinder, a threaded screw goes in the bottom.http://www.contractmachining.us/lathe%20dog.jpg

Magnum164
08-17-2010, 11:13 PM
Thanks for the info.

@dp

I was actually just looking at that site. That is what I had started to make.

I guess what I was hoping for as well was to be able to machine as close to the ends as possible. But for that small of dia I could probably get away with a 1/3 thick bar.

Magnum164
08-17-2010, 11:49 PM
Ahh,,,

Found a solution so I could at least start finishing my part tonight.. Make the lathe dog later.

But I found a round piece that was cutoff from another project and just wedged it in the lathe dog with the other part...

Which made me think that a small insert inside a normal lathe dog can be used to capture smaller parts. One dog for everything:)

Paul Alciatore
08-18-2010, 02:33 AM
Lathe dog for a 3/8" diameter? I would get a 1/2" shaft collar with a set screw and be half way there. Drill opposite the set screw and tap for a screw (#10 perhaps). LockTite a screw in, cut off the head, and bend it 90 degrees and you are done.

If you want to be a pureist, make the collar from 1" OD stock.

Arthur.Marks
08-18-2010, 10:51 AM
;) http://www.sherlinedirect.com/index.cfm?fuseaction=product.display&product_id=487

Davidhcnc
08-18-2010, 11:33 AM
..they are called lathe pups:rolleyes:

Magnum164
08-18-2010, 01:14 PM
Thanks for the feedback, I was hoping to get more suggestions on my question and that is:

are there alternatives? I have seen some face drivers which I like as it would allow me to turn closer to the end of my part. If I decided to CNC my lathe it seems that would be a lot quicker setup as well. Frank Ford has a nice one, but I don't have the link to it on this computer. It would be hard to scale that down to the smaller parts though I am sure.

Richard Wilson
08-18-2010, 01:53 PM
Do you actually need to turn these parts between centres? I usually put a piece of over length over size bar in the 3 jaw, centre one end for tailstock support, turn the part and part off. Makes slender shafts slightly stiffer because holding one end in the 3 jaw with tailstock support at the other is the equivalent of a beam built in at one end and simply supported at the other, whereas between centres is the equivalent of a beam simply supported at both ends. Usually the only time I have to use the between centres method is on crankshafts.

richard

Magnum164
08-18-2010, 06:18 PM
Do you actually need to turn these parts between centres? I usually put a piece of over length over size bar in the 3 jaw, centre one end for tailstock support, turn the part and part off. Makes slender shafts slightly stiffer because holding one end in the 3 jaw with tailstock support at the other is the equivalent of a beam built in at one end and simply supported at the other, whereas between centres is the equivalent of a beam simply supported at both ends. Usually the only time I have to use the between centres method is on crankshafts.

richard


Actually that is how I started finishing the part. Finally realized I didn't need to actually hold between centers. But I do have to turn the part around to finish, haven't learned how to cut in reverse yet... baby steps:)