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View Full Version : Where can I find a new drawbar?



SWATH
07-26-2015, 10:18 AM
The threads have finally stripped on mine and now I can't hold some of my tools.

slowtwitch
07-27-2015, 05:51 AM
I make my own. I'll post some info later tonight :)

SWATH
07-27-2015, 09:48 AM
I make my own. I'll post some info later tonight :)

That's what I figured. Do you make from scratch and from what material?

slowtwitch
07-27-2015, 11:31 AM
I buy grade 8 bolts (7/16x20) from Mcmaster (part # 91257A487). Look at the pdf, (don't mind the bad pdf drawing, I'm a rank beginner at this cad stuff), but it will give you an idea of how I made mine. The hex is 5/8" 4140 , also from Mcmaster.

The intermediate part is made from some round stock I have laying around. I turned it to act as a guide for the hole at the top of the spindle nd to help in releasing the collets.

In my situation, using my power drawbar thing, I hardened the Hex portion and use two roll pins to hold it in place (the pdf does not show the holes on the end of the bolt) . The harding really helps with using a power drawbar.

All the sizes are approximate (I'm at work and I just winged this from the top of my head :)

SWATH
07-29-2015, 11:27 PM
Thanks Pete,
I ended up having a friend make pretty much an identical copy on his lathe. Once I got it I realized it needed a minor diameter tweak and rather than send it back and since I don't have a lathe I did it on the machine using it as a vertical lathe.
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SWATH
07-30-2015, 04:06 PM
I machined the hex today and opted for a 3/4" drive to match my vise, I then heat treated it with a MAPP gas torch and used motor oil. I'm now tempering it at 350F for an hour. This one is made from 1215 steel but next time I'll use 4140.
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slowtwitch
07-30-2015, 05:22 PM
Nice job, Jim !!!!

bill south
07-31-2015, 08:36 AM
That turned out nice!
Bill