# Rounding off jig--(again)



## Brian Rupnow (Nov 9, 2008)

About 9 months ago, when I first decided that I wanted to play machinist, I bought my lathe. Then, I decided I could do milling in my lathe, and against the advice of more experienced and wiser heads than mine, I bought one of those cheap Chinese 2-axis slides--You know, the $35 ones. Of course, it didn't really work worth a darn and I ended up buying a milling machine. My rounding off "by eye" leaves a lot to be desired, so today when I went to round off the end of my piston rods, I resurected the Chinese 2 axis slide and mounted it on my old drill press with a sanding drum in the chuck. I had a peice of 1" square aluminum bar with a 1/8" hole reamed in the end of it, so I chucked it up in the Chinese thingy and slid the end of the 3/8" square brass bar (which I had drilled and reamed a 1/8" hole in the end of) it over the pin, then advanced the Chines vice untill I had contact between the end of the brass square bar and the sanding drum. then I swung the brass bar back and forth 90 degrees to either side. Man, did it ever do a nice job of rounding off!!! This is not an original idea--I seen it before on either this or the Home Machinist website. It just works so darn nice, I thought I would bring it up again.---Brian


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## wareagle (Nov 9, 2008)

Brian, excellent idea! Thanks for sharing!!


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## Maryak (Nov 9, 2008)

Brian,

I've got one of those Chinese dohickys too. :

Thanks mate now I can use if for something other than a paperweight. ;D

Best Regards
Bob


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## bentprop (Nov 9, 2008)

"I've got one of those Chinese dohickys too. Roll Eyes"

Same here.I found it is moderately useful if you lock both axes before drilling.
There was an article in one of the model magazines a few years ago on improving said appliance.It involved replacing the main acme screw with an opposite handed one.If you were going to go to all that trouble and expense,you might just as well buy a decent vise in the first place ???

Good idea on the rounding,Brian.I'll store it in my brainbox for future reference.


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## Philjoe5 (Nov 9, 2008)

Good idea Brian. Thanks for the pictures showing the usefulness of a tool many of us bought but few have actually used. I usually do this rounding on the minimill (Sieg X2) with an end mill but I like your idea. This'll get some of the cob webs out of the drill press.

Cheers,
Phil


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