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View Full Version : Holding Knurled Aluminum Rod In Mill Vise



mattthegamer463
03-21-2017, 04:27 PM
Hey guys, I've got a project where I will be machining a flat on the side of a knurled part, but since it is aluminum I'm concerned about visibly damaging the knurl. What should I shim it with, or make some kind of soft jaws? Wood shims? Wood jaws? Leather? Part of the issue is the low surface contact area, should I try to cut a mating groove in a block to get more contact?

I'd love some tips.

- Matt

BCRider
03-21-2017, 04:30 PM
This would be a perfect time to drill the same size or next size up through a piece of wood then split it down the cut and use this as non marring jaws. If it's a short round knob then a wooden holder sized to perfectly hold the knob. The final shape would rely on size and shape.

If the length of the knurled portion you can hold is really short you may also gain a lot by using a machinists jack to support the other end.

MattiJ
03-21-2017, 04:58 PM
Hard wood, stiff leather and few layers of cardboard all come to my mind. You probably don't need anything extreme in clamping forces. For more than one-time use my choice would be baltic birch or baltic birch plywood machined to shape.

boslab
03-21-2017, 07:44 PM
I go fo the cornflake sheet these days, recycled HDPE, cheap, if it's cylindrical you could go between centres?
Mark

mattthegamer463
03-22-2017, 10:23 AM
I probably should have been specific that I am cutting the entire length of the part, on one side and also the opposite side, so I'll have to flip it and rest it back on a parallel after.

Sounds like some non-corrugated cardboard is a good start, should make it easy to use a parallel to get it flat and the parallel again to index the first face down for opposite side cut.

Thanks for the tips guys.

RWO
03-22-2017, 02:13 PM
I bought a sheet of this stuff years ago and still use it, mostly in the mill vise. It is indestructible and grips amazingly well. http://www.penntoolco.com/royal-magic-grip-vise-liners/

RWO

CCWKen
03-22-2017, 02:37 PM
You'll want something thicker than the depth of your knurling. HDPE, wood or most anything similar.

Yondering
03-22-2017, 04:28 PM
I probably should have been specific that I am cutting the entire length of the part, on one side and also the opposite side, so I'll have to flip it and rest it back on a parallel after.



Can you clamp the ends instead of the knurled sides? That makes it easier to square up on the parallels for the second cut anyway. That's what I've done in similar situations.

BCRider
03-22-2017, 04:48 PM
I probably should have been specific that I am cutting the entire length of the part, on one side and also the opposite side, so I'll have to flip it and rest it back on a parallel after.

Sounds like some non-corrugated cardboard is a good start, should make it easy to use a parallel to get it flat and the parallel again to index the first face down for opposite side cut.

Thanks for the tips guys.

If you've got length like that working for you then there's no issue at all. Cereal box card stock or similar heavy stock and a moderate lean on the lever will do just fine. If in doubt just double up the thickness with a folded piece. I'd use TWO pieces. One each side so the piece rests directly on the lower material used as your parallel. And simply don't beat it down like you would normally do.