Saturday, May 12, 2018

Obscure Machining Question

I have a piece of 1" diameter,  7/8" high piece of brass I need to cut a 45 degree slice.   (It needs to be cut at a 45 degree angle to hold a diagonal mirror.)  The obvious solution is to mount the vise on a tilting table at 45 degrees and cut across.   The problem is that to make a 45 degree cut requires cutting 1.225 inches from the highest part of the cylinder but that goes below the jaws of the vise which jaws stick up .9" from the base of the vise.  I put various thicknesses of spacers under the workpiece to get it high enough to have room to mill off 1.225" from the top, but that is not enough spacing.   Any suggestions?

Thanks for the suggestions.  Mount a lathe chuck on the tilting table to hold the workpiece.   The lathe chuck does not stock up very hard,  and I can clamp down on the workpiece worth enough force to nor pop out.


Will said...

Can you counterbore a hole for a screw to mount the workpiece to a standoff that can be clamped in the vice? Screwhead needs to be located deep enough to be below your finished surface. Actually, you need two, although you can get by with one screw and one pressed in pin similarly located deep (to keep the part from rotating)

How are you planning on mounting the mirror holder? Could this center screw be used? Consider flipping the screw around, and putting the counterbore (if needed for clearance) in the standoff, and thread the hole in the workpiece (still requires two items to control rotation)

donumvitae said...

If this is a one off, try starting with a piece longer than you need, cut the angle, then flip it over and cut it to length.

Steffen said...

Use a hacksaw and miter setup?