Keeping sharp corners when sanding

Tools, Techniques, and Reference Materials Techniques
1

I can’t seem to keep the sharp edges when removing ejector pin marks and seams. Commercial sanding sticks use foam as a backing so that doesn’t work very well. I’m gluing sandpaper to wood blocks (might try metal bar stock), but still am having trouble keeping the block perfectly parallel or at right angles to the work. It seems that the smaller the piece, the harder it is. Maybe this just needs a certain technique, or practice. I’m remembering the nice sharp edges achieved with a belt or disk sander in woodworking.

Anyone have advice or a technique that works for you?

Thanks,

Dave

2

See if this helps …

Paul

3

Thanks. Excellent advice. The direction of sanding was most helpful. I thought I might try afixing sandpaper to the inside of a piece of aluminum angle and using that to keep the part at right angles. Anyway, there is much good advice in that video. I learned a lot.

Thanks,

Dave

4

Dave;

What I do if the divots and parting pin marks are on a flat piece is this . I put it in a jig made of the same thickness of Evergreen plastic .Then when I sand it is all flat ,with no chance of rolling over an edge .

Been doing it this way for years . I also use the adjustable pencil sized sander . This primarily for tight spots . Also if the pin marks are too deep you can use a craft punch and punch out a disc out of thin ( .010 ) and insert it in the hole and sand it to match the surface .

5

Very good thinking. I was thinking of a jig but didn’t consider allowing the jig to be sanded with the piece.

Thanks,

Dave

6

I mask with tape right down onto the area, within 0.10 inches, of the ares to be sanded.

7

This video proved to be extremely helpful. Thanks. Taping the sandpaper to an acrylic block and sanding in one direction only, improved results dramatically.

(There was some cussing trying to cut acrylic[8o|])