Router template assistance

[Dan Bundy]

I'm making a box for a co-worker to place her cat's ashes in. Along with the ashes, she received a casting of one of the cat's footprints. My idea is to inlay the casting in the top. I've got a 1/4" straight bit that I'll use with a 3/8" guide bushing to rout the "hole" for the casting.

My question is, how do I get an accurate and properly sized template? So far, I've scanned the casting and printed it, as well as measured the casting and printed the scans so they should be about 1/16" larger to accommodate the bushing. The problem is the edges of the casting are sort of rounded from top to bottom, so the prints aren't sharp at the edges.

Here is what I'm trying to inlay: 326322

I know trial and error is a viable option, but my t & e usually goes "too small, too small, too big" so I'm hoping someone with more experience can provide some insight. I'll probably be using hardboard for the template. Thanks. DB

[Myk Rian]

Make the template using a spindle sander. 1/16" oversize with that bit and guide.
Make absolutely certain the bit is centered in the guide, and the guide does not move in the router base..

[Jim Dwight]

You can do it with template guides and router bits but you have to be a bit clever. I would use a little bit, like a 1/8 inch diameter, with a small template guide, like 1/4 inch OD to cut the template. double sided tape could stick the pawprint to the plywood I would use for the template. Then you need a bigger template guide to move the bit the same amount away from the guide as the first bit and guide cut oversized. If you use a 1/8 bit and 1/4 template guide then the template will be 3/16 oversized. So you need the template guide and bit combination for the inlay to move the bit 3/16 away from the template.

[Mel Fulks]

I would not worry about the rounded edges,the concept will be more effective with the casting a little above the box surface.

[Myk Rian]

Is that casting made of plaster, or something more durable? If plaster, you will want to sink it into the top, and place a clear cover (glass?) over it.

[Dan Bundy]

Thanks guys. Lots of ideas to consider.

Myk, the casting is "plaster-ish." It's lighter than plaster and seems a little softer, almost spongy, so I'm a little afraid to use it directly with the tools for fear of damaging it somehow. As you can see, it's also sort of irregularly-shaped. That's why I was trying the scanning/printing thing.

DB

[roger wiegand]

Here's how I do inlays: Tack the object to be inlaid down where it is to be inlaid, perhaps with double sided tape or a temporary glue (for pearl I use superglue then acetone to release, probably not a good solution for plaster), trace the edge with a sharp knife, like a pointy x-acto blade, rout the cavity to the line by hand using a small router like a dremel or foredom tool in a router base (strong light helps), glue the object in with epoxy mixed with fine sawdust from the object being inlaid (on ebony I just use carbon black rather than sawdust).

[Myk Rian]

Roger has it nailed. Freehand routing is not hard to do.

[Greg Hines, MD]

This is outside the box thinking, but if you know someone with a CNC, you could actually have the paw print carved into the top.

Doc

[Dan Bundy]

Thanks. That is an interesting idea. Unfortunately, I don't know anyone that has one. DB