Inside and outside

[moojiefulagin]

Hi everyone! Has anyone ever found a way to copy an inside curve to an outside curve: what I mean is to take a shape, an oval for example, and using a template rout out the interior of the oval in a piece of wood. Then somehow use the ?same template? and precisely rout out an oval shaped piece of wood to fit perfectly into the space? What I would like would be a way to rout out an electronics compartment with a template & flush trim bit, and then make a cover that fits perfectly. Is there a way to do this other than freehanding the cover piece with guess and check? I hope I explained this well enough! Thanks a lot!

[Snork]

i think i understand what your saying. buy a template or make one. then route out the wood as close as you can get it. then use that same template to cut out the wood as close as you can to the template. and then if you cut it too small use wood filler. aka wood dust and glue. if you cut it too large shave it down. thats how you do that.

[moojiefulagin]

Thanks, what I was really looking for is some way to get it exact using a flush trim bit or something- you know without the guesswork. It seems impossible, but then again a lot of the things I get answers for here seme impossible too!

[Snork]

cnc routing is the closest to perfect that you can get but they are pretty hard to come by. (that is a friend who owns one) as they are 10,000 and up

[Drak]

I 'think' I know what you mean.

When building, if the situation allows for it, I cut out my control cavity cover plate out of the rear wood before I glue the wood to the body. Of course, this will only work if you're using a 'back plate' of wood. Like using a Maple back and top on a Mahogony guitar, know what I mean?

So I carefully mark out the area of the cover plate, then cut it out using my scroll saw. I start the hole using a utility knife and just making a slice thru the wood on my mark so there's no evidence of a 'starter hole'. I insert the scroll saw blade into that slice and just cut the cover out and save it until it's ready.

But what you are describing, if you perfectly copied the shape of your cover, the cover would just fall thru the hole, there would be nothing to suppoert it, no 'ledge', no 'posts' to hold it up level with the back of the body.

Make sense?

You can get a decent scroll saw for $100.00 at Home Depot.

Scroll saw blades can get so thin, you can put the piece of wood back in place and almost not even tell it was cut out. I use a slightly larger blade to leave a little room for the finish, else it wouldn't even fit back in it would be so tight you couldn't even put it in the same hole you cut it out of once you finish everything.

Once I cut the cover out and glue the back plate on to the body, I just use the existing hole as my pattern to route the cavity out, but I leave a ledge all the way around so the cover has something to sit on and a place to screw it down.

I believe that is what your asking about, and that's my way of doing it.

[frank falbo]

You could also just make your template Drak's way. Start with a 1/4" piece of something, and scroll saw your backplate shape. Now you have a backplate template you can attatch to your material and pattern cut around it, plus the "hole" template for the recessed plate cavity. The scroll saw width is just perfect. You don't actually want the exact same measurement otherwise the plate wouldn't fit properly, plus as the wood expands and contracts it could get stuck in there, or crack. I've made a few wooded backplates, and I laminate mine to plastic or lexan. That way I know the plate won't warp.