Help w/ inlay-esque project

Ok, I'm about 95% sure this is due to my lack of understanding on the software side, but I'm having some issues cutting shapes to the size I need. Some background:

- Trying to "patch" a pinball cabinet that previously had two button holes (literally holes for arcade style buttons) drilled in an area where I need a single button hole between them.
- Wood filler may have worked but I was concerned about how sturdy drilling a new hole through it would be.
- Decided to do a 3d inlay out of another piece of plywood / pocket out the original area on the cabinet.

I've pocketed out the area on the cabinet to an acceptable degree, but cutting the inlay is causing me serious grief. Using VCarve 7.5 (though I'm more familiar with Fusion360 from a modeling standpoint but can't get the CAM working right) and the x-axis is way off, either about 1/2" too big (climb cut) or too small (conventional cut).

I know I'm not putting enough information in here, but at this point I'm not even sure what to describe. Here is an image (Dropbox) showing the pocketed component (that slight curve on the left side is from the original button hole - it will be filled / recut later.) The inlay is the reverse component (notice the lip to provide some support) - it fits perfectly on the Y axis, but the X is off as described.

I don't think this is too advanced of a project but for some reason it is causing me all sorts of issues - any ideas or help would be greatly appreciated.

Mike,
We are the same place with F360, I have gotten good to very good with modeling but can't use the CAM at all.

The good news is this is not a job for F360. It is a job for Vcarve Pro. I wish I was there, then it would be a peice of cake to walk you through it.

Let me try here:

open Vcarve and select new, from there you will be ask to set some job parameters. Set them as x=6", Y=8" and material thickness as the actual thickness of the plywood. Select top for Z zero and center for x and Y zero. click okay.

Now just draw a two rectangles, one the size of the lip and one the size of the main cut.

Now switch over to the other side of the program and we will program the cuts from there.

Select pocket and select both rectangles. Set the depth such that you will have the lip you need. click calculate.
close the preview and now select profile, set the depth just deep enough to cut through plus a few thousandths. make sure "outside" is selected for "machine vectors",, now click calculate. if everything looks good in the preview save your toolpath and cut.

Vcarve takes so playing with but is super fast for things like this once you get it.

Here is handibot take on this... [handibot.com]



Edited 1 time(s). Last edit at 10/03/2016 01:16AM by Mark Evans.

Thanks Mark - I haven't tried it quite like this yet, but rather individually setting the toolpath parameters for each rectangle. To make the replacement piece would I do the inlay operation instead of pocket?

Mike Wrote:
-------------------------------------------------------
>To make the
> replacement piece would I do the inlay operation
> instead of pocket?

No, you got it right in your OP, this is inlay-esque. The inlay operation is an advanced thing for making beautiful two piece carvings. You are just wanting to make a part to fill a hole.

Ok, got a lot further today - Thanks Mark!

- The method you described worked a lot better. The plug pieces I made had at least 3 straight sides (more on that in a minute) and cleaned up pretty well.

- Noticed that the cutter was chirping / skipping quite a bit as it was moving around and the bit finally came out. Swear I tightened it down but I guess not enough. Once I fixed that problem, it was a bit better but still chirped / jumped around.

- Noticed that the feed rate was 3in/s so dropped that in half and got a lot better result. Dropped it down a bit further and even better.

- Tried running another pocket operation (to make the cutout in the cabinet) and it came out ok but still having some fit issues between the components. Ran out of time to test out a few further theories.

Regardless I should get there soon -

Thanks again!

Glad I could help.

The loose cutter is my most common mistake, I watched a $10 piece of walnut turn to scrap that way just the other day.

You'll get this feeds and speeds thing, with a CNC router it is more art than science but with each cutter and material there is a window that gives the best cuts. Too slow is just as bad as too fast. And a sharp cutter is essential.