Hi @Wayne311,
You are saying two things:
and
If you really don’t want to machine the stock sides, then you would need the two pieces of stock to be exactly the same size (I’m stating the obvious, but two pieces of raw stock rarely have identical dimensions, unless you buy them specifically to be within a known tolerance of target dimensions)
If they ARE identical, then it “only” becomes a matter of having a precise way to reference the stock on the wasteboard for each run. You could e.g. use a corner square, that would allow the two stock pieces to be referenced to the exact same location. And then zero off the corner of the stock before the first run.
If they are not identical to begin with, your best bet will be to machine the sides too to bring each piece down to the same final outer dimensions.
Other than that,
- don’t re-home the machine between runs, there is always a risk of introducing a tiny offset when doing that.
- do a thorough mechanical check of the machine to remove any slop
- use conservative feeds and speeds to mitigate the risk of lost steps during the first run.
For it to be perfectly seamless, it will probably take a few (…) trials, so I would suggest to do test runs in a soft material, to make sure it works fine in that “easy” case, before proceeding to cutting aluminium. I would probably try to run the jobs in Renshape, there are some 3"x5"x1" pieces on the store for example.