For inlays using butt-joined-objects that have two pieces, inverting one pattern corrects for adjoining cut bevels thereby giving a tight joint. Assembly of more than two adjoining pieces, having such alternating bevels, requires cutting two opposing bevels on one part.
The example shown has alternating bevels on the top piece. A cardboard template was cut for aligning the piece after the first cut. That first cut left a small sacrificial rectangle to be removed at the second bevel cut.
Yep, that’s common knowledge, (and he mentions it in the first post), but I might have misunderstood what was going on here…I thought he was talking about adding a gradient edge bevel. (Either way though, it probably belongs in the tutorials section.)
So you mentioned kerf compensating for the second cut in your cardboard. I am guessing you’re doing that to ensure you’re not off by a kerf or so with a plain flip, and therefore are using a jig that accepts a mirror-image kerf compensated hole for the dark wood piece?
If so, it seems like this is fairly fiddly, I wonder if there’s a smoother workflow? Did you get it right the first time, or was there some trial and error?
The right-side piece showing all cuts with the same inverted bevel (marked “1”) also needed a cardboard template in order to score the chain pattern on the other side. The kerf correction on that template was not quite right allowing the side piece to move slightly, so the chain score was a little off. I had previously made the three-wood pieces without the double bevel cut on the top triangular piece. The misfit gave me the idea to try correcting it.
What you’re doing is definitely a challenge, getting sub-kerf accuracy out of a cut template is always going to be tricky.
One thing you may not have seen that can definitely help you is what I call the “constrained symmetry border cut double sided jig system”. It’s a lot of words that say that you do a double cut where the first one is symmetrical on a specific axis (or two-three axes, it doesn’t matter, so long as it’s constrained some). Jules wrote it up ages ago, and it’s as good advice today as it was then.
In this example, she chose a rectangle (2 axes of symmetry) to constrain the circular final cut (unconstrained symmetry, so alignment is nearly impossible).
I’m sure you’ll see how this could remove your intermediate cardboard step.
That cardboard step was done with a kerf adjustment on the cardboard template to try for an even better alignment. I have gotten jam fits when the kerf adjustment is correct.
The ancillary square route is nice and the bevels on the square and template are matched. But there is still have a small kerf error. Probably would have been best to use that route anyway.
There’s a way to do it without kerf adjusting but it requires lots of steps and making a square jig with traditional cutting methods with a perfectly 90 degree cut profile. In the end chasing thousandths like this has a break point where it’s not worth the effort… experimenting and manually kerf adjusting can definitely be the simplest solution.
Looks like you got it worked out, really nice result.