Epiphany Induced OCD

During this apparent downtime, I've actually been raking my brain over some coals, trying like hell to figure out a way to make those 16" radii in plywood for the roof/walls. The obvious choice to me was bendable plywood, but it turns out, it's not easy or cheap to get to bend in the direction I need. Cross grain is easy, apparently, but rip isn't.

So I could try laminating thin ply, which still requires a ton of work and finding the right wood. It needs to be marine grade so that wetting the plywood prior to bending won't foul the adhesive that keeps the wood together.

That leaves the only option: kerf bending.

That's not much of a solution. Kerf cutting is when you make a series of grooves in thick wood close together so that you can bend it easily. The huge problem with this is I would need to make these dozens of cuts all along the 8 foot length of the panels for the roof. By my estimate, I need two 35" wide x 8' long panels, depending on how thick I want (hur)

kind of an extreme depth but this is how you kerf bend.

Now, if I had a massive table saw, I could probably do these cuts down an 8 foot length. It's really just a matter of the fence being in the right place and a bit of care and patience. But my table saw sucks and is way too small.

Since my bend is a pretty generous radius, I wouldn't need so many cuts, which made me think of a circular saw. My first idea was to mimic a table saw by making a big, heavy fence that would sit on the panel and I could just rip kerfs as I pleased. The practical problem of not being able to get a reliable fence for that length squashed that plan. Then I thought I could just snap chalk lines and cut them freehand. I mean, you can only go so-freehand with a circular saw as all they want to do is cut straight-ish. But then it hit me, and me being me, this is all I can think about today:

What you see is the exploded view of my circular saw. Item 79 is the existing base plate (shoe) secured to the depth setting hardware with screws (item 72). I can make a plate that attaches to the underside of the shoe with the same bolt pattern. Replace screw 72 with some that are a bit longer and make this plate something like a zero clearance insert for a table saw. An inch or so from the blade, I can press in a straight line 4 pins of  the same diameter as the width of my kerfs.

What this gets me is this: I cut 1 kerf free along a chalk line or a fence or whatever. Then, I install this jig. The pins will ride through the kerf I just made and guides the next cut. It's like an instant fence- each kerf is parallel    and evenly spaced.

Totally do-able.

Maybe pictures next time.