It's funny to me how complicated the simplest procedures can be sometimes.
In this case, I had to cut an arch for a detail piece on a built in that I'm installing soon.
First, I had to consult the Internet to remember formulas for chord length. I knew how long the chord length was, I needed to use that to chase back and find the radius of the arch. The radius I came up with was 15' 6".
Then I needed to make a trammel beam that would hook to my bench on one end, and mount to the jigsaw on the other.
Fifteen and a half feet is a long distance for an unsupported beam, so I brought out the trestle rails.
Last but not least was sawhorses, and a box beam to clamp to.
In all, about two hours of setup time. Two minutes later, the cut was done.
Using routers with guide rails is nothing new. But I like this setup for two reasons. If you want to run dadoes at a fixed distance from one end or the other, this is, again, easier than a table saw. And, I find the depth with a router cut dado to be more reliable than with a table saw. Sheets flex, it's hard to keep them firmly down. And cross- cutting dadoes with a table saw on long pieces like this requires either a really big sled, (ie, bigger than mine) or alternate but similarly excessive techniques. So, this table is great for production work in that direction.
Another little time saver is this router starting block. This is the first piece that gets cut with the router on the first pass. It tells you exactly where the router will enter the wood. Simply align your layout markings with the actual cut, and go. That saves a LOT of time that would otherwise get tied up in fussy measuring techniques. Good stuff.
And, again, this doesn't have to be quite so fancy. Using something simpler for the rail, and routing with a laminate trimmer would work, too. And the top picture above shows a simpler production fence than the Kreg setup: just some plywood and a clamp. I went with the Kreg because I think it's more robust and precise, but hey... Whatever works.
I pulled out my DW circ saw to demonstrate the point that this table isn't just for Festool junkies. It's for anyone who needs to break down sheet goods cleanly, to reliable, repeatable dimensions, but don't want to use a table saw, either because...
-They don't have room for in feed and out feed in their basement shop.
-This whole setup is cheaper than a table saw.
-Moving a circ saw over a table is easier on the back than moving a full sized sheet of ply, and more controllable.
I've seen methods for making a zero clearance plate for a circ saw. Some involve bolting on a piece of Masonite, or filling the plate with bondo. However you do it, with a zero clearance plate and this table, the veneers on both sides of the sheet will be supported. That means you can cut a finished edge in one pass.
For my next trick, I'll be using a router with this table, to make identical dadoes in multiple pieces...
A couple of years ago, I got a look at a cutting table over on the Festool Owner's Group message board, and I thought it was really cool. I bought a bunch of plywood to build a version of my own, but I stopped short. I looked around and realized that what I really wanted was the space, not more stuff, and so I shelved the idea, until now. The main difference between what I had planned to build then, and what I actually built today, is that this is just a work surface, not a full table. We have a 4x8 assembly table/plywood cart in the shop already, and eventually I realized that I could simply make an MDF top, and put that surface away in the plywood rack when it wasn't being used.
The idea is simple: the Festool track registers against two points, that hold it square to a fence that's equipped with a production stop and a ruler. So, rather than measure and lay out every piece, and clamp the fence down for every one, I can set the stop and make the cut. Done. And because the MDF is supporting the underside of the sheet, the veneer doesn't get ripped up so badly.
The reason to make this is simple, for me. I have a lot of 8' long pieces of plywood that are too wide to fit in my cross cutting sled. They're destined to be cabinet parts and shelves, but they need to be cut to length, and that with efficiency. Given the half a day that I lost throwing this together, the efficiency part may not be in evidence on this particular project, but I suspect that future projects will vindicate my decision.
For the average woodworker with a 'normal' circ saw, this is still something that can be approximated. There are clamp-on guide fences that can be used instead of the Festool track to do basically the same job. If you use a lot of sheet goods for production jobs, this might just save you some time, and make things easier on your back...
Well, it's been finished, I just hadn't had time to post it. The base finished up nicely, and refinishing the rest of it turned out well.
I'm really grateful to have had this project. One of the interesting aspects of cutting the semi- mitered joinery was that there was a LOT of precision involved. In the end, the blanks were out of square just enough after the jointer, planer and table saw, that the sliding table saw wasn't able to cut accurately enough. I needed a hand plane to get the blanks to be just so,
After that, all of the shaping work reminded me of just how skilled I am, and how much I'm able to rely on my hands when the limits of the ability to work accurately with machines is reached. Cool stuff.
There was a very strong element of 'be careful what you wish for,' in this one. I've had a yen for complex curves and complicated methods for a while, and, well...