Mortises, Mahogany, & The Sun

Article - May 31, 2011


Had a fun time in the shop today as I dove into the Adirondack Chair Guild Build. I started by milling up the front legs in preparation for the joinery and I immediately noticed some issues with the color of my 8/4 stock, but we’ll get to that in a moment. Once the legs were milled to length, width and thickness, it was time to cut the mortises. As is always the case in the Guild, I try to show multiple ways to do things. So I cut one set of mortises using a router, and another set using the hollow chisel mortiser. Which do I prefer? Good question Marc! The router method is a smidgen faster and results in mortises with nice smooth walls. With the sweet dust collection of my OF1400, the work is rather clean too. The hollow chisel mortiser is a bit slower, a little messier and the mortise walls aren’t quite as smooth. But it has the advantage of providing perfectly square mortises and built-in stops. So once everything is set up, I could literally bring a monkey into the shop to pull the handles for me. If you know any monkeys looking for work, please send them my way.


Now, about that mahogany color issue. Maybe its just my supplier, but the mahogany I have access to can be incredibly varied from board to board and purchase to purchase. This is not the first time I have been surprised to confront a board that is much denser and even looks significantly different than the rest of my material. Trouble is, this isn’t obvious in the rough stock (pictured left). As you can see, there isn’t much of a discernable difference between these two boards. But once milled the true colors really show (pictured right). The 8/4 stock is not only darker, but much denser. In fact, my first clue was during the jointing when I experienced quite a bit more chatter as I passed the board over the blades. So the real question I have to ask myself is, “Should I use this stuff in my project???” Obviously I don’t want the front legs look different than the rest of the piece, but the possibility certainly exists that natural aging would bring these boards into the same color family. Thankfully, the Arizona sun is quite powerful!

The Sun

I decided to conduct a quick test using three test pieces: a 4/4 board that represents most of the wood in the project, a single piece from the dark stock in question, and my backup stock that I stole from the Bell Forest kit that contains Fiji-grown Mahogany. I carefully placed the boards outside on my trusty “wood-aging boulder”. You DO have one of these don’t you?!?! After about five hours of unrelenting desert UV rays, the boards already started to darken. The results were actually enough for me to make a judgement call. The dark stuff was just too dark and I didn’t want to take the risk of this turning into a long-term eyesore. The Fiji Mahogany, on the other hand, looks perfect. And just in case you don’t believe the wood could change color in that period of time, the third picture shows you the tan lines. Hot! So it looks like I’m using the backup stock for my legs.

All in all, not a bad day. I’ll be back in the shop tomorrow continuing work on the legs and broadcasting live on the Live Page. Next up, adding a short tenon to the top of each leg and the Greene & Greene indent detail to the bottoms.