Just when you thought it was safe to go out again, here I go again with the frame saw. This time, I wanted to fix some of the problems I’ve had with the blade-holding hardware. The basic problem is that the bolts I was using were too small for anything reasonable as a cross pin to secure the blade. I bought some 3/8″ bolts and threaded rod to go into the frame, then some stainless steel #4-40 machine screws and nuts to serve as cross pins. I used the same procedure to adapt the hardware as before, so I won’t repeat that.
I thought that I had to enlarge the holes in the frame for the new hardware, but it turns out that I needed to do it to just one of the sides–the other was already big enough (I don’t remember doing it this way). But enlarging the holes means that there’s even more of a weak point in the wood at the very point where it is getting the most stress. Beech is very strong for this application, but I didn’t really want to take any chances, so I resawed and shaped some scraps to bolster that point:
Then I glued them to the frame (with liquid hide glue, of course):
A couple of days passed (while I was working on other stuff), and I figured it was best to let the glue cure a fair amount anyway. When I came back to it, I decided that I’d also do something about the difficulty I’d been having keeping the blade straight while tensioning. It turns out that there’s a simple solution. I grabbed a cutoff from the stack (looks like this came from saw handle project) and sloppily cut a kerf halfway down the center:
To use it, just slide it over the blade when you’re tightening it up:
With these changes in place, I can get the blade much tighter with less work.
Oh, in case you’re wondering why there is a the hole in the blade securer, it’s an experiment in keeping everything together while in storage: