I didn’t get to making any more gap-toothed WV-looking dovetails last night. I figured out a way to fix my twin screw “Moxon” vise.
Since I am not one to spend money on stuff I can make, I made the vise using 2 crap (read as cheap) Shopfox veneer press screws. At $20 each, they come in far cheaper than the hardware kits online or getting Acme screws, nuts, and handles from McMaster Carr. Actually, MMC is pretty inexpensive on the screws and hex nuts. But crazy expensive on handles and flange type nuts. So I figured I can make this work. And it did, after a fashion.
The flange is buried in the back jaw so the front of the vise only ever has the handles sticking out, not the extra length of screw, like some kits online have. That strikes me as crazy considering where that steel screw would strike me if I wasn’t careful.
I had large washers in the front jaw to act as a wear plate against the handles. It worked fine when tightening, but the front jaw had to be manually pulled back when opening and a bit fussily since the screws are 18″ apart, you have to keep it relatively square or it would bind. What I wanted was the front jaw to stay associated with the handles, but couldn’t see how to do it with the hardware I have.
That was 2 or so years ago, whenever I made the vise. And it hung on the wall until I started the Great Dovetail Learning Project and realized that’s the perfect vise for this. So, now that I am using it again, the jaw thing really started to annoy me.
After a little surfing of Google images and Pinterest and I had a notion that might work. If I could capture a wide washer between the handle and the start of the threads, I could screw that to the front jaw and it would stay put. Luckily, a 1/2″ washer fit over the ovalish handle mount and just barely won’t fit over the threads, so I was in business.
Drill and countersink some holes in the washers, remove the handle, place them in there, and replace the washer. Of course, the retaining pin no longer lines up, but that’s what drills are for. It’s not pretty, but metalworking isn’t my forte, so we’ll go with it. And the 1/2″ washers aren’t nearly as wide as the 3/4″ washers I had sunk into the jaw as wear plates, so it’s a bit meh.
Now to test it.
It was too late in the evening to start some dovetails, so I just did some sawing practice. The most critical aspect of sawing out dovetails is getting it square across the board. The slopes of the tails can be at any old angle or collection of angles (take a look at some antiques sometimes). But if the width isn’t square to the board, you’ll have a hell of a time getting the joint to work.
According to the Internet gurus, as long as you’re within 1/8″ of square over ~6″, you’re good to go as that works out to less than 1/64″ gap worst case. Much more than that and you’ll want to pare that square before marking the pin board. It’s harder than you’d think. Hence the practice.
I did have an ah-ha moment playing around with it. The rake of the teeth matters, a lot. Looking down on the cut line, I tend to start at the back edge and then work down towards me. That makes it easy to see the line. But the saw hates it. And I have a nice saw that’s pretty sharp so I couldn’t understand why it was complaining in the cut.
Well, if you start at the back edge, things work just fine. Why? Now the heal of the saw is lower than the toe and the teeth engage at almost 90 degrees from how they do the other way. And, as it turns out, that’s why they are filed the way they are. Huh.
It doesn’t matter as much with crosscut saws since the fleem of the teeth make up for it and most of the non-dovetail cutting I do is all with a crosscut saw of one sort or another.
(For the non-woodworkers who are still with me here, the teeth on dovetail saws are filed for rip cutting (along the grain), most other saws are filed for crosscutting (across the grain)).
With that nugget of wisdom learned, cutting proceeded much better. This is one of the little things that you’d have learned if you learned woodworking through apprenticeship rather than by reading books and watching YouTube…
