Front plate
This is a pretty self-explanatory process – first I need to cut the plate to size, then cut the dovetail joints to fit it to the sidewalls. The sizing of the plate is fairly straightforward – it’s the height of the sidewall pieces above the dovetails – in this case, the sidewall stock is 2″ wide, minus 5/16″ for the sole, and another 1/16″ for peining material. So the remainder is 1-5/8″ tall (I measure the piece itself as a check). In width, the plate needs 2-1/8″ for the interior of the plane, with 2 x 3/16″ for each sidewall, and an additional 1/8″ for peining material on either side – this gives me a width of 2-5/8″.
and then they’re filed. Flip the plate and repeat. Next, mark the ‘pins’ from this piece at either end of the sidewall stock… pay close attention to the orientation that will result after the bend – there is nothing more frustrating than cutting a perfect dovetail that is flared in the wrong direction, scrapping a sidewall piece you’ve already got a half-dozen or so hours into… or so I’ve been led to believe.
Here’s the fit of one side. Ideally, you want this fit tight enough that it requires some light hammer taps to seat or remove the piece – that makes for very easy peining later on. In reality, you can get away with a good bit more slop than that, but it’s a lot more work later…
Bridge tenons
It is infinitely easier to fit the bridge tenons before bending the sidewalls, so I cut the bridge piece from 5/16″ stock, and cut/file the tenons in place. I will finish the actual shaping of the bridge a bit later, but for now I want to get the fit for the bridge correct before I bend the sidewalls up. The tenons themselves are really straightforward – cut, remove some metal, file a bit and – voilá! The only tricky part of this exercise is filing the shoulder in place on the tenons. Once I’ve got the tenons themselves cut I have to remove about 1/16″ of material from the top face of each . This gives a nice shoulder, and a substantially nicer aesthetic fit to the bridge when the plane is completed. Here’s one side of the bridge, ready for the shoulder operation:
What I’ll do is use the vise jaws as a guide to cut to depth with my hacksaw – this will make it much easier to get the filing depth correct in a minute. I’m careful not to cut deeper than my 1/16″ depth, as cuttin
g beyond that point will substantially reduce the strength of the tenons:
Once the cut is made, I use the jaws again as a guide, this time for a pillar file used horizontally to remove the face material from the tenons ( you can’t actually see the tenons behind the file, but trust me – they’re there.)
Once you’ve gotten to depth, flip the bridge and repeat on the other side. A few test fits and refinements, and you’re left with the bridge piece looking something like this:
Be certain you have a perfect test fit on either side of the sidewall piece (and pay very close attention to orientation). You want a fit that is easily pressed in place without much resistance, but not too sloppy – you must be able to get the bridge in place after the bending operation without too much trouble. Here is one side’s test fit:
David Weaver says
Raney – any tips for getting the secondary dovetails to be a consistent size? Do you just scribe endpoints and join the line with something small as a makeshift straightedge?
Thanks to your discussion of files several weeks ago, I finally have the right files for the secondary dovetails and tight work. While fitting handles to the grobet pillar and barrette files, I think I heard the Jeffersons Theme in my shop.
Best –
Dave
raney says
Hi David,
Glad to hear you've made it to the East Side. Like a lot of things, you can make planes with almost anything, but every tool upgrade really makes a difference in how easy and quickly you can work…
As for the secondary dovetails – I generally scribe a line to represent the bottom of the sole, so I don't waste space dovetailing the peining waste. From that point, I scribe the dovetails with a small bevel gauge, which gives me consistent markings. The truth, however, is that unless you're going to use machinist-grade layout tools and techniques you'll always end up with some variations if you just go right to the line. What I suggest, which Konrad Sauer repeats like a mantra, is to trust your eyes.
If you have a good light source, you can 'see' if the dovetails match up with really remarkable precision if you trust the eyes. I work to make sure I've got a consistent 'rake' angle on the barette as I work (the rotation off perpendicular) and that I stick to a consistent plane as I file. This means that I'm generally making reasonably flat 'triangles' as I file. The eyes are very very good at keeping these consistent – much more accurate than my scribe lines generally are.
Also, however, bear in mind that the material you're using is an important variable. I'm working steel-to-steel, so the dovetails are going to be all-but-invisible. I don't waste more energy than I need to worrying about the aesthetics of the secondary dovetails here – I focus on making sure they'll do their structural job, and the appearance generally comes out just fine.
When working with bronze or brass sides, the dovetails are going to be much more visible – but again, keep in mind that if you're doing these by hand, you probably aren't really looking for CNC-grade precision. My feeling is that if the dovetails are all fairly consistent in size and angle, then small variations are just fine; they're an indication of the handwork that went into them.
Hope that helps some…