Shaving bench - lateral stability and gripping questions

[Jeff Skory]

I built a shaving horse a month ago (Shaving Horse (http://sawmillcreek.org/showthread.php?t=134223)) and have just started making some good use of it for shaping some cabriole legs.

Now, first off, it's not the world's sturdiest shaving horse. But one of the problems I was having is that it does not always grab hold of the leg super tight. Part of the problem is that the part I am grabbing (the leg block) is still square so it is simply flat pieces of wood clamping against each other.

I glued some strips of leather on the bottom and on the yoke (square swiveling clamp piece at the top). The top piece had not finished drying yet so I only used the bottom piece which helped a bit.

Does anyone else use leather or is there a better method.

A second, but related question deals with lateral stability. While holding the leg in the shaving bench I was moving a rasp from side-to-side in the ankle area. The leg tended to move around quite a bit, and the treadle frame also tended to twist a bit.

btw - I had to look up all those terms :D

So....how to I keep the piece (leg) from sliding sideways when using a rasp from side to side? Do I need to build a sturdier shaving bench? (yet another project lol)

[David Gendron]

I put leather on the yoke of mine as well as the bottom part, were the piece to be work rest on. the other thing I did, is to put a V groove the lenght of that bottom piece, so it prevent the work to move around and add some surface so add some friction. I have seen some with V groove on the yoke as well! Other than that, your shaving horse look realy well made. One thing maybe, I would have put a little more splayed to the legs in the two planes, going to the side and forward for the front legs and to the side and back for the back ones!
Hoppe it helps!

[Jim Koepke]

My thinking was about on the same line as David's of maybe a v-groove in the bottom part of the holding set up. My other thought was you could drill some dog holes in it to use with wedges to hold a piece side to side while it is being worked.

jim

[Mike Hutchison]

Recently finished a shaving horse; when I went about trying it out I was not real happy with the gripping power. So far have come up with two
things to improve this. Number one - I was trying to work on pieces that were very short-12" or inches or less. Reason for this length was attempt to get "straight" sections of oak and maple branches that could be mounted on the lathe and expected to turn reasonably true. Number two - made three "holders" (see pic) one for square or rectangular stock and two for roughly round stock in 2 different diam./radius that I thought would be common workpieces for the horse. Haven't had much time to use the horse but, longer rectangular stock with the holder for same has produced stable result. (No pun intended)

[Robert Rozaieski]

Jeff,
The first problem you might be having is simply with the physics of the shaving horse. The way a shaving horse is designed is to resist a force pulling toward you, as when using a drawknife. As you pull toward you with the knife, the opposing action of pressing the treadle with your feet clamps tighter. So the harder you pull, the harder it clamps.

The problem is, there really is no opposing lateral force except friction as the shaving horse really was not designed to be used in that way. To help with what you are doing, cut a "V" notch in the yoke so that the leg can be held on edge.
http://www.greenwoodworking.com/_/rsrc/1252289325348/ShavingHorsePlans/sh1.jpg

This will help some, but again, because working laterally is working against the physics of the shaving horse design, you are still going to get some lateral movement of the leg if you work across the grain with the shave horse. A more secure method of holding the legs for shaping with rasps and files across the grain is to use a handscrew clamp with a "V" notch cut in each jaw, and then to clamp that handscrew in your bench vise. Another option would be to put the leg between the heads of a pipe clamp and then put the pipe clamp in your bench vise.

As for the racking of the treadle frame, again, it's because you are using the horse for a purpose it was not designed for (working laterally). The treadle frame is solid against forces in line with the bench, as it was designed to be. However, if you are working laterally across the frame's joinery, racking is basically unavoidable. Think about it in terms of the M&T joint for the table. It's solid against forces pushing down from the top of the leg or against forces pushing from the front of the leg, but put the tenon in tension in line with the apron and the tenon will pull out of the mortise. Same thing is going on with your treadle frame. By working laterally across the horse, you are working in the weakest plane of the joinery.

In order for the treadle to pivot on the cross pin, and the yoke to spin freely in the frame, there has to be a very little bit of play in the joint. This is fine when using a drawknife or spokeshave to work in line with the bench surface. However, it makes it difficult at best to work across the bench's surface. But, if you make the joinery tight enough to resist lateral racking then the treadle frame won't move.

So I'm sorry to say, but I don't think there is a way to "improve" the shaving horse to better secure stock for working across the bench, without rendering it practically useless for it's intended purpose, working effeciently with drawknife and spokeshave in line with the bench. It simply wasn't designed for what you are trying to use it for. I think it would be better to try a different method of holding the leg stock for shaping across the grain.

[Jeff Skory]

Dave, yeah I would have liked a little more splaying in the legs as well but it is actually pretty stable leg-wise.

Jim, I have a v cut in the yoke but not in the base board (not sure of the term here). Good idea with the dog holes.

Mike, very clever idea with the replaceable holders!

Bob, I pretty much knew the answer, I just thought that maybe someone had come up with a method of adding lateral stability. :D Guess I'll have to use your clamp trick in my leg vise like I did with the first set of legs. And that means I'll have to stand up to file it. sigh.... ;)

[John Schreiber]

I built a shaving horse last fall and I've found it a bit underwhelming. Robert's points seem very true. It is more of a one trick pony (horse) than I thought it would be. It isn't much use for holding work except if your are pulling straight along the board. I built mine by eye and I plan to play with the geometry a bit to see if I can get more force. I find that wood often slips even when being pulled directly toward me.

In the good old days, I'd go to my neighbor and try his, but I've never actually seen another shaving horse in the flesh, so I'll keep experimenting.

[Jeff Skory]

Another quick update - tonight I was able to use the leather strips on the bottom plank and on the yoke. Held the piece nice and tight. No slippage this time.