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This weekend I was using my shavehorse to make some wooden spatulas. After a while, the head started losing grip on the pieces I was working.

To help improve the grip, I wrapped a piece of leather around the top crossbar and tacked it into place. While I don't have a picture of this, you can see the crossbar above the platform in the image below.

enter image description here

Adding the leather seemed to help a bit, but the issue still remained. Looking a little closer, I noticed that the surface of the platform was getting burnished, which would explain why it was so slippery.

At this point I was out of time to work on stuff, so I set it aside. I could add another piece of leather to the platform, which would probably help with grip. However, I'm curious if there are any other ways that I might increase the grip of my shavehorse.

grfrazee
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    give it a light sanding with a coarse grit? – ratchet freak Aug 03 '15 at 13:30
  • Yes, this will probably work in the short term (i.e., for one session of shaving, until it gets burnished again). However, I'm really looking at something more permanent. – grfrazee Aug 03 '15 at 13:32
  • Grip tape maybe? Although if it the work moves then it would have the same effect as the sand paper. I also feel that the board holding the piece down could be made heavier to allow gravity to do the work for you. IIRC First shave horses were made out of logs. – Matt Aug 03 '15 at 14:39
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    You are right, primitive shavehorses were (and still are) made of logs. The bodger's-style horse I made is made to be easily disassembled and transported. The extra weight of the "dumbhead' for a log-style horse would add some grip due to its weight, but the majority of the gripping force comes from the leverage of one's feet on the swinging arm. – grfrazee Aug 03 '15 at 14:50

6 Answers6

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To help improve the grip, I wrapped a piece of leather around the top crossbar and tacked it into place. ...Adding the leather seemed to help a bit, but the issue still remained.

I suspect that the leather is one or both of the following, 1, too thin, 2, too smooth (much modern leather has a glazed surface and not inherently suited to this application).

You could try using the flesh side of the leather you have, but in addition or instead of this I think you should pad the leather from the back so that it can deform around the workpiece more and that will improve the grip substantially.

I'm curious if there are any other ways that I might increase the grip of my shavehorse.

Push with your legs harder.

It sounds too simple but this is precisely the mechanism that the shavehorse/shaving mule is designed to take advantage of.

This should sort of happen naturally as you work the wood so it may indicate you're sitting a little further back on the bench than is ideal, so that your legs are initially more extended than they should be.

Graphus
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  • I don't know the thickness of the leather in terms of weight, but it's over 1/8" thick, and I was using if flesh-side out. It's chrome-tan if that makes any difference. Using padding is a good suggestion. Also, you're probably right on the leg pressure part - it was near the end of my session, so I was probably tired. Additionally, there's not much of a back stop to the seat, so I don't have anything to lever my back against. – grfrazee Aug 04 '15 at 12:16
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Of course my first suggestion would be to use a little sand paper, that is a quick and easy solution.

More long lasting my be to put a coat of rubber cement on t and let it dry.

A different approach might be to glue a rubber mat on it. something like piece of innertube might work well

bowlturner
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  • Would the rubber cement cause any issues later with finishing? Also, I wonder about the possible toxicity of rubber cement with items that are destined to be used for eating, but i could be overthinking it. – grfrazee Aug 03 '15 at 13:38
  • I was going to mention that. it might leave some residue on the work piece, but I really don't know. – bowlturner Aug 03 '15 at 13:41
  • Rubber cement is latex based (the same chemistry as house paint) and although not something I would recommend drinking, not very toxic and easy to clean with water. I would have no safety concerns with using it as a coating on tooling to make eating implements that would not be addressed by basic cleaning of the finished part (air blow off with clean air or water). I would be concerned it may not last or work as well as you hope. – hildred Aug 04 '15 at 05:03
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Classic solution for modern jigs and pushsticks is to apply self-adhesive sandpaper to the gripping surface. Various high-friction rubber materials are also used. Not sure what would be best "in period"...

keshlam
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  • I'm not concerned about being "period correct" as far as materials go. I'm using zinc-coated steel rod and fender washers, for crying out loud :) – grfrazee Aug 03 '15 at 16:03
  • Understood, not a critique, just pointing out one situation where my suggestion would be inappropriate. After all, for all I know this is just your prototype... and I do have friends who try to be purists when they can. – keshlam Aug 03 '15 at 16:23
  • No worries. Who knows, I might decide to do a re-enactment some day and want to do it "period-correct." – grfrazee Aug 03 '15 at 21:54
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It may just be the perspective or the setup of the photo, but it appears to me that your shave horse is not adjusted quite right. When you push on the footrest, the swinging arm should not have to travel very far past vertical, and the grip should not be able to swing closer to you than the platform.

You should either use a taller platform or, better yet, you should move the grip further down on the swinging arm (with your shave horse, this will mean adding more holes). In your comment, you also mentioned raising the pivot, and that would be even better than simply lowering the grip. Either of these adjustments to the pivot will give you significantly more hold-down pressure without having to exert more force on the footrest.

As you might recall from grade school or high school, your mechanical advantage with a lever is the ratio of the lengths on either side of the pivot. So if the footrest is 24" and the grip is 12" from the pivot, you have a 2:1 mechanical advantage. If you bring the grip down to 8" from the pivot, you now have a 24:8, or 3:1 mechanical advantage. If you instead raise the pivot by 4", your mechanical advantage is 28:8, or 3.5:1 (i.e., 3.5). Raising the pivot point even higher will amplify your hold-down pressure even more.

One final suggestion: make sure your platform is not too smooth. It shouldn't be necessary to add friction material; but if you do, add it to the platform that the workpiece rests upon, rather than adding it to the grip (top crossbar).

rob
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  • I have been meaning to move the pivot closer to the seat-end of the horse. You make a good point about the travel of the footrest. I'll have to try some iteration of moving the pivot point higher (maybe on a block above the seat platform) and moving the pivot closer to the seat. – grfrazee Aug 04 '15 at 18:50
  • @grfrazee Moving the pivot point higher will definitely help. I'll add some more details in my answer. – rob Aug 04 '15 at 22:24
  • Increasing the mechanical advantage of the shavehorse ended up being the major contributor to holding power. While all answers were helpful, this ended up being the most helpful. Thanks @rob. – grfrazee Sep 01 '15 at 13:08
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Sharpen your drawknife.

This isn't a complete solution, but if you look at the question as "how can I reduce the required gripping force" instead of "how can I generate more gripping force," the obvious answer is to make sure that your tools are as sharp as possible.

Caleb
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I don't have and never used a horse but I have seen many in use and done some previous research.

Leading with my weak suggestion you could use grip tape on either or both sides of the table and clamp/hold. That would have the same effect as sand paper on the work piece so might not be desirable. It should however last longer.

Perhaps you just need to increase the surface area that touches the work piece. Other bodger-style horses that I have seen have a larger a larger block that the work sits on. If that same block was angled that might help get more of a grip as well.

Another suggestion would be to change the head out for a heavier wood and let gravity help you. You are correct in your comment:

the majority of the gripping force comes from the leverage of one's feet on the swinging arm

But I think the strength of the lever and head and the joint that connects then would make it so you could add more pressure.

I'm surprised the leather did not help.

Matt
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