New year, new horse

Well, I’ll be blowed, now I can understand perfectly why so many people prefer the dumb head shaving horse.  I’d been getting a bit irritated at the way wet deer legs (OK hazel branches) were inclined to rotate while working a tenon up with a rounder plane so I thought I’d take the plunge and convert my donkey into a horse.  Here’s the old fellow:

This is an old photo, and I think all parts but the front leg and the bottom footrest in the frame were replaced by the time I converted it.

Here’s the new un:

I used the legs and bed from the old one.  The treadle is a little high on the dummy, but I was following plans.  I’d really like to add in about 6 inches to the middle of the lever/treadle, my Sunday apprentice Rich may find this one a bit cramped 😦

Anyway, I measured up the comparative leverages of the two horses and the old English frame version gives about 1:1 advantage (i.e. none) while the dumbhead gives about 4:1 mechanical advantage.  Now why would anyone use the frame one with such poor pressure?  Bit like using an axe without a handle!  I feel longer legs coming for the stock knife ‘bench’ ( AKA ‘stock’ – that’s presumably how the knife got its name, the favourite first task for an apprentice joiner was making his sawing stock).  Longer legs would mean less bending when using the knife.  Fortunately the stock knife I bought as a clogger’s knife seems to be a peg maker’s knife as the handle is hardly swept compared to a clogger’s which is severely bowed, and increases the back bending effect.  Poor old bones.

So I also managed today finally to ‘install’ the new extension stove-pipe that David gave me, well I say install, rammed it into the old pipe and wired it to a shelter member at the top to keep it away from the tarp:

Much healthier having that smoak outside the shelter.  You can see the 75 foot ‘leg’ of my pole lathe in the picture above.  It’s a felled beech tree that’s been down about three years now and is doing its job playing host to various fauna and flora and these (which seem to be neither):

And these:

These are on the stump:

And amazingly, there is a little regrowth from the stump too which I missed when it was in leaf:

I spy the buds ready for Spring

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3 thoughts on “New year, new horse

  1. Hi Richard,

    Nice conversion on the horse.
    Why is it that the dumb head design is more efficient? I first thought it that it really didn’t matter much. More a matter over leverage so to say. When you push on the paddle with force X it is transferred to the clamping part by the amount difference in the lever. The dumb head and the other design seem to have the same ratio. So when I made mine, I just made on of the non-dumbhead design because those are the ones I saw in use. Maybe because the head stick out from the lever it gives extra force. (this forces-vector thing was not my strongest point in physics)

    In retrospect I should have chosen the dumbhead design just because of the easier way of feeding the wood into the clamp from the side. Instead of wrestling it in from the front while doing some yoga exercises.

    • Hi Erik!

      Some teachers eh? Levers are so important to help us out. If you had somewhere to rest a very long pole you could lift the earth! The mechanical advantage on the dumbhead, well mine at least, comes from the long distance from the pedal to the pivot compared to the short distance from the pivot to the pinch point under the head. The foot moves a long way, the head much less, but with much more power. On the old frame horse the pedal just moved the same distance as at the pinch point at the top of the frame (as the pivot was in the middle) so no additional power was produced.

      Hope this helps,

      Richard

  2. “The foot moves a long way, the head much less, but with much more power.” – That is it.

    I think I’m going to retrofit my horse too, whenever I feel like it. I haven’t used it to much recently.

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