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Andy Dingley Andy Dingley is offline
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Default Sawhorse brackets

On 6 July, 14:24, T i m wrote:

a shaving horse.


Looked at Wikipedia and Wikicommons (for pictures)? There was an
article up there once (I wrote it), although some f*ckwit then tagged
it for deletion so I don't know if it's still there. There are also
the usual canon of green wood books (Abbot, Dunbar) and also the
Taunton workbench book has something on shave horses.

She'll need about five shave horses, then throw four of them away for
firewood and keep the one she likes. There's a bit of personal choice,
a bit of personal comfort about just which log is comfiest to sit on,
then a lot about the style of dog-head being appropriate for the
particular work you're doing.

What shape of dog head?

How many treadle levers, one or two?

Is the clamp on a raised sub-base above the bench? (German style)

What leverage ratio in the lever? (This is a good argument for a
raised sub-bench)


The easiest bench to build is a low bench with two side levers. These
are simplest but don't (IMHO) work too well. In particular, you're
working very low down with your drawknife and that's close to your
thighs.

It's also not really a bench, just a log - so you can make it out of
anything sittable, it doesn't have to be wide or flat.

So ... I though that even though these brackets may not be perfect I
feel the forces involved are generally between shaver and object
rather than object and ground etc?


Nope, they're racking forces in the top joints of those legs. Clamping
force is high too (esp. with a sub-bench), but as that's a pretty
rigid assembly, then it's not a problem.

Experts can use any old rubbish. Beginners aren't so good with a
drawknife so they push and pull the thing all over the place and
wrestle the bench around over the floor. It's quite common for someone
to use a shave horse happily for years, then run a weekend course with
it and have the thing rattling loose by the end of it!

It's traditional Windosr making to take a green log and shrink it over
some dry legs to make a long-lived tight leg tenon. Still not easy to
get right first time though, so if in doubt, brace the legs. If I were
making a demonutable, I'd probably make a single rail the whole length
of the bench and set it just above ground level. Maybe make the ends a
"hay rake" style (Y shaped) rather than a H shape. Then every joint is
boltable and it'll fit into a car.

Real fix though is to dump the Ka and accept her natural destiny of
either a Volvo estate or a Landie.