Mortise Bench

[dunbarhamlin]

Hey folks

Having chopped quite a few mortices recently, I'm of a mind to make a mortise bench.
There are a couple of brief glimpses of one in Master Kingshott's M/T video, but too little for my inexperienced eye to derive a plan from.

Are there any plans available online/in print?
Or (better yet) could I have thoughts on optimum dimensions (beam width/height etc) and construction?

Thanks
Steve

[mrgrimsdale]

What is a mortice bench? Do you mean a trestle or saw stool where you sit on the workpiece and mortice away between your knees, or was there more to the Kingshott thing? Also it'd depend on what size work you are doing as a rule.

cheers
Jacob

[dunbarhamlin]

Ahah - glimmers of light, thank you Jacob. Yes, the same thing, though made more like a pew, perhaps, with two ends, a stretcher and a heavy beam as the working surface bridled(?) into the ends.
So it'll be sense for me to make it the same height as my saw bench (which is a bit short to avoid unfortunate nips )

Guessing I'd need a good foot in front of me and the same behind my behind?
The working surface (unfortunately not seen in use) appears to be about 3" across by 5" deep (does that sound sensible?) Extra width is afforded over the ends.

Would it make sense to use some kind of housed bridle joint for these?

Would 7/8" be sensible for the ends, or should I go heavier?

Was considering a pegged through tenon for the stretcher - sensible?

sorry for the Qs - if I wasn't going to be hitting a sharp pointy thing while sat astride it, I'd just give it a go and learn from my bruised behind if/when I found I'd mucked up.

Cheers
Steve

[mrgrimsdale]

Hmm, so, like a saw stool or bench but with the top on edge instead of face? Was this purpose made do you think, or just a saw stool being used for the job? I can't see why you would need to make a special one different from the usual sort of thing.
What about a simple classic bench like a shaving horse but without the top stuff, i.e. just a plain bench. Heavy top, 8x3" or summat?
Mr Spanton's the man to ask, though he's probably too busy banging away on his keyboard abt marxist plots etc

cheers
Jacob

[dunbarhamlin]

Found the vid and pulled off a couple of pics - almost nothing like I described (no wine involved, honest!) - think my mind crossed it with a saw horse, sort of.



It was described as having been specifically for morticing (sat side saddle on the work)

[Alf]

That's interesting; different from what a mortise bench brings to my mind. Bit Japanese. Mostly the sort I've seen have resembled a regular saw horse, but with a wider top, although if memory serves sometimes you get specialist ones with straight legs that continue above the top surface to provide something to wedge the work against.

Cheers, Alf

[mrgrimsdale]

So you'd have 2 of them - one at each end of workpiece? Looks a bit odd to me. I wouldn't take too much notice of it. Why not a normal saw horse:



Pair of, or just one for small workpieces, or heavier design for bigger work

cheers
Jacob
PS And sitting side saddle sounds very uncomfortable if not impractical, as you'd have to twist around.
Doing a mortice by hand you need to stand at the end of a bench with the workpiece going away. Normal bench is a bit too high so I stand on a box. Or on saw horses etc sit astride it with the mortice between your knees.

[andy king]

I would say the pic posted by dunbarhamlin is the better design for hand morticing.
Any striking force is transferred directly down the leg to the gound for maximum cutting performance, much the same as striking over the leg at the workbench - taught as good practice when I was an apprentice.
On Jacobs saw horse, despite the gussets to stop the leg splaying, any direct striking force is still going to disapate down, and try and force the legs, so the full striking impetus is lost.
dunbarhamlin's horse is much the same as Jacob's you can use it singularly and sit on the work, (again, taught as good practice to sit on the work if hold downs weren't available at college when I were a lad...) or as pairs for bigger stuff, and you can still have the mortice directly over the leg and sit on it when striking.

Andy

PS. Sitting 'sidesaddle' or on top of the work allows you to sight perfectly along the work to ensure the chisel is upright.
On longer work or on stuff clamped along the length of the bench, you need to lean in slightly to sight it, which could lead to minor parallax error and chopping at a slight angle.

[mrspanton]

May 27, 2008 17:19:13 GMT mrgrimsdale said:

Hmm, so, like a saw stool or bench but with the top on edge instead of face? Was this purpose made do you think, or just a saw stool being used for the job? I can't see why you would need to make a special one different from the usual sort of thing.
What about a simple classic bench like a shaving horse but without the top stuff, i.e. just a plain bench. Heavy top, 8x3" or summat?
Mr Spanton's the man to ask, though he's probably too busy banging away on his keyboard abt marxist plots etc

fookin marxists ;D

That video still is exactly like the mortice bench in George ellise's carpentery book. I believe they used pair's? They were low with legs and top beam bridled together. They chopped part of the mortice with a chisle but finished it with a wooden bolster aparently to save time
Sitting directly above and in line rather than slightly to one side as you do at a bench, I think would be more comfortable (I've not used any of these up to now). Lift your ar*e, move rail along a bit, replant ar*e, continue-no wasting time opening and shutting the vice or altering your hold fast's/puppy dogs or whatever.

[mrgrimsdale]

May 30, 2008 22:30:14 GMT mrspanton said:

snip
fookin marxists ;D

That video still is exactly like the mortice bench in George ellise's carpentery book. I believe they used pair's? They were low with legs and top beam bridled together. They chopped part of the mortice with a chisle but finished it with a wooden bolster aparently to save time
Sitting directly above and in line rather than slightly to one side as you do at a bench, I think would be more comfortable (I've not used any of these up to now). Lift your ar*e, move rail along a bit, replant ar*e, continue-no wasting time opening and shutting the vice or altering your hold fast's/puppy dogs or whatever.

Right so it is I never noticed it before. Good these old books, no doubt about it.
3 bits of wood; 1 top rail and 2 legs, with a v cut out to give 4 simple feet. No braces or stretchers apparently. The only big difference is that Ellis has the sides of the bridle joint extending above the beam surface, and mentions wedging the workpiece here. But if you did that often you'd split the one piece leg Ida thought, so praps ignore that - the whole point is to be able to move it about easily as Jonathan describes.
Height? Comfortable sitting astride height say 18/20 inches, less thickness of typical workpiece.
The wooden "bolster" or loose tenon (hardwood - permanent bit of kit, one for each tenon size) is what I was taught so that's a bit I did know.
The point being that you just blast the mortice through with the chisel ALWAYS dead vertical, no levering etc. Waste either flies out or gets pushed out by the bolster - or by the tenon when you knock it all up.

cheers
Jacob
PS pair of padded cycle shorts might be good idea

[dunbarhamlin]

;D thanks chaps. Must try the bolster wheeze.
Think lurid lycra might interfere with the Fen Shui - would lederhosen do the job?