Edge joint, one inch birch ply?

[pe2dave]

3x1 inch ply, joined into T shape.
Timber, mortice and tenon.
Suggestions please, how would you join the ply? Downward stress, length of the body, into the cross member,
with lesser stress diagonal. E.g. as a leg and foot structure.

 

[DBT85]

I'm really sorry Dave, I cannot grasp what you are attempting.

 

[pe2dave]

Try again:
Vertical leg, about 800mm. Horizontal foot, about 450mm
Were it 3x1 softwood I’d use a mortise and tenon.
Is it feasible to use 1inch ply for the same purpose?
If so, how to join(reliably) to pieces of ply?

Is that clearer @DBT85.

 

[thomashenry]

why not mortise and tenon?

 

[MusicMan]

This is theoretical as I have never done it. The trouble with an M&T in ply is that about half of the tenon will be cross-grain material, which has little strength, so the tenon will be much weaker than in solid timber.

If I had a domino machine this would be my choice, alternatively loose tenons, alternatively several dowels. In each case you have long grain either side of the joint.

 

[Cabinetman]

Well it is a bit clearer Dave, but is it this way or that way

 

[Cabinetman]

Sorry that didn’t come out very well did it! Basically are you joining them edge to edge your flat ways on. Ian
Edit or a mixture of the two?

 

[spb]

I'd definitely use loose tenons or dowels there.

 

[pe2dave]

Sorry that didn’t come out very well did it! Basically are you joining them edge to edge your flat ways on. Ian
Edit or a mixture of the two?

From my interpretation of your drawing (sketch) Edge to edge? I.e. plane of leg same as plane of foot?
A loose tenon does make sense - into leg and foot.
Perhaps another piece of ply? 6 or 9mm?
Whatever I can find in the way of a bit!

Thank you.

 

[custard]

Pop a Domino in it and move on!

 

[pe2dave]

Pop a Domino in it and move on!

You buy me the Domino and I will custard ;-)

 

[Cabinetman]

T halving joint? But it depends on what it’s for really.

 

[pe2dave]

T halving joint? But it depends on what it’s for really.

Is this different from a loose tongue please?
Use: One leg of a sawhorse, say 50lbs max load.

 

[DBT85]

You buy me the Domino and I will custard ;-)

If you have a router and a straight bit you can make a mortice in both for a loose tenon

 

[pe2dave]

If you have a router and a straight bit you can make a mortice in both for a loose tenon

For an edge joint, I’d rather use a morticing bit... Depth? A consideration though tks.

 

[Cabinetman]

Dave, I’m sorry but joining 1 inch plywood like that and expecting it to survive as a leg on a sawhorse, well you’re on a hiding to nothing I’m sorry, just won’t work. Even if you had cut T-joint out of a solid sheet of 1 inch ply it would still not be very stable. A 3 x 1 section of ply 800 mm long will be pretty flexible.

 

[DBT85]

oh this is for a saw horse? I think I'd be laminating at least 2 lengths for both the leg and the foot as a minimum. More likely 3.

Are you attempting this out of necessity or just an experiment?

 

[pe2dave]

Noted @Cabinetman - Yet I’d be confident with 3x1 softwood? Not sure I follow your logic?

 

[custard]

Cabinetman's right, for a saw horse beefy is always best. Here are my saw horses,

Design as if you'll be parking a locomotive on them...then add a bit!

 

[pe2dave]

I have a pair made from 4 x2. Now I want slimmer, lighter ones.
From this thread, I’ll stick with3x1 softwood, thanks people.