Edge joint, one inch birch ply?

[Cabinetman]

No I wouldn’t l be confident with three by one softwood, especially not at 800 mil high. My saw horses are 450 mil high and I used 1 1/2 x 2 1/2
Perhaps a sketch might be useful please Dave
Edit, 4 x 2 equals 8 square inches 3 x 1 is three that’s quite a reduction!

 

[pe2dave]

Sawhorse Plans | DIY Krenov Style Sawhorses | Philip Morley Which are based on others?

 

[Cabinetman]

Well maybe, if that’s what you want and it’s in solid timber, but it’s not my idea of a sawhorse.

 

[pe2dave]

That’s OK

 

[Deadeye]

I'm adding this thread to my forthcoming book of "why nice people can appear charmless on the internet"

 

[Cabinetman]

Well you’ve got me there Deadeye, and I thought I was being my normal smarmy self.
Always good to get a bystanders point of view, come on, lay it on the line, I can take it. Tell me, warts and all.

 

[MusicMan]

That design is quite like the one that MikeG wrote up on here a few months ago, though I thought his was better. Worth searching.

 

[AndyT]

It's been said before but not in this thread, so may I suggest that if you want to use plywood, you have a look at this design from @TheTiddles

https://www.ukworkshop.co.uk/threads/sore-hoarses-mkii-now-with-added-plans.44761/

 

[pe2dave]

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?

All I asked was how I might join two pieces of 1 inch ply. I noted, 50lb load max?

 

[profchris]

All I asked was how I might join two pieces of 1 inch ply. I noted, 50lb load max?

Well, I'd do it the easy (though ugly) way. Overlap the faces, glue them together, and run a couple of M6 coach bolts through to take the load.

 

[Woody2Shoes]

All I asked was how I might join two pieces of 1 inch ply. I noted, 50lb load max?

I think that with a leg of 800mm or so and a foot of 450mm or so, whether making them from solid timber or ply, I'd want some kind of bracket/gusset to strengthen the 'ankle' joint to resist racking forces. Why does the leg need a foot at all (assuming this is the leg of a saw horse/trestle-type thingy)?
Cheers, W2S

 

[pe2dave]

I think that with a leg of 800mm or so and a foot of 450mm or so, whether making them from solid timber or ply, I'd want some kind of bracket/gusset to strengthen the 'ankle' joint to resist racking forces. Why does the leg need a foot at all (assuming this is the leg of a saw horse/trestle-type thingy)?
Cheers, W2S

A 3" cross member takes care of that. Foot needed (as with people) to stop it / us tippling over? See the sketch in the link I posted?

 

[Austin Branson]

Sawhorse Plans | DIY Krenov Style Sawhorses | Philip Morley Which are based on others?

I’ve actually made a pair of these. I used oak as I had some. They work really well. If you’re going to make them from ply, I’m guessing you’re asking about joining the foot to the bottom of the leg. I used doweled mortice & tenons, but in ply a few biscuits should do it. You may need to beef up the two rails to resist racking.

 

[TheTiddles]

All I asked was how I might join two pieces of 1 inch ply. I noted, 50lb load max?

I think you have fallen into the trap that so many do, in that you think the question is easy as you don’t understand all the permutations and neither do we, so we ask.

If someone said “how do I join these two sheets of 2mm aluminium together?”, answers may vary from rivets and bolts through welding to adhesives and crimping, none or all of which may be appropriate depending on if those sheets were the stressed skin of a combat jet or a plant pot.

Aidan

 

[pe2dave]

I hope I've answered all the questions.

 

[Hornbeam]

The strength required from the joint will depend upon how you plan to use the horses. If using like a heavy duty saw horse then Custards design has a proven track record. You have said they are light duty and a max load of 50kg but it depends on how that load is applied and how it is cycled as to how stressed that joint will be.
Any form of joint that you cut will be removing material and potentially weakening both members. Using ply to form the joint either as the tenon or as a loose tenon means that only 50% of the fibres will be giving you any strength. I would also suggest that even at 3 inches wide dependant upon the racking you could get problems.
Simplest approach with either solid or with 1 inch ply would be dowels/domino with additional bracing. You could achieve this with external gussets of 6mm ply, gussets of 1inch ply which fit into the thickness of the frame (advantage of ply is that you should get a good joint just gluing in as you will get edge grain to edge grain) or achieve the same effect by tapering the uprights so it is 3 inches wide at the top and say 6 inches wide at the foot
Ian

 

[Woody2Shoes]

A 3" cross member takes care of that. Foot needed (as with people) to stop it / us tippling over? See the sketch in the link I posted?

I'm afraid I didn't find the sketch easy to interpret - I saw a horizontal piece (foot?) and a central vertical piece (leg?) coming vertically upwards from it and I thought the joint in question was the one between these two components.

 

[pe2dave]

The strength required from the joint will depend upon how you plan to use the horses. If using like a heavy duty saw horse then Custards design has a proven track record. You have said they are light duty and a max load of 50kg but it depends on how that load is applied and how it is cycled as to how stressed that joint will be.
Any form of joint that you cut will be removing material and potentially weakening both members. Using ply to form the joint either as the tenon or as a loose tenon means that only 50% of the fibres will be giving you any strength. I would also suggest that even at 3 inches wide dependant upon the racking you could get problems.
Simplest approach with either solid or with 1 inch ply would be dowels/domino with additional bracing. You could achieve this with external gussets of 6mm ply, gussets of 1inch ply which fit into the thickness of the frame (advantage of ply is that you should get a good joint just gluing in as you will get edge grain to edge grain) or achieve the same effect by tapering the uprights so it is 3 inches wide at the top and say 6 inches wide at the foot
Ian

No, I said 50 pounds, not Kg. In a largely stable usage.
I can't see how dominoes would be as close, strength wise, as a through tenon.
Tapered ply legs would be a good idea.
I have decided on solid wood, after this threads advice.

 

[pe2dave]

I'm afraid I didn't find the sketch easy to interpret - I saw a horizontal piece (foot?) and a central vertical piece (leg?) coming vertically upwards from it and I thought the joint in question was the one between these two components.

I referred to the cross piece some 10" up from the foot.

Please can we close this thread now, I've decided on a design.

 

[Woody2Shoes]

I referred to the cross piece some 10" up from the foot.

Please can we close this thread now, I've decided on a design.

I meant racking in the other axis. Good luck with whatever design you're going with. Cheers W2S