Simple joint advice needed

[Digizz]

Hi,

Need some advice on a simple joint. The joint is the top corner frame - This frame will be hidden inside aquarium cabinet. stock size is 50mm x 40mm (not square due to equipment sizes). I was going to use M+T but if I can get away with something quicker but still strong, will use that instead. Wanted the rail long and across the uprights for extra strength as there is a long opening for cupboard doors at the front which needs maximum strength.

How would you do it?

Also, need some way of fixing frame inside cabinet - was just going to glue to the inside as the side/front/back panels are biscuited together and are very strong (already done this bit). I guess they dont even need that?

 

[Aragorn]

Quickest thing I can think of would be pocket screw joints.
Put the pockets on the outside so that they are hidden by the faceframe.
Can't get much quicker than that, and it's very strong when the glue's dried.
Otherwise, I would use M&Ts.

HTH

 

[Digizz]

Thanks - do you need a pocket screw jig to do this right?

Are they as strong/stonger/weaker than M+T and how much?

 

[Aragorn]

Yes - best to use a pocket hole jig.
Doesn't need to be a pricey one for a one-off job like this. Something like this is fine, although I know I've seen cheaper elsewhere.
I'm not the one to ask about joint strength. Personally I think the whole thing's a bit of a myth anyway. Whenever a joint is subjected to that much force to break a well made joint, I'd have thought the wood would fail first. But what do I know?
A little while ago, I had to undo a pocket screw joint I'd made about 4-5 minutes previously. I took the screws out, expecting to be able to pull the joint apart. Could I move it? In the end I was smashing it with a large hammer and it still held fast. Had to saw it off in the end and replace the rail.

 

[jasonB]

Having followed your other posts, using pocket screws will mean all the load on the side members is being carried by the screws.

A halving joint may be better as the upright corner post will then be supporting the long AND short rail and transfering the load straight into the frame.

To form the joint cut half the thickness of the long rail away for a length of 40mm and make a corresponding cut in the short rail, hope that makes sence.

Jason

 

[Chris Knight]

Digizz,

Here's a classic
https://www.ukworkshop.co.uk/forums/view ... inese+tony

 

[Digizz]

Having followed your other posts, using pocket screws will mean all the load on the side members is being carried by the screws.

A halving joint may be better as the upright corner post will then be supporting the long AND short rail and transfering the load straight into the frame.

To form the joint cut half the thickness of the long rail away for a length of 40mm and make a corresponding cut in the short rail, hope that makes sence.

Jason

Something like this:

I'm not sure how to fix it in place - don't have any dowels but was thinking of just gluing it all in place - bad?

 

[Noel]

Glue will work, but how well? You've only got one surface without end grain. Better with one or two dowels straight down.

 

[Digizz]

Glue will work, but how well? You've only got one surface without end grain. Better with one or two dowels straight down.

Does it matter though? - isn't the glue just keeping the rails in place as all the force is downwards (unless someone gives it a really hard shove sideways)?

 

[Anonymous]

I would also reccomend a pocket hole joint if you want a very cheap pocket hole jig try this link about half way down their is one for less than £4 and the postage is free and next day. http://www.toolstation.com/shop/HandToo ... /d10/sd150
Never used one so i don't know what they are like.
Cheers,
Derek.

 

[Noel]

Mostly downward pressure but there'll be some lateral force too, especially if the rails are supporting, or part supporting, the load of the tank. Dowels, or some other additional method, would assist in enhancing the overall rigidity of the structure.

 

[jasonB]

Thats the type of joint I was talking about, I suppose you could just use a long screw doen into a pilot hole in the top of the post to stop splitting, Won't give a great deal of strength but will help with location.

What glue are you using by the way :?: not too sure how well the "waterproof" ones will hold out in a warm salty enviroment.

Jason