Thread: Ply boxes

Originally Posted by mch

Would it be ok to attach the aluminium moulding to the plywood using smallish screws that go into the plywood edge? Will this split the ply? If so, is there a better way to do this?

Yes, it will tend to split the ply. Better to place the screws into the face. Use countersunk screws so they don't protrude into the air space. Also, although somewhat tedious, use screws long enough to provide substantial bite into the wood, and grind flush on the other side.

Cheers,
Joe

Thanks Joe,

Just to clarify, I will be attaching the L-shaped aluminium moulding to the ply, and the screw head will be tightening against the aluminium surface, not the ply surface.

If you can imagine a box made of 5 pieces of 400 x 400 x 12 ply, and an L-shaped strip of moulding attached to each edge so that the corners of the box are recessed and the ply pieces aren't actually touching each other - that is what I'm trying to do.

Is there any way of attaching aluminium moulding to a ply edge (not the face) without splitting it? Expanding bolts? Screws inserted into rubber sleeves?

Cheers!

Matt

Is this what you mean?

YES!! Thank you.

I was thinking of this design so that we are screwing into the face of the ply.

Watcha reckon?

I have made it 400mm inside, Is that what is desired? Or 400mm outside?

I hope you can all view this in Sketchup OK.

There would be 4 vertical bits of aluminium ally with one compound mitre.

And the 4 bottom ones with both ends mitred.

I would be happy with the looks of them, alas as what they would cost to make?

Hope this helps and does not confuse!

Tankstand, by mitred you mean that the aluminium is recessed 12mm into the ply using a router so that it is flush with the surface? Because I can't really have it sticking out at the corners (the boxes will stack on top of each other, then there will be books laid flat over the top layer).

Originally Posted by mch

Tankstand, by mitred you mean that the aluminium is recessed 12mm into the ply using a router so that it is flush with the surface? Because I can't really have it sticking out at the corners (the boxes will stack on top of each other, then there will be books laid flat over the top layer).

Hi,

Yes the angle will be flush with the ply.

The thickness of the angle say 3mm is rebated into the ply and as wide as is needed.

By Mitred I mean that the corners butt up against each other at the bottom, I have only drawn one mitred piece of ally. It might look like it is sticking out at the bottom, but two others would come up and join the one shown. All having 45 degree angles.

I just drew it this way with that void down the corners so that it is made up of 5 pieces of ply all the same size. The base and two sides could be made wider to fill that void also allowing for some glue and nails before covering the corners with angle.

If you have Sketchup you can roll this model around and get a better idea of what it would look like.

Just an idea.

Thanks m8, now that you've explained it I really like your design. I might do a trial run to see how long it takes to make one, and see if it's an easy and quick enough job. I have to make 100 of them, so they need to be pretty quick to knock together.

Oh, and I said 12mm rebate before - yeh, it would be more like 3mm.

Oops! I misunderstood the relation of the angles to the plywood. I was thinking more in line with Tankstand's arrangement.

To attach the angle like DJ shows, I'd drill holes through the plywood at the screw locations, and glue hardwood dowels cut flush with the surface. Dowel diameter about the thickness of the plywood, and placed two diameters from the edge. This is the strongest way to connect anything to end grain, BTW.

Countersink the screws in the angles, and for added finesse, align the screw slots with the length of the angle.

Cheers,
Joe

MCH
I'd use a different design all in solid wood and ply

Dimensions would be about 400 x 400 x 400 -- the about is very important as you should aim to maximise yield from each sheet of ply.

I'd go for 395 x 395 ply squares -- a single sheet should yield 18 pieces, so you'll need a total of 28 sheets
Buy from a supplier who has a full sized panel saw and will cut the sheets into the pieces you need.

I'd use solid timber for the corners as it's less likely to scratch than Al angle and glue rather than screws
Doing it this way you can probably build the boxes out of 9mm ply rather than 12mm meaning they are cheaper and lighter.

My drawing program is currently down so it might be a while before I can post a picture.

Build yourself a couple of jigs so getting the boxes square as you assemble them will be easy

mch
Options for joining ply wood include
lock mitres


splines -- link Joining box corners

If it was me I would be having a talk to one of the aluminium companies who market extrusions, they may have a extrusion in their standard range for the exhibition, shopfitting and or the demountable partition trade.
By my calculations there would be approx 600 to 700 metres of extrusions required, if so then it may be worth investigating having a special die made to run a extrusion to your particular requirements, if there is any chance of a repeat order they would jump at the chance. You could also market the extrusions to the trade as someone else may be interested in the profile.
I am not sure what a small die for a extrusion profile that you would require, in the past ( 10years ago) they would have cost $500 to $600 .
If you explain what you want they most likely will design a profile to suite you.
I visialise a angle profile with some type of a tail incorporated into centre of the rear face which could slot into a groove in the edge of the plywood. The profiles would be cut with 3 way mitres to the corners and the trim would then be knocked into the edges of the plywood pieces. Another possibility is a plastic
( vinyl) extrusion , something like they use on Hardifex fibre cement sheet fixing.
Contact Alsec ( Aluminium System Specialists) is one company that comes to mind for aluminium extrusions.
Best of luck
Regards
Malcolm Eaton

Originally Posted by Malcolm Eaton

If it was me I would be having a talk to one of the aluminium companies who market extrusions, they may have a extrusion in their standard range for the exhibition, shopfitting and or the demountable partition trade.
By my calculations there would be approx 600 to 700 metres of extrusions required, if so then it may be worth investigating having a special die made to run a extrusion to your particular requirements, if there is any chance of a repeat order they would jump at the chance. You could also market the extrusions to the trade as someone else may be interested in the profile.
I am not sure what a small die for a extrusion profile that you would require, in the past ( 10years ago) they would have cost $500 to $600 .
If you explain what you want they most likely will design a profile to suite you.
I visialise a angle profile with some type of a tail incorporated into centre of the rear face which could slot into a groove in the edge of the plywood. The profiles would be cut with 3 way mitres to the corners and the trim would then be knocked into the edges of the plywood pieces. Another possibility is a plastic
( vinyl) extrusion , something like they use on Hardifex fibre cement sheet fixing.
Contact Alsec ( Aluminium System Specialists) is one company that comes to mind for aluminium extrusions.
Best of luck
Regards
Malcolm Eaton

Check "Sapphire Aluminium Industries" web site they may have something available Sapphire Alumnium
Mac

Thanks, all very helpful advice.

@ Ian - attaching the timber edging to the ply would be done using dowel + glue, not just glue yeh? And I get what you mean about using pieces just under 400mm to take into account the width of the cut itself.

@ Malcolm, yes, I was actually considering this too, but am a bit worried it might end up costing a fortune. Will follow it up. BTW, is it possible to cut a groove into 12mm ply while maintaining its stability or would I need to go for thicker ply?