Thread: Suggest Ply Wood for Project

3.6mm ply would bend to your requirements, in either specie, quite easily.

I'm not sure how you intend to keep the ply bent to the design curve

personally I'd laminate the curve using 5 or 7 plies of solid timber -- the finished thickness would be around 20mm
lamination would give you a consistent bend on all the slats
solid timber will be easier to finish than ply. The ply might have very thin face veneers and a less than ideal rear face

if you go with ply try and get it cut on a panel saw


also, those feet look a little short for the height of the screens

As the frames have crossrails the uprights would remain in position. The ply would need to be well attached to the uprights. A temporary, removable upright, equal in thickness to the required bend, would be slipped down the centre and extracted after all the ply strips had been fixed in place.
Well, thats the theory anyway.

Hi Rusty
can I suggest that if you are going down teh ply route, you make each slat from two thicknesses of ply glued together in a former. If you do so the slats should retain their bend
I suspect that if you use single piece slats, the spring back will readily pop the slats off the uprights.

Thanks for everyone's help. I am not worried what the rear side of the screens will look like - they will be facing away from front of stage. However I certainly wouldn't want the panels to tear and fly off if the tension caused by the bending is too high . There isnt a large curve on these panels - only about 200mm over the distance of 2400mm, so if it was ply, I could form them first.

An alternative to ply - and I hope I am not swearing by saying this Has anyone used the Laminex timber veneer range? Something like this attached to 3mm craftwood may also work? (Laminex - Products – Create your perfect space)

Thanks again

Hi Ian,
That is the reason why I suggested the ply must be well fixed to the uprights. Glue and screw would be strong enough to withstand pressures exerted by 3.6mm ply with a 200mm curve. If there were no cross rails then a formed shape would definitly be required.

Also - regarding the feet, as mentioned by Ian - I am thinking of changing the feet to be simply two 300 x 300 heavy duty steel square brackets for each leg rather than wood for extra strength and weight at the bottom. (Something like the attached photo). These panels are 2.4m high top to bottom. The should be weighted evenly across the center axis. Do you think this would work or would the legs need to be longer or weighted. Thanks

It very much depends on what forces the panels are going to have to withstand. Will they be subjected to wind, bumping etc. I assume they cant be fixed into position. Another option, if the panels are going to be side by side they could be set up in a sawtooth configuration so one helps support the other.

Originally Posted by tyes

Thanks for everyone's help. I am not worried what the rear side of the screens will look like - they will be facing away from front of stage. However I certainly wouldn't want the panels to tear and fly off if the tension caused by the bending is too high . There isnt a large curve on these panels - only about 200mm over the distance of 2400mm, so if it was ply, I could form them first.

An alternative to ply - and I hope I am not swearing by saying this Has anyone used the Laminex timber veneer range? Something like this attached to 3mm craftwood may also work? (Laminex - Products – Create your perfect space)

Thanks again

Tyes, you will need to finish the rear and edges of your slats to minimise the possibility that the slats will warp, a risk given that they are thin and attached only at their ends

Laminex is much harder to use compared to ply or timber
cutting the sort of slats you want would typically involve using a panel saw and cutting over size
the laminate would need to attached to the ply/mdf substrate using contact adhesive -- which can be tricky for beginners
the glued up slats would need to be trimmed

Tyes
I haven't done the calcs, but at 2.4m high, around 2.4 long, with a 200mm bow in the centre, I think your feet will need to be around 500, maybe 600mm long.
Please note I've done no calcs, the actual foot length may need to be more than 600

also, I suspect that steel angle will be "wobbly" in service

also, the steel is likely to scratch the floor the panels are to stand on

Originally Posted by tyes

snip
However I certainly wouldn't want the panels to tear and fly off if the tension caused by the bending is too high . There isnt a large curve on these panels - only about 200mm over the distance of 2400mm, so if it was ply, I could form them first.

because the panels will be curved, and the posts square (or rectangular) it would be best if the uprights could be champhered to the angle which will allow the slats to sit flat across the face of the upright
the angle I calculate is about 72° -- but my trigonometry is pretty rusty