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I am working on a small project to build something like this https://www.amazon.com/dp/B07BBL7W46 and the part where I am stuck is how to attach a 1/4". thick plywood to two 15/32" thick plywoods at 90°.

Here are the pictures to give full idea on what I am talking about: first second third

My initial approach was to glue it but it will become permanent. I want to be able to disassemble for storing purposes and assemble when there is a need.

EDIT: Purpose of attaching this 1/4" plywood is to be able to just support any photo frame leaning on it and not really load bearing or anything like that. Something like this: 4

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  • Hi, this can be done with threaded inserts + bolts but any hole near edge of 1/4" plywood will be weak. Maybe best to use magnets but could be $$$ unless you buy from China.
    – Volfram K
    Feb 16 at 6:55
  • Is the purpose of the side panel to hide what's behind the table or is it to add structural strength to the table. If it's just to hide things, then @VolframK's suggestion will work. If it's the latter, that won't help at all.
    – FreeMan
    Feb 16 at 14:34
  • This is a trickier problem than it might at first appear, because of the relative weakness of 1/4" ply of the type seen in your photos. It's OK if you use it and leave it alone, but it will soon begin to show wear in any application where you need to repeatedly run screws/bolts through it (although if it's the back maybe this doesn't matter too much?) A more long-lasting solution would be to glue something to the inside face, and then rely on that to hold the sheet up. If you go with magnets as suggested this would be a steel strip epoxied on, for threaded inserts it would be a strip of wood.
    – Graphus
    Feb 16 at 15:15
  • @VolframK I added more details about the purpose of adding this 1/4" ply. Magnet approach sounds like a good one but I am confused as how to add magnets to 15/32" thick plywood? Do I need to find magnet with radius less than 15/32" and stick in it? Also, what radius magnet I need on the 1/4" ply? Thanks!
    – javanoob
    Feb 16 at 20:11

3 Answers 3

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Simple, quick and dirty solution:

Screw or glue a piece of wood to the bottom of each of the half-inch sheets. Should be somewhere around 1" by 1" (or larger) and across the length of the sheet. Now you can use threaded inserts or throughbolts and a nut to attach the 1/4" sheet to these blocks.

This way you don't have to screw into the narrow side of a plywood sheet which can be tricky or simply delaminate the plys if you are not carefull. Also, like Volfram K said, holes near the edge of the 1/4" will be weak. This will give you some space to move the holes inwards.

The lower "block" won't be visible, the upper one a little bit (depending on size and perspective). But since I'm guessing the whole thing will be painted anyways, you can just incorporate it into the design.

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  • Shouldn't cleats be attached to the 1/4" ply, so the thin plywood isn't being asked to do any holding on its own? And 1" square may be overkill too, 1/2" could do it especially if made from hardwood.
    – Graphus
    Feb 16 at 14:39
  • It looks like the 1/4" is resting on the bottom, so it wouldn't need to support any weight, just not tip over. Otherwise yes, some more support on the back might be in order. Also I'm not good with imperial. Less than 1" sq will probably do as well. But that depends on OPs skill, wood and strength requirements I'd say.
    – Max
    Feb 16 at 15:14
  • "I'm not good with imperial" I'm a metric head as well. I'll translate: 12-13mm square. "depends on OPs skill, wood and strength requirements I'd say" Yup, lots of unknowns here.
    – Graphus
    Feb 16 at 15:17
  • erm... @Graphus 1" = 25.4mm
    – FreeMan
    Feb 16 at 17:32
  • @FreeMan, yassup, and half of that is 12.7mm (or 12-13mm where it doesn't need to be exact).
    – Graphus
    Feb 17 at 5:04
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Magnet approach sounds like a good one but I am confused as how to add magnets to 15/32" thick plywood? Do I need to find magnet with radius less than 15/32" and stick in it?

If you go with magnet solution find strong magnets in suitable size, drill holes in plywood and glue magnets in holes with CA or epoxy.

  • 15/32" = 12mm (11.9) so 8mm ok size.
  • 8mm magnets very common size, so cheap.
  • 5/16" close match to 8mm so no need for metric bit set.

Also, what radius magnet I need on the 1/4" ply?

Magnets only mounted in thick plywood so no holes necessary in thinner plywood. Also do not need to worry about polarity!

Epoxy L bracket to plywood, or glue thin pieces of wood to plywood and epoxy steel strip on top.

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If the "finial" looking thing at the left of the first picture aligns with the column, then you could cut a couple of 1/4" wide rabbets in the thicker plywood, insert the edges of the 1/4 plywood in the grooves, then pull the upper and lower pieces together. Assuming the back piece will be against a wall, the fact that there is an overlap of the upper and lower pieces shouldn't be a problem.

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