Hey guys,

Ive almost finished building my sub enclosures and Im not sure about internal bracing.

My box design is as below.

I was thinking of putting x8 90degree triangular braces on the edges inside the box using the leftover 18mm MDF, each triangle 3" x 3".

Do you think I really need to do this but? The outside dimensions are 16inches high by 17.7 inches wide to give a volume of 0.85 cubic feet.

Is it still worth doing this much bracing for such a small enclosure using 18mm MDF ?

Cheers

Note- the odd shape is so it will fit in a ute

a box that size shouldnt need internal bracing ....

im pretty sure theres a tutorial about box bracing somewhere in the tutorial forum.. (from memory)

bracing can only make your box stronger, the only downside is they eat into your volume. Seeing as you've gone with sealed you can probably give or take a bit on volume.

In your case, if you've built the box well, ie: square cuts, pva, screws, you'd prolly get away with no bracing. If in doubt, place them in the middle of each panel.
Well worth the extra 5min work for peace of mind.

bracing can only make your box stronger, the only downside is they eat into your volume. Seeing as you've gone with sealed you can probably give or take a bit on volume.

In your case, if you've built the box well, ie: square cuts, pva, screws, you'd prolly get away with no bracing. If in doubt, place them in the middle of each panel.
Well worth the extra 5min work for peace of mind.

In terms of volume, Ive actually taken the braces into account, so thats not a problem.

I was going to use Liquid Nails instead PVA, only because Ive already bought it, but everything else is there... square cuts, deep screws etc.

A couple of years ago i was smashing up some old boxes with a sledgie (as you do) I removed all the screws and swung away. The boxes with liquid nails would break at the joins whereas the joins where PVA was used would hold out before the mdf let go. impressive.

That said, IMO, i think we get a bit carried away with construction. I doubt you'd notice the diff between l/n and PVA. SPL'n is another matter though...

Liquid Nails is crappy. It does the job but its crappy. If you buy some thats been sitting on the shelf for a while its even worse. RVA glue or good silicone is only a few dollars more anyway.

Is Aquadhere the same stuff?

I got heaps of this in the shed

yeah, aquadhere is pva, if im not mistaken.

Consider fibreglass. Just put the resin down, mat, resin etc. Easy, quick, and can be as messy as you want on the inside of a box.