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Critticle Lumber shortage- BDA Blues
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May 7, 2021 - 11:07 am
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I was getting ready to build 8 BDA boxes. But there is only 1 sheet of 1″ 4’x8′ MDF in my county or any of the surounding counties.
and the main distributor has no idea when they will get anymore product, it may be several months.

So now I am working on an alternative material for the box construction.

Since this is a material density issue
The densest material I can think of that is still in abundance is Hardybacker concrete board, which is around 6000 PSI.

This product only comes in 1/4″ and 1/2″ so I am figuring out a material to combine the hardy backer with.

Using a high strength epoxy to glue 1/4″ hardy backer to perhaps 3/4 plywood, with the hardy backer on the inside. This will be an in wall build so I don’t care what the box looks like on the out side, so long as it is dimensionally correct.

The hardest part of this is creating the channels for the resonate panels and the peg board to slide into. I may just cut the hardy backer with a tile saw blade into sections matching the spacing between the panels creating the proper gap.

This is all in the hypothetical stage right now hoping for some kind of lumber miracle in the mean time.

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May 9, 2021 - 3:29 pm
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You can use two sheets of 1/2″ MDF to make the BDA cabinet. If you want extra performance increase the rear “wall” by 100 % and use mass loaded vinyl between the sheets of MDF.

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May 9, 2021 - 6:24 pm
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Dennis Foley said
You can use two sheets of 1/2″ MDF to make the BDA cabinet. If you want extra performance increase the rear “wall” by 100 % and use mass loaded vinyl between the sheets of MDF.Β Β 

I was just thinking about using MLV as part of the equation.

A couple of questions. Have you ever tried using MLV between the charcoal and the back wall of the cabinet, suspended an inch off the back wall? Not sure if this would diminish the Q of the box?

Titebond 3 is a 4000 psi wood glue, can I use that to glue half inch MDF sheets together or do you have a perfered glue you have tested?

Thanks

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May 12, 2021 - 7:04 am
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Any standard construction adhesive will work. Remember it is all about density.

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May 22, 2021 - 10:43 pm
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Dennis Foley said
Any standard construction adhesive will work. Remember it is all about density.Β Β 

I decided to go with 3/4 inch MDF plus a layer of 1/2 MDF to make the box denser

The only thing I am having trouble finding now is the 3/8″ that’s pretty scarce.

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