Screws in Cabinets: Yay or Nay?

[gassit]

Hi,

Assembling a cabinet now and I've noticed that one of the glued bracing panels has a hairline gap along part of its length where it doesn't quite fit flush with the cabinet wall.

There seems to be a general reluctance to use any screws in speaker cabinets and to go for a "glue-only" approach when it comes to cabinet construction.

Would it be okay to put a drywall screw in the bracing panel so it contacts the cabinet wall and thus reduces a possible source of vibration at the hairline gap?

Also, to eliminate any possibility of the screw eventually becoming loose, should glue be injected in to the screw hole before the screw is screwed in good and tight?

Thanks for any suggestions!

 

[DrBoar]

I would rather fill out that hairline gap. Unglued screws just hold things in place until the glue sets. Glued screws asymetrically placed could be wieved as breaking up symmetries and thus spreading resonance patterns.

 

[gassit]

Hello DrBoar,

Thanks for your reply.

How would you suggest I fill out the gap?

 

[Scottmoose]

It's not much of a bracing panel if it's not making contact with the box walls.

 

[cogitech]

I would use construction adhesive instead of carpenter's glue on that particular joint. Put a fairly thick bead on. It will easily fill the gap and will remain very slightly pliable indefinitely, which will provide the desired damping and resist cracking/rattling.

 

[DUG]

Mix sawdust with glue. (mix very well)

Fill the gap.

Use tape to hold the mix in place until the glue dries.

Remove tape.

 

[doubtingthomas]

Car body filler.

 

[prairieboy]

Screws are simply clamps in a different shape.
Use good epoxy (West Systems, SystemThree) with a filler and 'shove' into into the gap, and along the seam. Give it 24 hours and it will never move.

 

[nigelwright7557]

I have never glued panels on my speaker boxes.
I always use 2 by 2 bracing, screws every few inches and have never had any problems.
Clearly if you want a wood finish then screws are a big no no.
I have always covered my boxes in thin carpet which is hard wearing for mobile use.

 

[Cal Weldon]

I would use construction adhesive

First prize goes to cogitech.

 

[cogitech]

First prize goes to cogitech.

Yay!

My second choice (or first choice if I had some lying around) would be exterior acrylic caulking.

 

[Cal Weldon]

Methinks it wouldn't couple well enough.

 

[chrisb]

It's not always possible to get deadly tight fit on bracing panels - less and .5mm or so gap isn't enough to get exercised about. As has been suggested, use a good construction adhesive (PL400) and screws - but not drywall screws - they're notorious for breaking.

I'd suggest Robertson brand (square drive) or equivalent Lo-Root wood screws with nibs. Be sure to drill appropriate size pilot holes or risk splitting material on edge grain - not a good thing.

An externally hosted image should be here but it was not working when we last tested it.

 

[DUG]

First prize goes to cogitech.

LOL

I really did.

 

[cogitech]

Methinks it wouldn't couple well enough.

The stuff I am thinking of binds to stuff like tar, firms up nicely into a stiff rubbery substance which is designed to last 30 years in various weather conditions. I wouldn't hesitate to use it in a speaker.

 

[Cal Weldon]

Nor would I but I would use it for air sealing not for bonding. Rubbery isn't necessarily good if you are trying the raise the resonant frequency of the panel. Construction adhesive or sub floor glue is good.

DUG get second prize because he is resourceful and frugal.

 

[cogitech]

Nor would I but I would use it for air sealing not for bonding. Rubbery isn't necessarily good if you are trying the raise the resonant frequency of the panel. Construction adhesive or sub floor glue is good.

DUG get second prize because he is resourceful and frugal.

I think the (very firm) rubberiness (sp?) would help to eliminate resonant frequency (rather than raise it). It would work like a shock absorber of sorts, as it is pliable but moves incredibly slowly. Not anything like silicone, which is "bouncy". That would be a bad choice, as it doesn't adhere to wood very well, either.

 

[chrisb]

Nor would I but I would use it for air sealing not for bonding. Rubbery isn't necessarily good if you are trying the raise the resonant frequency of the panel. Construction adhesive or sub floor glue is good.

DUG get second prize because he is resourceful and frugal.

I'd still use screws in combination with the adhesive, and leave them in place.

 

[chrisb]

The stuff I am thinking of binds to stuff like tar, firms up nicely into a stiff rubbery substance which is designed to last 30 years in various weather conditions. I wouldn't hesitate to use it in a speaker.

SikaFlex?

 

[cogitech]

SikaFlex?

Can't remember the exact product name right now, but I think I still have a tube at home.

It was either DAP Dynaflex 230 or DAP Alex Ultra 230...

I think an even better choice would be DAP Premium Polyurethane Adhesive Sealant (which is virtually the same thing as SikaFlex, AFAIK).