Screwing the sub into a sealed box...

palvaro

CarAudio.com Newbie
This is a stupid question but I just wanted to make sure as I've read conflicting information. I built a sealed box for my infinity Kappa sub. I am wired up and ready to finish up by screwing in the sub. I have 1" screws that came with the sub but I used 3/4" mdf for the box. Is it ok to use the 1" screws even though they will pierce through the mdf or should I go get slightly smaller screws that won't go all the way through?

I've read some installers talk about how it's not an issue and to just pilot and screw through while others have said that it will create an issue for the sealed box as air could escape through the screw holes possible resulting in a whistle. Any thoughts or help with this would be greatly appreciated as it's my first box and I'd rather not screw it up on the final step. Thanks
 
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1 inch screws should be fine. With the lip of the subwoofer taken into account, they would barely go all the way through. If you remove the screws and sub a few times you might get some whistle. Nothing that a few toothpicks jammed down into the screw holes before putting new screws in wouldn’t fix anyway.
 
I've always used screws long enough to go through and I've had primarily sealed boxes...never had any issue with air leaking from the screws...if you drill a pilot hole just use a bit that's smaller diameter than your screws and it should be fine...
 
I wouldn't go 1" personally. I would either go 3/4" after the speaker mounting thickness you shouldn't pierce, or go 1 1/2" or more. Not because of piercing the hole for a seal, but because if you do pierce it, I wouldn't want to barely pierce it where it is more likely to leave a weak point in the MDF. I could be completely wrong, but piercing it just barely seems like you are making it more likely to chip or flake. I COULD BE WRONG: but mdf is glued and pressed chips as it is. Just barely piercing it seems like the probable way for it to get worse. OR at least know how to pre-drill the holes for the correct size based on the screw's shank size.


If you might take it out several times, you might want to consider T-nuts. They come in all sizes, but you would drill the hole big enough for that center section to fit in, and you tighten them down to pull them into, the underside of the wood. This allows you to use bolts instead of screws, so that if you pull em in and out several times, you won't degrade the threads. The length wouldn't matter either.

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This is a stupid question but I just wanted to make sure as I've read conflicting information. I built a sealed box for my infinity Kappa sub. I am wired up and ready to finish up by screwing in the sub. I have 1" screws that came with the sub but I used 3/4" mdf for the box. Is it ok to use the 1" screws even though they will pierce through the mdf or should I go get slightly smaller screws that won't go all the way through?

I've read some installers talk about how it's not an issue and to just pilot and screw through while others have said that it will create an issue for the sealed box as air could escape through the screw holes possible resulting in a whistle. Any thoughts or help with this would be greatly appreciated as it's my first box and I'd rather not screw it up on the final step. Thanks
If you experience any air leakage from the screw holes.. adding Clear or the color of you choice of Silicone works just fine after a 24 hour cure time, and fairly cheap. But you should be just fine in most cases. Just make sure you are center on the hole and the rubber seal is in tact for the sub setting.
 
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palvaro

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