Waterproofing MDF sub box....

[Jakkle5 10+ year member]

Any ideas? Built a 3/4" MDF sub box for my boat. Box will be under one of the seats facing out into the cabin but will still have moisture around it. What can i use besides a layer of fiberglass to completely waterproof it? BTW its salt water if it matters.

Thanks

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[PatFitz9 10+ year member]

is the sub waterproof? and why not just make the enclosure out of fiberglass, rather than wrap MDF in glass?

 

[Jakkle5 10+ year member]

The sub is waterproof. I didnt want the hassle and didnt have the time to make it out of fiberglass so i figured i could just wrap it once or twice in fiberglass and be done.

 

[iamamp3pimp 5,000+ posts]

if you glass it, that will waterproof it.

polyurthane wil do it too.

 

[Anthony Collova 10+ year member]

We have a bunch of customers that use our Spectrum coating on the outside of the box. Water based polymers stick very well to wood, and will add some added sound deadening results (not that MDF needs much help).

Most any vibration coaintg you use will be water resistant and will help you achiev your goals.

ANT

http://www.secondskinaudio.com

 

[SentraStyle 10+ year member]

You could just coat the box in fiberglass resin (don't really need to use fiberglass mat) and then carpet it. I've been doing that for years for a boat dealership that regularly brings boats in for systems...haven't had not one come back yet with water damage.

 

[jdawg 5,000+ posts]

bedliner material

 

[Jakkle5 10+ year member]

You could just coat the box in fiberglass resin (don't really need to use fiberglass mat) and then carpet it. I've been doing that for years for a boat dealership that regularly brings boats in for systems...haven't had not one come back yet with water damage.

Should i put the hardener in with the resin also or just straight resin? This is kind of what i was hoping to hear. Resin and then carpet.

 

[Flipx99 5,000+ posts]

We have a bunch of customers that use our Spectrum coating on the outside of the box. Water based polymers stick very well to wood, and will add some added sound deadening results (not that MDF needs much help).
Most any vibration coaintg you use will be water resistant and will help you achiev your goals.

ANT

http://www.secondskinaudio.com

Can it be sanded smooth and painted?

 

[Jakkle5 10+ year member]

We have a bunch of customers that use our Spectrum coating on the outside of the box. Water based polymers stick very well to wood, and will add some added sound deadening results (not that MDF needs much help).
Most any vibration coaintg you use will be water resistant and will help you achiev your goals.

ANT

http://www.secondskinaudio.com

could you quote me a good price on a gallon of this plus a spray gun? Thanks!

 

[SentraStyle 10+ year member]

Should i put the hardener in with the resin also or just straight resin? This is kind of what i was hoping to hear. Resin and then carpet.

Yeah, definately use hardener as well...unless you want a big mess. Just mix the resin and hardener as you would if you were going to fiberglass something...but then just brush on the mixture to the box (I usually do it inside and outside of the box just to be safe).

 

[The_spacemonkey]

We have a bunch of customers that use our Spectrum coating on the outside of the box. Water based polymers stick very well to wood, and will add some added sound deadening results (not that MDF needs much help).
Most any vibration coaintg you use will be water resistant and will help you achiev your goals.

ANT

http://www.secondskinaudio.com

Ant, you ever have a problem with the MDF swelling from the water content in the deadener? Just wondering //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

You could used rubberized undercoating, though you really cant sand that down. The best thing for a nice smooth surface would be fiberglass resin.

 

[audioholic 5,000+ posts]

Straight resin (w/ hardener) would be best.

 

[tapout 5,000+ posts]

http://www.herculiner.com/

http://www2.northerntool.com/product-1/47722.htm

 

[azbass 5,000+ posts]

Should i put the hardener in with the resin also or just straight resin? This is kind of what i was hoping to hear. Resin and then carpet.

um, you need to use hardener (mekp) with the resin, so it can cure.