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AR-4x Surgery photos--not pretty (and long)

'till I get to them

My AR4Xs are currently bases for my Pioneer CS-63 DXs, untill I get down the to-do list and redo the surrounds.
 
Well, last night I stopped at the local big-box home improvement store and got myself a couple of bags of pink fiberglass insulation. I think it cost just a bit more than $3 per bag. I also got some Aileens Flexible Stretchable Fabric Glue.

I pulled open the AR-4x that I had already recapped and removed the nasty rockwool. It got sealed in a plastic bag and thrown out ASAP. I vacuumed the inside of the cabinet out, just to remove any stray rockwool that might still be hanging around. I weighed one of the bags of fiberglass and found that it weighed just about 12 ounces--Almost perfect.

So I cut it up into chunks--pretty much the way I found the rockwool, and stuffed it in the speaker. I first lined it along the speaker walls, then filled in the middle, which was about the way the original rockwool was put in. Before I covered up the pot, I gave it another squirt of Deoxit Shield, just for good measure. Then the old brown paper napkin went in, and I replaced the woofer.

I thinned the fabric glue with water until it was about the consistency of milk. Using a cheap paintbrush, I painted the thinned glue on the dried out cloth surrounds, making a very thin coat. As of this morning, it hadn't dried completely, but it was still very flexible.

I haven't started on the second speaker, but I think I may try to take photos of the process from beginning to end.
 
Just brought my first pair of 4xs (have had an adopted orphan for a while; details in another thread) and this thread was/is very useful in preparing to renovate them.

Question: I've heard people suggest rubber cement, diluted Elmer's glue (PVA glue), and now diluted Aileen's flexible and stretchable fabric glue, for doping the surrounds. I assume the main purpose of the dope is to seal the cloth surrounds so they remain air-tight, without adversely affecting their flexibility (from original; they may have changed in flexibility over time). Does anyone know WHICH OF THESE GLUES gives the best result, or is it really a case of where the differences would be so miniscule as to be safely ignored? I can get any/all of these glues, and would like the use the "best" one, in terms of performance.

Also, if I read correctly, someone has suggested "hot glue" was used to glue down the grill cloths. If that is the case, could/should one use a blow-drier to warm, and thus soften, the glue, making grill removal easier? Is there any risk to trying this, provided one doesn't go overboard with the heat?

Thanks! :thmbsp:
 
If it dries hard, it's probably not the best choice to dope your surrounds. This rules Elmers out. I've not played w/ Aileens flexible but Aileen's tacky dries quite hard.

If it's not thin, it's probably not the best choice to dope your surrounds. Just make sure it dilutes. Rubber cement has to be diluted with solvents so I'll be avoiding it as well.

My plan is to try to thin some water based silicone sealant and use that (should wrap up my 4x's this weekend).

I would also like some input before I take the plunge :)

TIA!
 
chimpetus said:
If it dries hard, it's probably not the best choice to dope your surrounds. This rules Elmers out. I've not played w/ Aileens flexible but Aileen's tacky dries quite hard.

If it's not thin, it's probably not the best choice to dope your surrounds. Just make sure it dilutes. Rubber cement has to be diluted with solvents so I'll be avoiding it as well.

My plan is to try to thin some water based silicone sealant and use that (should wrap up my 4x's this weekend).

I would also like some input before I take the plunge :)

TIA!
Click to expand...

What you say makes sense: it should be as lightweight and flexible as possible, while still sealing everything airtight (Hhhhmmm, heat-shrunk saran wrap? Just kidding!). The silicon stuff would remain flexible pretty much indefinitely, and can be diluted, so that might be the best choice. Guess I'll try that, too, if nothing better comes up before I start doing it. The only minor fear I would have is that the silicon stuff usually out-gasses ammonia as it dries, and I'm not sure how much that might affect the cloth, but it is only for a relatively short period, so it should be okay. I'll just make sure the surrounds dry well before re-mounting the woofers in the cabinetm so little to no ammonia gas gets trapped inside. It wouldn't be any better than the acid that out-gasses from the old rock-wool! THANKS! :thmbsp:
 
You could re-use the rockwool, just seal it into plastic bags. Thin bags won't affect the sound absorption properties of rockwool since they are acoustically transparent.
 
jeffn said:
You could re-use the rockwool, just seal it into plastic bags. Thin bags won't affect the sound absorption properties of rockwool since they are acoustically transparent.
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I have to disagree with you on this Jeff. Sealing fiberglass, wool, poly, etc. into a plastic bag will only reduce the interior volume of the cabinet and the "tricking" the drivers into thinking they are in a larger space will be negated. If fiberglass dust, etc. is a concern, then staple cheesecloth over the fiberglass. But I wouldn't resuse the rockwool. I'd use AcoustaStuf or similar.
 
Speaking of... Anyone have experience using AcoustaStuf vs. Dacron/poly fiber ? Unless there are significant benefits to using AcoustaStuf, I'll be heading for the fabric store.
 
just get polyfill from the fabric store. speaker guy extraordinaire PaulC here on AK recommends it as his fill of choice. i've used it on several speaker rehabs and am happy with the result.
 
Celt said:
I have to disagree with you on this Jeff. Sealing fiberglass, wool, poly, etc. into a plastic bag will only reduce the interior volume of the cabinet and the "tricking" the drivers into thinking they are in a larger space will be negated. If fiberglass dust, etc. is a concern, then staple cheesecloth over the fiberglass. But I wouldn't resuse the rockwool. I'd use AcoustaStuf or similar.
Click to expand...

Nah..... In acoustics rockwool or fibreglass batts are more often than not supplied with plastic (mylar) film coatings to prevent the fibres becoming a health risk. If there is a difference it will be fairly slight. Even placing perforated steel with only 10% of the steel being open in front of a rockwool batt is considered acoustically transparent. :yes:
 
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