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Shaun M
12-09-2015, 07:59 AM
Does anyone know how to fix a 2225 sagging spider? The cone has also dropped slightly. Thanks

68627


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NickH
12-09-2015, 08:12 AM
I know its been mentioned on here, a way to restore them. I recall it involved heating the spider up with hot air, I think. But it seems to me the only real way is to recone the driver.

I think it was heat the spider with a heat gun and the let it cool with the driver upside down or the like. But if phenolic is what's used to make the spider I do t see how it really works. Phenolic is a thermal setting polymer. Meaning once its heat cured it will not soften again with heat.

Nick

gasfan
12-10-2015, 03:49 PM
I have a pair of 2203H with the same problem. By the looks of them, it appears as though the foam surrounds could be the culprits by shrinking and consequently pushing the cone back. Anything to this or is this just my imagination? The force it takes to pull the cone up into position seems much more than the tension being exerted by the spider. They are medium stiffness. Once the foams are replaced, could the spider be doped while supporting the cone until dry? I mean a very light coat adequate to maintain it's shape while also rejuvenating it to an extent.

Wagner
12-10-2015, 04:08 PM
What type of surround does this driver have? (should be paper, yes?) If paper or cloth, try the following (although you could try it with foam if it's still intact and not rotted)

Lift the cone to the proper height with small pieces of polyfil or similar (a cut up sponge will work) tucked between the cone and the frame
Take care and make things as concentric as possible and get the spider level

Then make a 50/50 mixture of 99% isopropyl alcohol (if you can find it) and water

Brush the SURROUND ONLY, NOT THE CONE and the spider too, GENTLY (just enough to get everything wet) ONE PASS worth, don't "scrub" things with the water and alcohol mix and don't "soak" it dripping wet; just get it wet

Allow to dry over night and then see what you've got; if you can see progress but not a total "fix" you can try a repeat

Try it at least twice before resorting to adhesives

I've saved more than one ancient driver that way for which there was absolutely no parts available without extensive fabrication

If that doesn't do it, the next thing you can try is to do the same polyfil cone and spider lift, but this time brush an even coat of a thin PVA on the surround ONLY, do not put it on the cone or the spider

Elmer's Glue All thinned with water will work just fine; thin it so it will brush on like paint without leaving marks

If the 50/50 mixture DOES give you good results and a driver that now plays reasonably well it won't hurt at this point to treat a paper edge with a thin coat of PVA as a protective/reinforcement/strengthening measure
Just leave the polyfil or sponge bits in place any time you are wetting that outer compliance (surround) to keep things in their proper place and level

I do NOT recommend putting anything on a spider other than the 50/50 mix and only then, judiciously as described. The only exception is when making a repair (the spider is coming loose from the motor assembly) like is/was common with the old "AR" woofers

Good luck

Thomas

gasfan
12-11-2015, 07:06 AM
Bump.