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Nightmare refoam

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Aw, man - I helped hijack my own thread! Somebody STOP ME!

Anyway, back to the restore: My final solution for the dustcap.

The original dustcap is thick felty paper, and it is flat, not a bowl shape. I took the larger paper caps that were included (less curvature) and cut out a piece from the center that would sit on the rim left by the original dust cap - no glue on the cone. I'll post pics Monday or Tuesday.
 
Shims, a first-timer's opinion

In the end, I was glad I used the shims. I don't have any signal generators or test cd's, and I am a complete novice at all of this.

There is SO MUCH talk about getting the VC centered, I did not want to screw it up and the shims were a safe bet. I agonized about cutting the dust caps. I had no idea what a VC or spider looked like, or how they worked. I was afraid of cutting the wires (also talked about a lot) but I was more afraid of not getting the surround right. The shims took all the stress out of it, and once I got in there it was easy. I would be willing to try one without shims in the future, if I get a test cd for the collection (I plan to).

I don't think the dust cap plays a big role in these woofers, in this cabinet. I couldn't hear a difference in the bass even while the dustcap was completely removed. And the shims gave me confidence to go it alone, on the good faith that if MarkAnderson can do it :naughty: how could I f@#k it up? :thmbsp:
 
Update

I couldn't find any Jasco's (long way from here to a Home Depot), alcohol was having NO effect, and the "doughnut glaze" glue was being unforgiving to the scraping, so I applied some acetone! :no: Now the glue has reverted to a rubbery state, it is more firmly than ever attached to the cone, and even more resistant to the effects of scraping.

I'm open to more suggestions, I got nothing.
 
Softening is a change of state. Sounds like progress. What about applying a bit more and waiting to see what happens over time. A break-down process may be in the works.

What do you think? Any change in the glue since you applied the acetone?
 
Kencat said:
Softening is a change of state. Sounds like progress. What about applying a bit more and waiting to see what happens over time. A break-down process may be in the works.

What do you think? Any change in the glue since you applied the acetone?
Click to expand...
Good point, Kencat. I'll give it another dose and see what happens. The cone material does NOT like the acetone, I won't be able to do anyhting with it until it evaporates completely. Currently the adhesive is still in a rubbery state, far cry from the hard glazed substance I was shaving off a molecule at a time.
 
It's too bad I wasn't watching this one closely enough I could have supplied you with exact (virtually) replacements for the flat dust caps. I found them awhile back an ordered them up when I started refoaming old AR woogers. And when I had a 2ax reconed I supplied the flat cap to the reconer who used it in place of the dome cap they would have used so they wooger looks closer to original. Another thing to mention about the "to shim or not to shim" subject is that some VC gaps are a lot smaller than others and your room for error when refoaming may be very small. Although I've been told by some close AKers that they haven't had any trouble when not shimming I have always shimmed and haven't had any problems with the results. And shimming does help hold the cone in place when working on it.
 
ARguy said:
It's too bad I wasn't watching this one closely enough I could have supplied you with exact (virtually) replacements for the flat dust caps. I found them awhile back an ordered them up when I started refoaming old AR woogers. And when I had a 2ax reconed I supplied the flat cap to the reconer who used it in place of the dome cap they would have used so they wooger looks closer to original. Another thing to mention about the "to shim or not to shim" subject is that some VC gaps are a lot smaller than others and your room for error when refoaming may be very small. Although I've been told by some close AKers that they haven't had any trouble when not shimming I have always shimmed and haven't had any problems with the results. And shimming does help hold the cone in place when working on it.
Click to expand...
Thanks, ARguy! If I end up doing another pair (and I HOPE I do!), I'll keep you in mind. And I agree, the shims are a boon in that they will hold the cone in a suspended position while you prepare to attach the surround to the basket.
 
If you give up, I have a pair that I yanked from a destroyed pair of AR2a cabinets. Also have the dome tweeters.
 
Update

UPDATE: Thanks to Starmover for the parts! The shipping damage was a little worse than I realized at first - one of the tweeters was busted completely off it's mount ring! I replaced the caps with solens, and replaced the "modern" plastic-bodied tweeters with Starmover's earlier resin domes. The earlier model woogers (little brother of the AR3 style - ribbed cone, felt pad) will NOT fit into the openings for the more modern "plain" wooger design.

So, I ground as much of the old residue off as I could, patched the ragged spots (Acetone + AR felt wooger = :nono: ) with Aileene's and coffee filter, and stuck the new surround down with a heavy dose of adhesive, adding a little bead to the inside edge of the surround after it was attached to make sure it sealed.

The wooger works just fine, no noticeable difference to my tin ear anyway from one to the other. The biggest difference is in the top end - I highly recommend the early model tweets for these speakers! The top end is now very clean, crisp, and clear compared to before. Thanks to everyone who chimed in with opinions!
 
oz - so you now have two working pairs of 2ax's, right? So how do they sound stacked? :scratch2: - Mark

BTW, sorry things didn't work out for tonight (it's Fotno's fault :D ), but I'll be up there in a few weeks.
 
Infinity Quantum Woofers

Bob E. said:
First off, thanks for posting this, I am following along eagerly! I am in the midst of my first re-foam...



I have been agonizing about this, but I don't think I will be removing these "dust-caps" -- they are "way down in the valley", so to speak, and I don't want to cut them. These are 10" woofers from Infinity RSb units, so the poly cone was a blessing as far as glue clean-up, much more rugged than paper cones. I think I will do a shim-less refoam and see how it goes.

--Bob
Click to expand...

Hi Bob, you do not want to cut those caps off. They aren't a stock cap and you won't find them anyplace.

By coincidence, I just finished hanging new suspensions on the exact same driver pair for a customer. How do I align it? It takes a lot of practice to learn how to centre the voicecoil uniformly in the magnet gap by the "freehand" method. Like with anything, practice is the way to learn. Suspensions are relatively inexpensive (if you don't first succeed) and thankfully poly is indeed a breeze to clean compared to paper, but paper is certainly a superior medium for cones by a wide margin.

Thank goodness that infinity cone is convex in shape and relatively deep for some added rigidity otherwise it'd be just another mill-run poly peice of crap (don't tell my customer I said that!). Give it a whirl and see how it goes.
 
(Regarding Infinity RSb refoam job)

ARRAY said:
Hi Bob, you do not want to cut those caps off. They aren't a stock cap and you won't find them anyplace.
Click to expand...

Thanks, that confirmed my suspicions. I've completed the re-foam on one of these guys, but haven't reinstalled it to test yet. However, I do feel pretty good about the prospects of success. I will describe my technique for centering without shimming in another thread when I get some pics of the second re-foam job, so as not to hijack this thread any further (sorry, Ozmoid!).

--Bob
 
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