owlsplace Posted January 21, 2016 Report Share Posted January 21, 2016 Agreed, ra.ra...An Exacto knife, a fresh blade, and a steady hand can often cut around the original dust cap enough to flip it back. After the re-foam glue is dry remove the shims, re-glue the edge of the dust cap and "close the hatch". Thin cloth dust caps can be troublesome, but most paper and coated cloth AR 12" woofer type dust caps usually work out well.RoyIf you can manage to get under the edge of the cloth dust caps they retain their dimensional stability otherwise they will roll-up on you -- been my experience on two sets done here.Roger Link to comment Share on other sites More sharing options...
RoyC Posted January 21, 2016 Report Share Posted January 21, 2016 If you can manage to get under the edge of the cloth dust caps they retain their dimensional stability otherwise they will roll-up on you -- been my experience on two sets done here.RogerThat is more of an issue with non-coated cloth dust caps, not paper or coated cloth, which are stiffer and retain their shape more easily.Roy Link to comment Share on other sites More sharing options...
michiganpat Posted January 25, 2016 Report Share Posted January 25, 2016 update on mine....got the woofers done using a 30hz test tone, and actually put together one of my 58S's to test. sound great, no rubbing....this is my first time hearing a classic-ish AR 12" woofer speaker, and as far as the low end response, I'm very, very impressed. I've got the other speaker tore apart to recap the crossover. I wanted to get that done this weekend, but life got in the way. Hopefully I can get it done this coming weekend to do a little A-B comparison of an original vs. recapped speaker before diving into the other one.... Link to comment Share on other sites More sharing options...
DavidDru Posted February 9, 2016 Author Report Share Posted February 9, 2016 After getting a bunch of feedback from various sources I decided to go ahead and use shims. I cut out the dustcaps and replaced them when done. A couple of them were a bit ugly so I figured it wasn't worth trying to save the ones that were okay. I have always used the test tone process in the past, but I tell you what, shimming made this easy. The best part being that you can raise the cone up to the correct height so the surround sits better on the masonite ring. With the ring, shimming seems the way to go. For the initial attachment of the inner edge to the cone, what I actually ended up doing was taking half sheet paper towels, wading them up and using them to prop up the cone by wedging it up under between the frame braces and underside of the cone. Worked well enough and it allowed me to leave the dustcaps on while doing that initial gluing. Once dry, I went ahead and cut out the dustcaps and shimmed. Once glued, I just kept going around for about 15 mins and pressing on the edge along the ring. Didn't do any clamping. This was the 2nd refoam on these drivers and it made the inner attachment a little messy compared to usual, but still fine. The bottom photo shows the VC with the inner walls a little off color on this particular one. The others were silver. Evidence of heat? Link to comment Share on other sites More sharing options...
owlsplace Posted February 10, 2016 Report Share Posted February 10, 2016 5 hours ago, DavidDru said: After getting a bunch of feedback from various sources I decided to go ahead and use shims. I cut out the dustcaps and replaced them when done. A couple of them were a bit ugly so I figured it wasn't worth trying to save the ones that were okay..... The bottom photo shows the VC with the inner walls a little off color on this particular one. The others were silver. Evidence of heat? Yes, high current, also the VC wires laying on the cone surface will get hot enough to melt off the cement. Roger Link to comment Share on other sites More sharing options...
Pete B Posted September 21, 2018 Report Share Posted September 21, 2018 On 2/9/2016 at 3:07 PM, DavidDru said: The bottom photo shows the VC with the inner walls a little off color on this particular one. The others were silver. Evidence of heat? Yes, it probably got very hot. Did the other silver ones look like aluminum or some sort of alloy? I've taken one completely apart and it was black anodized on the other side that you can't see. I'm wondering if all of the foam/ceramic magnet AR-11/10pi/9 etc. woofers have metal formers? Link to comment Share on other sites More sharing options...
DavidDru Posted September 21, 2018 Author Report Share Posted September 21, 2018 Been too long ago now Pete that I can not recall. Link to comment Share on other sites More sharing options...
fedeleluigi Posted September 22, 2018 Report Share Posted September 22, 2018 On 9/21/2018 at 4:51 PM, Pete B said: I'm wondering if all of the foam/ceramic magnet AR-11/10pi/9 etc. woofers have metal formers? No they haven't. As regards the 12" foam/ceramic woofers made from about 1970 to around 1977 I have always and only found paper formers, at least so far. So the AR 11/10pi MKI woofers have paper formers, the AR 11/10pi MKII and the following 12" woofers used in the 9 and 9LS series have aluminum formers. Luigi Link to comment Share on other sites More sharing options...
Pete B Posted September 22, 2018 Report Share Posted September 22, 2018 I have an AR-11 replacement woofer that has an aluminum former that was discussed on here years ago but main thread is gone. I wonder if the other one matches. Both are from 1978. Link to comment Share on other sites More sharing options...
fedeleluigi Posted September 24, 2018 Report Share Posted September 24, 2018 On 9/23/2018 at 1:18 AM, Pete B said: I wonder if the other one matches. Both are from 1978. Pete what's exactly the problem with the woofer match? Link to comment Share on other sites More sharing options...
Pete B Posted September 25, 2018 Report Share Posted September 25, 2018 Thanks for your help I should have read your post more carefully as I missed that the AR-11 MKII had metal former woofers. Now I get that both of these woofers should have the metal former. Reading what you wrote carefully: Paper: As regards the 12" foam/ceramic woofers made from about 1970 to around 1977 I have always and only found paper formers, at least so far. So the AR 11/10pi MKI woofers have paper formers, Metal formers: The AR 11/10pi MKII and the following 12" woofers used in the 9 and 9LS series have aluminum formers. These woofers are from 1978 and they should both have metal formers. One way that I test woofers before refoaming is to push the cone to bottom it against the back plate, a metal former makes a clear tap sound, non-metal makes a softer thud. Link to comment Share on other sites More sharing options...
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