owlsplace Posted June 13, 2015 Report Share Posted June 13, 2015 No apologies necessary on the thread -- it's not over until it is over That is what I call rock wool.The shroud material -- Kimpac or similar name I often replace with thrift store chiffon fabric when it is shredded. I think Infinity used a loose weave buckram which is available at Hobby Lobby.The terminals on the pots look pretty decent so perhaps the pots are restorable. Good show,Roger Link to comment Share on other sites More sharing options...
ra.ra Posted June 14, 2015 Report Share Posted June 14, 2015 Very nice pics - - thanks - - I particularly like the shots from inside the cabs showing the installed midrange and tweeter and the T-nuts, and I always find it interesting when you find walnut veneer on the interior. Also, I always like seeing that little guy on the ink stamp who shows up from time to time.Just one question: why no investigation or testing of the potentiometers or capacitors? While the speakers are open, now is the time. Link to comment Share on other sites More sharing options...
glenz66 Posted June 14, 2015 Author Report Share Posted June 14, 2015 Excellent - Until the end!That is it. KIMPAK - Cellulose Wadding. Thank you for the knockoff suggestions, Roger for I do not see other than bulk options for purchasing. I am slightly concerned about using the original material with it being tainted from the rock wool. (i.e. the transfer of rock wool particles) That may be a sensitive concern but unless I hear otherwise...For now, I am set with recommended 3 bags per speaker of Johns Manville B-777 fiber glass insulation. As a quick non-scientific hand in hand check, the weight feels proper to the original. I need to open the original speaker (Edit - the one that was not yet opened by others) to see how they packed the stuffing around the woofer area to be sure, but as I understand it, one should not overstuff behind the woofer before laying the new shroud of Kimpak to protect the back of the woofer from the insulation.My main goal for opening the AR-2ax’s up is to rejuvenate all that is possible to ensure that I have a properly working set speakers. All the parts (with the exception of the Kimpak substitute) have arrived and are calling for me to let them live so that I may hear “the food of love” again. But now that you mention it, ra.ra, it would be a fun learning exercise the test all of the components before I go further in dissembling the original potentiometers and capacitors. The thing is I do not yet fully understand how to go about doing the tests.I have a multimeter and I know to discharge a capacitor before working on it but I failed to obtain a capacitance meter. Is there a thread that I missed that details how to go about checking the drivers and all for compliance? Again, I thank you all for helping me earn the title of “Advanced Member” that was heaped upon my shoulders two or three posts ago. In the end, if the original potentiometers check out as restorable, I will find another home for them down the road but in the name of action they are being evicted from their current establishment. In the meantime, I am studying the fine arts of soldering. Link to comment Share on other sites More sharing options...
owlsplace Posted June 14, 2015 Report Share Posted June 14, 2015 Excellent - Until the end!...I have a multimeter and I know to discharge a capacitor before working on it but I failed to obtain a capacitance meter. Is there a thread that I missed that details how to go about checking the drivers and all for compliance? Again, I thank you all for helping me earn the title of “Advanced Member” that was heaped upon my shoulders two or three posts ago. In the end, if the original potentiometers check out as restorable, I will find another home for them down the road but in the name of action they are being evicted from their current establishment. In the meantime, I am studying the fine arts of soldering.Don't have much to worry about discharging speaker capacitors -- power supply caps are a differenct story.Clue us in on the details of the pots in your photo.Simple to do DC resistance checks on each driver with your multimeter. Link to comment Share on other sites More sharing options...
glenz66 Posted June 14, 2015 Author Report Share Posted June 14, 2015 "Simple to do DC resistance checks on each driver with your multimeter." -- That is Greek to me but I am learning.I hope that I am not posting too many photos.Prior planing is not always the best in these situations. I think the potentiometers are looking fairly good. Well, on to the next stage. Installing the new items. Link to comment Share on other sites More sharing options...
DavidDru Posted June 14, 2015 Report Share Posted June 14, 2015 Hmmm, those pots are more black with corrosion than the blue/white stuff. Have you tried cleaning that off yet and if so how they look after?So there was not stamp on the side wall inside the cabinet? Anybody know if that 5717 stamp means anything? Link to comment Share on other sites More sharing options...
owlsplace Posted June 15, 2015 Report Share Posted June 15, 2015 "Simple to do DC resistance checks on each driver with your multimeter." -- That is Greek to me but I am learning.....Prior planing is not always the best in these situations. I think the potentiometers are looking fairly good. Well, on to the next stage. Installing the new items.Actually, I was asking about details on the new pots you have.Here is basic DMM resistance measurement proceedure: http://www.wikihow.com/Measure-ResistanceRoger Link to comment Share on other sites More sharing options...
glenz66 Posted June 15, 2015 Author Report Share Posted June 15, 2015 I will be sure to look at the original rheostats later on to see if they can be restored. Now that I revisited the photos above I can see where the corrosion kept at least half the spectrum from making contact so I am glad that the decision was made to open them up. But I tell ya, right now my nerves are shot and I am ready for a few fingers of Scotch...I hope beyond all hope that my solder joints are acceptable! And I am not happy that I crimped my common wire with the clamp holder. I learned not to use the teeth to hold. Other than that, what do you all think of my solution to the Kobayashi Maru?Need to wait 24 hours for the Goop glue to hold. Link to comment Share on other sites More sharing options...
owlsplace Posted June 16, 2015 Report Share Posted June 16, 2015 Ok, some of those pots are hard to solder to but work well with female spade connectors, no soldering required; otherwise, I would strip your wire longer, twist the strands tight and pass through the hole and wrap once around and back to itself. Your solder joints need to be shiney or you are not getting enough heat on it.What kind of pots are those? And you have a plan for a cover?Roger Link to comment Share on other sites More sharing options...
glenz66 Posted June 16, 2015 Author Report Share Posted June 16, 2015 Thank you for the basic resistance measurement link, Rodger I will start there and move in a forward direction. I also appreciate the solder critique. It all makes sense now. The new rheostats and capacitors, along the upcoming grill cloth, was a one stop shop from Carl's Custom Loudspeakers. With instructions...That is why I did not have to bug you all with the layout. :-)I am not sure about the rheostat cover. I was thinking of a four post canopy of loose weaved material, a balsa wood structure, or a structure built out of 1/2" thick sponges. Link to comment Share on other sites More sharing options...
ar_pro Posted June 16, 2015 Report Share Posted June 16, 2015 Here's a couple of pages from a Dynakit manual that show their recommended soldering method.Heathkit used to include a "Kit Builders Guide" with each kit, and it was an excellent introduction to the skill.These guides are on eBay for just a few bucks.Heath also offered a complete soldering course called "Soldering", with a more involved manual.These turn up on eBay as well. Link to comment Share on other sites More sharing options...
owlsplace Posted June 17, 2015 Report Share Posted June 17, 2015 Can't go wrong with Carl backing you up.Those pots will get hot if the speakers are driven hard so you need to keep flammable material at a distance.Here is an example of a catastrophic meltdown: Roger Link to comment Share on other sites More sharing options...
glenz66 Posted June 20, 2015 Author Report Share Posted June 20, 2015 The good news is that I found a buyer-friendly quantity of the cellulose wadding on eBay and it will be arriving next week. The bad news is that I lost my nerve on my plans to cover for the new rheostats and I have been wandering aimlessly looking for nonflammable loose-weaved material. Do you all have suggestions on how to cover those buggers? But apart from the lament above progress prevails: Link to comment Share on other sites More sharing options...
owlsplace Posted June 21, 2015 Report Share Posted June 21, 2015 I was toying with the idea of using 1/8" hardware cloth to make a cage before opting for a simpler solution -- only had one pot to cover.That meltdown photo above was kind of an extreme example.Roger Link to comment Share on other sites More sharing options...
glenz66 Posted June 21, 2015 Author Report Share Posted June 21, 2015 Perhaps we are overthinking this but inspired by your AR-5 story I was thinking of reusing the old grill cloth as a cover.You kind of get the idea from the photos. Egg carton separates as pylons and 45 year old grill cloth as cover glued and stapled. What do you think? Should I do it? Link to comment Share on other sites More sharing options...
owlsplace Posted June 22, 2015 Report Share Posted June 22, 2015 Hmmm, I'd go for something more rigid ... maybe you can add some bracing dowels from the baffle to the back and mount a cover to those. Kent likes to add bracing if I remember correctly he has some links. I think I have the links also but my computer is down currently.Roger Link to comment Share on other sites More sharing options...
glenz66 Posted June 22, 2015 Author Report Share Posted June 22, 2015 I know we just need to cover the rheostats but it will be piecemeal job in doing so. Covering the whole crossover board would be a cleaner look. If the speaker cloth can cover the top only, I can use a loose layer of cellulose waddling along the sides before packing in the new stuffing. What say ye? Shall we shake on this one? And thank you for all of your advice! Link to comment Share on other sites More sharing options...
owlsplace Posted June 22, 2015 Report Share Posted June 22, 2015 Okay, sides open ... how about a piece of hardboard or 1/4" ply for a cover. Link to comment Share on other sites More sharing options...
ra.ra Posted June 22, 2015 Report Share Posted June 22, 2015 I like your sketch, glenz66, but after the recent discussion of ignited voice coils and melted pots, maybe a fine layer of flammable speaker cloth near to any source of potential heat is not the best choice of material. Perhaps a thin piece of bent and shaped perforated metal would better suit this purpose. Link to comment Share on other sites More sharing options...
glenz66 Posted June 23, 2015 Author Report Share Posted June 23, 2015 I am a little worried about using metal inside the speaker cabinets. I just have the thought of dampening and possible wire contact running through my head but point taken from you both on the 45 yr old speaker cloth. I think the 1/4" hardboard rheostat sandwich is a very appealing solution. Now if I can only reproduce that dude that is stamped inside the cabinets it would be fun to silk screen or sketch it out on the front of the rheostat cover but I fear that I will not have patience once the waddling arrives. Thanks guys! Link to comment Share on other sites More sharing options...
glenz66 Posted June 28, 2015 Author Report Share Posted June 28, 2015 I am extremely happy to say that my 2-1/2 year journey from "Songs of a Wayfarer" is near its end. Speaker #1 is ready for connection!And now to present the crossover cover! I was somewhat concerned about expansion & contraction loosening the screws though time so I bonded both sides of the wood spacers along with a shot down the drill hole with the Goop glue. I then, without pause, secured the cover to the crossover board with (4) 2-1/2" screws/washers and let the glue do its thing. Next I covered the structure with a layer of cellulose wadding to protect the rheostats from the new layers of insulation. The new stuffing was then packed in and around the speaker -- Roughly 2 bags in the upper mid /tweeter section and 1 bag in the lower woofer area. Lastly, a fresh layer of the cellulose wadding was used to contain the insulation in the cabinet and protect the backside of the woofer.And now we move along to the woofer's final placement.I figured it would be easier to lay the speaker dope in before the final wire soldering so that was next. I just winged the amount of speaker dope to use. I was trying for a 1/4" round bead but ended up with a layer about 3/8" in spots.And then the fun part! Reconnecting the woofer with my new found soldering skills. Call out to Roger's direction & ar_pro's excellent diagrams and advice. Check it. Final seating and lock down of the woofer. I was concerned about warping the outer rim of the woofer when it came to this leg of the journey; i.e. With the uneven layer of speaker dope and tightening the screws to much on one side vs another. The main concern was that the added stress on the outer rim would help to unloosen the cloth surround though time. To combat this concern, I tightened the screws as I pressed the woofer in the new speaker dope then backed off the presser and repeated the same until I felt it was evenly dispersed. I then waited 24 hours for a final turn of the screws. And so ends this road as I turn from it with a smile...Thank you!Greg Link to comment Share on other sites More sharing options...
tysontom Posted June 28, 2015 Report Share Posted June 28, 2015 Suggestion for the use of Mortite: it's not necessary to put a huge amount of the material on cabinet cutout to seal the woofer, as in the case of Greg's nice AR-2ax project. Putting too much Mortite can cause the woofer frame to flex a bit during the tightening process, and it would be difficult to pull the frame down adequately without putting a lot of pressure on the frame itself. Usually, the best way to use Mortite is to make pencil-sized (approximagely 3/8-1/2-inch diameter) rolls of the material around the outside edge of the recessed cutout, being sure that the material around the screw holes seals properly. Once in place and the woofer tightened (tighten the screws as you would tighten the lugs on a car tire, criss-crossing opposite screws until tight all the way around), gently push in the woofer (from the apex) approximately 3/8-inches) and release, noting that the woofer returns fairly slowly. This is not a scientific test, but it is a general test that is effective in determining the seal (considering that the surround is okay, too). Again, the seal is not intended to be "air-tight," but it is intended to be an "acoustical" seal sufficient to seal the woofer down to its lowest operating bass frequencies of around 40 Hz.—Tom Tyson Link to comment Share on other sites More sharing options...
ar_pro Posted June 28, 2015 Report Share Posted June 28, 2015 Yeah, that's good work, Greg.Placing your little note to the future is pretty cool, too - I love when I find things like that.Great-looking vintage Sansui, as well! Link to comment Share on other sites More sharing options...
glenz66 Posted June 29, 2015 Author Report Share Posted June 29, 2015 Encore photo with new grill cloth! :-)Thank you all for the comments and correct name for what I was calling speaker dope. I did the TT woofer check and the surrounds came back slowly so it looks like we have an acoustic seal. And with one final thanks across the board I will bow out of this thread and leave it drift through time in the archives.P.S.Kent? If you still have those AR buttons... Link to comment Share on other sites More sharing options...
owlsplace Posted June 29, 2015 Report Share Posted June 29, 2015 Congrats, nice job! Let's get it on as Carl says, "It's all about the music." Link to comment Share on other sites More sharing options...
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