Anybody know what kinda glue is used to hold the magnets on to Carver ribbons?

Jstas
Jstas Posts: 14,707
edited November 2010 in Speakers
I had a rattling in a ribbon. Wasn't sure what it was. Sounded like something bouncing around. So I took the cover off and sure enough, chunks of magnet bouncing around. I cleaned the pieces out and started reassembling. As I'm reassembling, I hear a CLACK and my hand get pinched.

I turn the cover over and sure enough, one of the magnets decides to get up close and personal with an adjacent magnet. It knocked both of them loose. Thankfully, the magnet was not near the ribbon when it happened so there doesn't seem to be any damage.

I should be able to glue these back on and go to town. I'm not sure what glue to use though. Stock stuff looks like contact cement. But I'm not sure. Anybody have any clue?
Expert Moron Extraordinaire

You're just jealous 'cause the voices don't talk to you!
Post edited by Jstas on

Comments

  • disneyjoe7
    disneyjoe7 Posts: 11,435
    edited October 2010
    Jet Glue

    Speakers
    Carver Amazing Fronts
    CS400i Center
    RT800i's Rears
    Sub Paradigm Servo 15

    Electronics
    Conrad Johnson PV-5 pre-amp
    Parasound Halo A23
    Pioneer 84TXSi AVR
    Pioneer 79Avi DVD
    Sony CX400 CD changer
    Panasonic 42-PX60U Plasma
    WMC Win7 32bit HD DVR


  • Jstas
    Jstas Posts: 14,707
    edited October 2010
    Jet Glue?

    Kidding or would you care to elaborate?
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • ESavinon
    ESavinon Posts: 3,066
    edited October 2010
    Check with Toymaker at the carver forum. Those ribbons are a PITA to fix. DON'T and I repeat DON'T attempt to fix them yourself.
    SRT For Life; SDA Forever!

    The SRT SEISMIC System:
    Four main satellite speakers, six powered subs, two dedicated for LFE channel, two center speakers for over/under screen placement and three Control Centers. Amaze your friends, terrorize your neighbors, seize the audio bragging rights for your state. Go ahead, buy it; you only go around once.
  • Ricardo
    Ricardo Posts: 10,636
    edited October 2010
    ESavinon wrote: »
    DON'T and I repeat DON'T attempt to fix them yourself.

    Hey, it's Jstas. He'll be able to do it. Ok, maybe after ruining one or two in the learning process ;)
    _________________________________________________
    ***\\\\\........................... My Audio Journey ............................./////***

    2008 & 2010 Football Pool WINNER
    SOPA
    Thank God for different opinions. Imagine the world if we all wanted the same woman
  • TNRabbit
    TNRabbit Posts: 2,168
    edited October 2010
    I believe it's a slow-curing epoxy. Probably 60 minute.
    TNRabbit
    NO Polk Audio Equipment :eek:
    Sunfire TG-IV
    Ashly 1001 Active Crossover
    Rane PEQ-15 Parametric Equalizers x 2
    Sunfire Cinema Grand Signature Seven
    Carver AL-III Speakers
    Klipsch RT-12d Subwoofer
  • Jstas
    Jstas Posts: 14,707
    edited October 2010
    ESavinon wrote: »
    Check with Toymaker at the carver forum. Those ribbons are a PITA to fix. DON'T and I repeat DON'T attempt to fix them yourself.


    Already contacted DaveS over at the Carver forums. Waiting for a response. Just figured I'd post here as well on the off chance someone else might know too.

    Besides, the ribbons aren't broken. Magnets came loose. I'm gonna fix them myself 'cause $400+ to ship and have them rebuilt just to have magnets glued back on is unreasonable.

    If the ribbon was torn, that'd be a different story.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • thuffman03
    thuffman03 Posts: 1,325
    edited October 2010
    DaveS and Toymaker are the only people I know that know anything about fixing Carver ribbons.
    Sunfire TGP, Sunfire Cinema Grand, Sunfire 300~2 (2), Sunfire True Sub (2),Carver ALS Platinum, Carver AL III, TFM-55, C-19, C-9, TX-8, SDA-490t, SDA-390t
  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    OK, for future reference, "Jet" brand glue is not required. It's a thin set cyanoacrylate glue. Any thin set cyanoacrylate glue will work for this purpose. Actually "Jet" makes a medium and thick set cyanoacrylate cement as well as this thin set glue. The thin set is recommended because it penetrates the porous surface of the ferrous magnets. Essentially it's viscosity and penetrating nature provides for more bonding surface area. However, the cyanoacrylate glues are brittle when dried so they don't flex at all and have a low shear strength. If you are going to use it, be careful when reinstalling the covers because even the pressure of the magnets can flex the covers enough to pop a magnet off.

    As far as doing it yourself, if all you have is broken magnets, some mechanical ability, a set of screw drivers, toothpicks and some patience and you can do it yourself. If the foil has been separated from the ribbons or the ribbons have come unglued completely from the frame, you need special equipment to do it.

    I'm not saying it was easy. It was difficult and tested my patience but I got them fixed. Three out of four of my ribbons had magnets that had popped loose. Two ribbons are in fine shape. The third I am not sure about. I think the magnet that popped off on that one maybe have pinched the foil. I'll play them and see what happens. If it shreds, I'll get it fixed. If it doesn't, yay me!

    As far as cyanoacrylate glues go, it's Krazy Glue or Super Glue and those are thin set as well and available in any drug/grocery/hardware/convenience store. You can get a more flexible version used in suture free surgery. However, they have a low shear strength although are good at bonding to non-porous surfaces. Because of it's low shear strength though, I'm wondering how effective it is in the long run at securing the magnets. In the Platinums, the poles on the magnets are end to end while in the non-Plats, the poles are along the lengths. This means they are fight each other in close proximity. Add to that the fact that it's not so hot at bonding porous surfaces, even in the "penetrating" thin set versions, I only seeing it weakening the bonds further in relation to shear strength.

    Either way, the ribbons are reassembled, remounted and I'll give the magnets 24 hours to set fully and we'll see how it goes tomorrow.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    Oh, gotta add, the surgical or medical grade glues are not an industrial grade. They are more flexible, yes, but the bonding strength is reduced by additives meant to reduce the irritation level of the glue to skin. So it's not a viable alternative to the "professional" or "industrial" grades. Super glue and Krazy glue are industrial grade.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • ben62670
    ben62670 Posts: 15,969
    edited November 2010
    You can get a more flexible version used in suture free surgery.
    Where?
    Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
    Thanks
    Ben
  • nooshinjohn
    nooshinjohn Posts: 25,033
    edited November 2010
    If I had read this thread earlier John, I would have asked Bob about it as we were talking about my amps.:smile:

    Once those magnets are set back in place, can an epoxy type adheisive be used to make the bond more stable, kind of like what we have been doing on the SDA drivers?
    The Gear... Carver "Statement" Mono-blocks, Mcintosh C2300 Arcam AVR20, Oppo UDP-203 4K Blu-ray player, Sony XBR70x850B 4k, Polk Audio Legend L800 with height modules, L400 Center Channel Polk audio AB800 "in-wall" surrounds. Marantz MM7025 stereo amp. Simaudio Moon 680d DSD

    “When once a Republic is corrupted, there is no possibility of remedying any of the growing evils but by removing the corruption and restoring its lost principles; every other correction is either useless or a new evil.”— Thomas Jefferson
  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    I don't know.

    Look for the trade names: derma+flex® QS™, SurgiSeal, FloraSeal, Dermabond, Surgi-Lock and Nexaband

    I never had to buy them. We had them on the ambulances but that was bought from a medical supply distributor. You really can't use it for anything requiring more than 3, maybe 4 stitches. Since you're not a doctor, I wouldn't necessarily recommend doing it yourself.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • F1nut
    F1nut Posts: 49,704
    edited November 2010
    I would have asked Bob about it as we were talking about my amps.

    Why, he wouldn't know. Dave and James are the masters at all things ribbon related.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    F1nut wrote: »
    Why, he wouldn't know. Dave and James are the masters at all things ribbon related.

    Which is who I spoke to about it and they recommended "Jet" glue. It seems to work well enough and for the Plats, it's a fine solution. The magnets don't fight each other as much because of how the poles are oriented. I'm just concerned about long-term viability in the non-Plat models.

    I also wanted to point out that if "Jet" brand glues are not available to you easily or locally that you don't necessarily need to use that glue as any thin set/penetrating cyanoacrylate glue will do the same thing. Most hobby shops, especially those that deal with radio controlled cars and Lexan bodies, will have this glue from any number of brands. So don't kill yourself looking for "Jet" specifically like I did and end up waiting almost 3 weeks for a .5 oz. bottle to show up in the mail.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • HB27
    HB27 Posts: 1,518
    edited November 2010
    I used permatex 2 part epoxy on my Amazing Silvers.
    The magnets really fight each other and I had to clamp them overnight to get them to hold.
    I also punctured a place on the foil ribbon repairing them. I used an automotive "Rear Window defroster" repair kit on the foil for the small tear i put in it. It worked great. I got very lucky.
    I did call Dave for some guidance on the repair project and I'll say he was most helpful and gracious with his time and advice.
    Thank you again Dave for your help.
  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    I would imagine that epoxy to be a pain in the **** to work with. Clamping couldn't be easy either since a typical steel C-clamp or spring clamp could end up pulling more magnets off. You'd have to use aluminum or wood block clamps and cinch them down tight. That risks damaging the finish on the metal ribbon covers and warping the covers. So if you're doing it that way, be careful.

    The nice thing about the cyanoacrylate glues is that they bond instantly. You only have to hold down with moderate pressure for a few minutes (2-4) and then the bond is there and you can go about your day and give it some time to cure completely before pressing it in to service.

    There is another glue I've used when repairing fiberglas, urethane and such. But, for the life of me I cannot remember what it is. I have to go look it up when I get time. It's also instant bonding, is just as strong as the cyanoacrylate but is flexible and has a fairly good shear strength. It might be a better alternative.

    However, the rearview mirror glue thing, can you elaborate on that? Did Dave give you that suggestion or did you make it up yourself? I'm just wondering because it seems that the activator would melt the ribbon. Or at least it seems so to me.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • dorokusai
    dorokusai Posts: 25,573
    edited November 2010
    Elmers....the kind you find in 1st grade.
    CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    dorokusai wrote: »
    Elmers....the kind you find in 1st grade.

    Was anybody talking to you, jackwagon? Shut your pie hole and go find someplace else to fester in your own pathetic self-hate.
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • HB27
    HB27 Posts: 1,518
    edited November 2010
    Jstas wrote: »
    I would imagine that epoxy to be a pain in the **** to work with. Clamping couldn't be easy either since a typical steel C-clamp or spring clamp could end up pulling more magnets off. You'd have to use aluminum or wood block clamps and cinch them down tight. That risks damaging the finish on the metal ribbon covers and warping the covers. So if you're doing it that way, be careful.

    The nice thing about the cyanoacrylate glues is that they bond instantly. You only have to hold down with moderate pressure for a few minutes (2-4) and then the bond is there and you can go about your day and give it some time to cure completely before pressing it in to service.

    There is another glue I've used when repairing fiberglas, urethane and such. But, for the life of me I cannot remember what it is. I have to go look it up when I get time. It's also instant bonding, is just as strong as the cyanoacrylate but is flexible and has a fairly good shear strength. It might be a better alternative.

    However, the rearview mirror glue thing, can you elaborate on that? Did Dave give you that suggestion or did you make it up yourself? I'm just wondering because it seems that the activator would melt the ribbon. Or at least it seems so to me.

    It's not a glue. It's an adhesive contact tape that had the cosmetics of the ribbon. I've also used it on circuit board repairs. I get it at AutoZone. Kinda like alarm tape.
  • Jstas
    Jstas Posts: 14,707
    edited November 2010
    HB27 wrote: »
    It's not a glue. It's an adhesive contact tape that had the cosmetics of the ribbon. I've also used it on circuit board repairs. I get it at AutoZone. Kinda like alarm tape.

    Well what did you fix with it? Did the ribbon have a hole in it or was the foil separated from the ribbon? Did you overlap the hole/tear with it? Did that change the response of the speaker any?
    Expert Moron Extraordinaire

    You're just jealous 'cause the voices don't talk to you!
  • HB27
    HB27 Posts: 1,518
    edited November 2010
    Jstas wrote: »
    Well what did you fix with it? Did the ribbon have a hole in it or was the foil separated from the ribbon? Did you overlap the hole/tear with it? Did that change the response of the speaker any?

    I fixed a hole in the outer covering with it. It blended nicely and was hardly noticable. THat's been a couple of years ago and IIRC I did some damage to the ribbon right on the edge next to the magnet and the defroster tape worked there too.
    I sold them not long after that and they held up fine with no sound issues to them.
    I had to do the self repair as it was difficult to come up with about $460 or so to rebuild the ribbon.
  • AudioGenics
    AudioGenics Posts: 2,567
    edited November 2010
    could you use 3M Super 77
    Multipurpose Adhesive

    ..."bonds many foils, plastics, papers, foams, metals, and cardboard."

    I used it to repair the ribbons on Magnepans.
  • Hi best glue is locktite 945. i saw a bottle of it on a photo of the guy who repairs them, tried it and it is fantastic.
  • VR3
    VR3 Posts: 27,964
    About 8 years late to the party blitz
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.