magnetic shift insurance

[zarrdoss]

I have a lot of time sitting around the house and being quiet so I decided to get some hefty adhesive and glue around all the magnets around the top plate and bottom on the magnet to prevent loosing a driver to magnetic shifting. I figured what the hell better than doing nothing.

43063

43064

I pulled out one driver at a time and glued it and then replaced it. The glue set up fast so no dripping, then left the last one out and put a small fan blowing inside to help dry faster and will put the last one in tomorrow when its all good and dry.

Take care.

[skrol]

What adhesive are you using?

[zarrdoss]

Its called quick grip, seemed to work really well on the trial speaker. Anything that bonds to metal and ceramic should work. now only 24 more drivers to go!

[zingo]

I have a lot of time sitting around the house and being quiet...


...now only 24 more drivers to go!

You aren't kidding!

[WilliamM2]

I've never seen or heard of a magnet seperating where you glued it. Usually, they seperate from the basket, and the peices you glued shift or fall off, still attached together.

[zarrdoss]

the basket is riveted on to the top plate, here this will help

http://www.polkaudio.com/forums/showthread.php?t=87460&highlight=magnet+shift

[WilliamM2]

the basket is riveted on to the top plate, here this will help

http://www.polkaudio.com/forums/showthread.php?t=87460&highlight=magnet+shift

Interesting. Here is the method I have seen used before, glad I didn't bother.

http://www.polkaudio.com/forums/showpost.php?p=936784&postcount=1

It made sense to me at first, the only magnet failure I have had was on a set of Rti-28's, and the magnet seperated from the basket. There were no rivets on that speaker.

[madmax]

So, they are held on with rivets. How do you reinstall the assembly to the speaker basket?

[gdb]

I have done some research and preliminary tooling to "re-center" the shifted pole plates and magnets on the MW65XX series of drivers. As far as I can tell so far.... the "base" plate is fastened to the basket by 4 rivets and ain't going anywhere anytime soon. Most often it is the pole (outermost) plate that shifts when the adhesive fails, sometimes the magnet itself detatches from the base, with the pole plate still centered on the magnet. To really insure that all pieces stay put I put a heavy bead of JB Weld on both sides of the magnet, right up against the two plates. Prior to applying the JB, I use a professional grease & wax remover from an auto body supply shop to get everything absolutely clean. I don't ever expect to have the drivers fail due to shifting after performing this procedure. Fingers crossed !!! Link to thread with pics of a MW6510 that was "disassembled" by a member which I have gratefully obtained from geoff727. I am still interested in acquiring more drivers with shifted poles/magnets if anyone has some that are destined for the landfill.:)

http://www.polkaudio.com/forums/showthread.php?t=87460

[nooshinjohn]

will dipping the magnets up to the bottom of the basket in some sort of plastic resin or that material used to make rubberized grips for tools work for this purpose?

[tx_polkhead]

will dipping the magnets up to the bottom of the basket in some sort of plastic resin or that material used to make rubberized grips for tools work for this purpose?

I doubt the rubber grip material will have the same kind of HOLD that true addhesive will have, also the dip will give the entire magnet structure a blanket not sure that's a good idea...

[ben62670]

Guys most of the original MW were not riveted. I have had about 10 drivers damaged in shipping.
http://www.polkaudio.com/forums/showpost.php?p=654292&postcount=141
Nearly none of these were riveted.

Epoxy may work. I have used high heat hot glue.

[zarrdoss]

You can easily tell if they are riveted, just shine a AA mag light into the spider in a darkened room and you will see the rivets through the spider