I'm going to try my hand at repairing a MW6511. I recently bought a set of SDA-1c's and the right speaker ended up having a blown driver. After looking into a replacement, I was disappointed to find out the new replacements aren't held in the same light as the older ones. After posting my trials and tribulations on CP, I lucked out when a fellow CP member dug one out of storage and sent it to me. Even though he went the extra mile by packing the unit in tons of bubble wrap, the apes at UPS managed to break the magnet loose and bend the driver cage.
The driver was making a scratching noise at lower volume. Further investigation revealed the magnet had indeed shifted. I went to work trying to find anything I could about repairing this type of damage. I read and re-read a posts on how to re-attach magnets. One very good thread suggested using 3 screwdrivers and slowly pry apart each side of the magnet. I followed this person's lead and used shims to help separate the magnet from the basket. I really had to work to get them separated. Once apart, I could easily see where the epoxy had become brittle over all the years this speaker has been awaiting it purpose.
The other side of the magnet was still attached, but I figured if I'm going to take the time to attempt a repair I might as well do the entire thing. I used a dead-blow hammer to break this apart. I then pushed the cone forward and covered the voice coil with tape. I don't want to get anything in the space, as that would render the entire project useless at that point.
Once the voice coil was covered, I scraped away all the old epoxy. It was stuck on really well and took quite a bit of effort to remove. I used the same blue tape to remove all the little pieces then wiped the entire thing down with alcohol. I paid close attention to the piece which guided the voice coil. I cleaned it thoroughly and made sure to wipe it with alcohol as well.
Once the magnets, basket, and the rear piece were scraped and wiped down with alcohol I used some JB weld to re-attach the magnet to the rear piece. I made certain to not use too much where it may seep back and interfere with the movement of the voice coil.
I am done for tonight. I cannot do any more work until the JB Weld sets up. I did go ahead and make a jig to help set the magnet so there's no interference and the voice coil doesn't rub. I'm hoping to make it to the end of this adventure without messing anything up. If anyone has suggestions or some advice, I will gladly accept it. I can provide my contact info for anyone who would like to speak rather than do this back and forth on a message board. PM me and I'll do my best to accommodate your schedule.
Thanks for the inspiration... One way or the other I will get these SDA's back in play!!!