View Full Version : 2441 diaphragm repair

05-16-2018, 04:19 AM
This weekend I picked up some NOS 2441 diaphragms, 2440/2441 drivers and BGW 750s. The seller threw in this diaphragm for free because he had damaged it, he said he thinks he dropped it. Is there any way to repair this so itís in a usable condition? Itís never been used, it was damaged when taking out of the packaging.

From the photos you can see that it is not a perfect circle, the circular paper has been dented and bent in slightly. The coil looks okay, and there is a small dent in the middle. It seems a shame to just throw it away, is there any way it can be revived?

Earl K
05-16-2018, 05:17 AM
Well, that diaphragm is too valuable to simply toss just because one doesn't know ( at this juncture in time ) how to bring the coil back to "round".

At the very least, put it on a shelf while the "how-to-fix-it" fairy makes her way into your brain ( "idea-percolation", etc, etc. ).

FYI, I'm confident that some metal ( skilled tool & die ) worker would be able to bring that coil back to "round" with proper care & effort.

If I was to try a fix I would search out ( & procure ) something very close to the inside diameter of the coil ( which I think is just under 4" ) to use as a clamped back-stop ( anvil press ) to reform the coil onto ( by applying physical pressure to the mis-shapened outside of the coil ) .

A metalworking tool known as the "Surfacing Spoon" (https://www.google.ca/search?q=surfacing+spoon&rlz=1C1CHBF_enCA703CA703&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiltLOCmIrbAhURjlkKHY5mDakQsAQIKA&biw=1264&bih=681#imgrc=_) ( used in reverse if that surface is a smooth arc ) looks to be the "go-to" implement of choice.


PS; Something to keep in mind, the gaps of the 2482 driver ( and I think the 2445 and later models ) are slightly wider ( and may accommodate a "fixed" coil somewhat better ).

05-16-2018, 11:00 AM
I have one Iíll sell.

05-17-2018, 07:10 AM
At the very least, put it on a shelf while the "how-to-fix-it" fairy makes her way into your brain ( "idea-percolation", etc, etc. ).

That was probably what I was going to do, but your advice is appreciated! It all sounds like a bit much for me, I'd be worried I would damage it more by trying to bend it back. Perhaps best to sell it to someone who thinks they can fix it? I have no need for it, its a spare diaphragm, and I was told that its very hard to actually destroy the 2 inch diaphragms if they are set up correctly.