I'm hoping someone can help out a JBL noob here. I have a pair of L100s, and the mounting screws on one woofer seem to be stripped--or else they're seized up in the anchors, and it's the anchors that are turning in the cab. I think it's probably the latter. Any suggestions on how to get at these so I can pull the woofer? Any and all advice would be greatly appreciated.
Usually its the t-nut spinning loose. If you can get the other screws out, try gently prying up the speaker flange while turning the screw.
Unfortunately, none of them will come out. They're all doing the same thing. It's as if they were put in with Loctite or something.Originally Posted by rdgrimes
That's some pretty old MDF, and the t-nuts routinely come loose. that doesn't rule out some nitwit putting loctite on the threads some years ago, or they are just rusted.
Worst case you remove the mid or tweeter and go in that way to grab them. You may have to knock loose the isolation can behind either one of those. Patience is a virtue in this situation. Plan on needing new t-nuts when its all done.
if you drill the center of each bolt with a series of increasing size bits ( 1/8 to 3/16 ) the head will simply break off from the shaft. The depth is just a little deeper than the bottom of the "+"
You can jam a very small finishing nail in between the head and speaker frame if needed.
use a shop vac to suck away the metal shavings while drilling.
Most often the bolt ( and/or ) t-nut is corroded.
been there many times...it's always the consumer models that have this issue...wonder why..??
It's been a while since I was working on them and ran into the problem. But if I recall correctly, I pulled the mid and there was some kind of port tube or something behind it. The idea at the time was to try and get hold of the back end of it with a vise grips or something. But the way they're made (with the port tube or whatever it was) meant it wasn't simply a matter of displacing some insulation. I'll have to pull it again to check, but that's about where the process stalled the last time I messed with them.
Have you really had to do this before?
Argh! That's kind of what I was hoping I wouldn't need to do.
You might try pushing in the plate on the back that the terminals are fastened to. Just push it into the cabinet by tapping with the handle of a hammer. It's usually held in place by a few staples. It's behind the woofer, and the hole is a bit bigger than the tweeter hole. You will have to use a few screws to put it back in place later.
I recently had this problem with 2206h in a cab- removed the non-spinning screws (only one had come loose) and had to leverage the driver and cut the bolt out with a hacksaw.
Big fun!
But fortunately only minor damage to the replaceable cabinet, driver's fine.
Part of the trouble is that you sometimes have to push in hard on the screwdiver while turning to keep the tip from slipping in the screw, but pushing on the screw while turning also tends to push the T nut out of the back of the baffle. Prying up on the woofer while trying to remove the screw can help in this case. Too bad that woofer is often stuck to the baffle and can't be pried up. It's a struggle many of us have been through.
home depot has a small blue thin metal prybar that can be "tapped" under the frame where the problem screw(s) are....this might do the trick - and the most important thing about these restorations is use NEW, high quality screwdrivers with the right tip size!
Those cheapo wonder sets or anything you've had for years is useless for this app....
BTW - look at the next post to see EXACTLY what a dull phillips screwdriver does to a speaker...!
http://www.audioheritage.org/vbullet...eed-some-care-!
absolutely correct ..take out all the screws that you can , break the woofer loose by laying on its face, pick up one edge 4-5 inches and let drop (do on carpet) ....when some have come out, you can lift that area ..putting pressure on the stuck one, securing it so no T-nut turn and then try to back out the screw.
worst case ...drill out the screw head or grind off.
Some kind of happiness is measured out in miles
LOL, I made that very same mistake once.......home depot has a small blue thin metal prybar that can be "tapped" under the frame where the problem screw(s) are....this might do the trick - and the most important thing about these restorations is use NEW, high quality screwdrivers with the right tip size!
Those cheapo wonder sets or anything you've had for years is useless for this app....
BTW - look at the next post to see EXACTLY what a dull phillips screwdriver does to a speaker...!
http://www.audioheritage.org/vbullet...eed-some-care-!
Go get a Dremel moto-tool and grind the heads off those screws right now -
don't gamble - why risk punching out your cones with a screwdriver or anything less.
2ch: WiiM Pro; Topping E30 II DAC; Oppo, Acurus RL-11, Acurus A200, JBL Dynamics Project - Offline: L212-TwinStack, VonSchweikert VR-4
7: TIVO, Oppo BDP103D, B&K, 2pr UREI 809A, TF600, JBL B460
That may be what I'll end up doing. I actually have a Dremel 3000 kit that was just given to me as a gift, and I haven't even tried it out yet. This may just be it's initiation!
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