Screws getting loose on a driver and one damaged thread

GUYS,
Last weekend I used an old pair of LS608's
One was doing a rumbling sound at medium power level, so removed the front cover and found all of the screws loose, some more than others, idk if they are wood screws or metal ones , I guess wood cause one did not want to get tight, the wood hole just give up.

What I can do to prevent the screws from getting loose, or that is normal and you need to open your subs from time to time and check any loose screws?


Also how to "repair" a damaged wood hole so the screw can hold tight again.

Best.
Max.
 
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Joined 2011
Paint or hot glue on the screw head can help keep the wood screw from loosening due to vibration.
It's kind of normal for them to get loose after a while.

The oldest trick for a stripped hole is to stick a toothpick or two partly through the hole beside the loose wood screw,
and then carefully tighten it. That will use up the extra space. Then break off the part sticking out by the screw head.

A better fix is to rotate the driver enough so solid wood is under the driver mounting holes (seal up the old holes first
with mortite or wood putty). I would drill small holes in the right places first, so you can get the wood screws started easily without the screwdriver slipping and going through the cone.
 
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GUYS,
Last weekend I used an old pair of LS608's
One was doing a rumbling sound at medium power level, so removed the front cover and found all of the screws loose, some more than others, idk if they are wood screws or metal ones , I guess wood cause one did not want to get tight, the wood hole just give up.

What I can do to prevent the screws from getting loose, or that is normal and you need to open your subs from time to time and check any loose screws?


Also how to "repair" a damaged wood hole so the screw can hold tight again.

Best.
Max.

I haven't personally had screws come loose from normal use, though if the cabinets are moved often as in a mobile DJ, this may be an issue. To fix a hole, you can use a few birch toothpicks in the hole and a bit of cyanoacrylate glue. Break off the toothpicks once they are glued in and run in the screw by hand before mounting the driver.

Remove screw, cut off any extra material with a sharp knife, and install the driver. You may be able to use larger diameter screws, provided they fit the basket recess. I have used metal screws typically in the past, they have thread all the way to the head.

You could instead re-clock the driver and drill new holes equal to the root diameter of the screw.
 
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I know some people like to use the metric metal screws that have the nut with spikes so the nut are stuck firm in to the wood, the metal ones are more resilient to strip off than regular wood screws on a wooden hole.

IDK if I can swap the wood screws for the metric metal spiked nut types, the cabinets are kind of the CUBO (quasi horn hybrid) type , I guess I can't reach my hand to the back chamber to install the T-nuts(spike nuts).

Anyway, those are kind of kick bins, don't got lower than 50Hz, by today standards that Su... Big time.
Nowdays people love 30hz PA cabs, I guess the car audio virus have envolved to infect the PA community and mutate them in to bassheadz!! Lol. 😂
 
I know some people like to use the metric metal screws that have the nut with spikes so the nut are stuck firm in to the wood, the metal ones are more resilient to strip off than regular wood screws on a wooden hole.

IDK if I can swap the wood screws for the metric metal spiked nut types, the cabinets are kind of the CUBO (quasi horn hybrid) type , I guess I can't reach my hand to the back chamber to install the T-nuts(spike nuts).

Anyway, those are kind of kick bins, don't got lower than 50Hz, by today standards that Su... Big time.
Nowadays people love 30hz PA cabs, I guess the car audio virus have envolved to infect the PA community in to bassheadz!! Lol
 
You could embed a long nut (hex) in the wood using strong glue and then use bolts (vs. screws) to tighten. This way the contact becomes metal-to-metal and a blue/green (not red) threadlocker maybe used. It is non-corrosive, easily washes off from the skin, is very strong (used on wheel nuts of cars) and easily available at auto spare shops.
 
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Since those cabinets are circa 2000 , I'm puzzled that the drivers don't have a broken cone , supposedly Yorkville used B&C drivers , idk what model, I was thinking on getting some 18tbx100 for them or maybe some Lavoce or PrV , idk if that makes some good or just a waste of $$$
 
Waste of money... they won't go any lower. The drivers used in these were custom from RCF or B&C similar in spec to an L18P200 or 18 TBX46, old drivers now but still very capable and there wouldn't be enough gained with newer drivers to justify the cost.
 
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If you need to re-use the same holes (rather than rotate the driver, so the holes are over fresh wood), then the T-nuts are probably the best option. Another possibility, which can be used from the front, are 'threaded inserts' - look at the ones designed for wood (there are versions for metal., plastic etc too).
ae235

They have a big wood thread on the male/outside, and a machine screw (bolt) type thread on the female/inside. Edit: check if their extra size would be okay though, some driver holes are big enough to be very close to the screws.
 
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Speaker nuts is the local name for T-nuts here...
There is a large selection in automobile use for bolts, if you have the drive bits.

I would also try to see the condition of the speaker enclosure, sometimes chipboard starts disintegrating.
Use felt washers or similar to reduce vibration transfer to the cabinet from the driver.
 
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Maxolini, Philips do not suck, they have a purpose.
Allan head screws are almost non existent depending on where you live
Robertson are the choice of many for a number of reasons.
T-nuts, hurricane nuts and threaded inserts are usually unnecessary for your use.
Hole fillers, starting with toothpicks and PVA glue and working up to the plastic expanding sleeves are your best bet from what I have read in your posts.
If you choose the simple yet effective toothpick method, make sure you lay the speaker on its back and tape off the back of the hole before adding the glue and toothpicks. Use yellow glue if you have it and leave it for a good 20 minutes before installing the screws.
I have never had one of these back out.
It is also stronger than drilling new holes. The woodworkers and MacGyvers out there will get it.
 
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