Club 80-90 Forums

Whilst fitting my new speakers I slipped and stuck the screwdriver through one of the cones.
What an idiot,
Please refrain from confirmin that.
Any ideas what to do to minimise the pain would be gratefully recieved, Its only a small tear but it did go through.
As they are £80 to replace I want to fix these.
Its right on the edge of the centre dome.
Rob.

Stick something like masking tape over the tear to stop it getting worse. The rest of the speaker should be able to flex normally, and in a van situation you might not be able to tell! Try it and see...

I'm assuming it is just the cone that is torn, and that you've not gone and damaged the coil in the middle?

if the cones are good quality ie not crappy paper a small patch of fiber glass tissue might do, nice and strong dont know if it will affect the sound to much others might be able to answer that.

if the cones are good quality ie not crappy paper

Paper cones are not all crappy, many excellent Hi-Fi speakers had paper cones, as they are 'doped' to produce a controlled breakup as frequences rise and in many respects layeredpaper has excellent characteristics - self-damping - rant-over about misconceptions - horses for courses.

Depending what the cone material is, and what the size and frequ range of the driver is ??? (this is Tech Advice, right?)

and you can get at it, try to repair with similar, but keep it thin...
Paper, if the edges go back together, then some latex glue (be sparing else you'll upset the cone's breakup mode), with a little reinforcement, something like tissue paper, crinkle it up first and then flatten it back, maybe puff some fine water mist over it on a dry day first, and do both sides if you can get at them

If there's a clear hole with missing material, pull it back together as much as possible and try soaking some egg-box cardboard like paper mache, thin, don't hack it all a round, water down the latex first, not the heavy stuff carpet fitters use without thinning. Put backing tissue on one side, then a little mache, then finish the other isde with a laminate of tissue paper

If the cone is Butyl, Vinyl, or a composite laminate of synthetics, then mayeb you could try a RTV silicone? Again keep everything thin, don't plaster too much about unless looks like it needs it..
If you have any rubber glue, that might prove strong enough too

Im not really sure waht they are made of.
If I had to guess I would say some sort of paper wire composite.
It was like a weave of speaker wire coated in paper, a bit like concrete reinforcement.
I was thinking of the stuff they use to seal the wires coming through on a multi range speaker, some sort of liquid rubber?
They are Alpine SXS 1757 components, if that helps at all.
What a plonker though.
Rob.........

Don't rule out the paper-mache technique either (if they ARE paper). Done that myself and it works well.

HarryMann wrote:

if the cones are good quality ie not crappy paper

Paper cones are not all crappy, many excellent Hi-Fi speakers had paper cones, as they are 'doped' to produce a controlled breakup as frequences rise and in many respects layeredpaper has excellent characteristics - self-damping - rant-over about misconceptions - horses for courses.

Yeah to reiterate that point, nearly all professional drive units (speaker cone) are made of paper. The best speakers money can buy are probably L-acoustics, EV or Nexo speakers and they all use paper cones for their bass drivers.

It was like a weave of speaker wire coated in paper, a bit like concrete reinforcement.

I know the stuff of which you speak, but not technially what it really is. It's very much like that gloop that is used these days to stick things on surfaces, but can be removed, like those Spot-It lights, and like the stuff used to stick glossy (annoying) adverts into magazines maybe? A coarse polypropylene therad weave covered in that gloop ?

1) You don't want oil/grease around the area, so wash your hands well first with soap.

2) I'd work along the lines of silicone, like RTV, but it must be fresh as a fresh thing, no stodgy bits... and build up in thin layers, use vinyl gloves to smear and glue the area back together, let it dry according to instructions, prob. 24 hrs and build-up a bit more if mecessary. See if you can find what the solvent is if any for RTV.

3) If you have made a hole not a split, then you'll need something like thin but stiff plastic sheet. Polythene might work, but test to see if the adhesive sealant will stick it first.

Only do the next one if you end up doing it on April 1st:-

4) Then make 2 more identical splits, equi-angular, so you have three at 120 degree intervals to keep the symmetry, and fix 'em too - else the coil might rub at full chat....

Cheers Harryman i think the RTV is the way to go thanks for all your advise.
Rob.

A bicycle repair patch has worked for me in the past.

A bicycle repair patch has worked for me in the past.

Now that's a good idea, those thin ones that are chamfered off to a fine edge, if you can find one big enough, go for it, on that type of cone.