General Forum

Re: Refoaming cx100

riis — Sun, 07 Feb 2010 16:27:47 GMT

Thanks Chris, now I understand.

/riis

Re: Refoaming cx100

Medogsfat — Sun, 07 Feb 2010 15:56:32 GMT

Apply glue to edge of the new surrounds, reverse the polarity of the battery & the cone will move outwards which will ensure the coil is centred. Then swap back the polarity of the battery & it will move inwards, now you can safely weigh it down with a suitably sized ring, disconnect the battery & leave to set.

Chris.

Re: Refoaming cx100

riis — Sun, 07 Feb 2010 15:34:19 GMT

Medogsfat:

Like Mika I also use the battery method the centre the coil, and ALWAYS start by gluing the inner ring to the cone or you'll never get them centred properly. Find a glass tumbler or similar which will sit inside the inner ring of the surround to weight it down to the cone until the glue sets.

Chris.

I really don't know how the battery method works. I've tried to connect a 1.5 v battery to the speaker and the cone moves inwards. How can that help me to center the cone?

/riis

Re: Refoaming cx100

Medogsfat — Fri, 05 Feb 2010 14:39:48 GMT

riis:

BTW what's the difference between the two drivers in the cx 100? They have different numbers?

One is a full range unit (the one with the hole in the back) to provide mid range & the other is a bass driver. B&O now only supply the full range one as a replacement for both.

Like Mika I also use the battery method the centre the coil, and ALWAYS start by gluing the inner ring to the cone or you'll never get them centred properly. Find a glass tumbler or similar which will sit inside the inner ring of the surround to weight it down to the cone until the glue sets.

Chris.

Re: Refoaming cx100

stotty1111 — Fri, 05 Feb 2010 05:32:21 GMT

good luck should have added i started with the inner ring sticking wise - easier to apply the glue whilst away from the unit and also easier with the outer then pull it down with the battery method - i used a birds custard red plastic lid on the outer with some added weight to improve adherance, wine glass of appropriate diam on inner ring!

hope this helps

Re: Refoaming cx100

riis — Tue, 02 Feb 2010 15:27:03 GMT

The methylated spirit works fine. I have cleaned the first driver. Only three more to go?

BTW what's the difference between the two drivers in the cx 100? They have different numbers?

Re: Refoaming cx100

tournedos — Tue, 02 Feb 2010 04:03:29 GMT

The battery trick helps as well - connect a 1.5V battery to the driver. First to push the cone outwards so it'll be easier to apply the glue, then to pull it inwards which helps to center the cone. I used this with the method from the Good Hifi manual with good success, although I had to redo one of the six drivers from my CX50+100 project (check for scraping before the glue sets completely so you can still pull the outer edge off and try again).

The cardboard shell of a Bowmore bottle can be cut into rings that are the perfect size for weighing down the outer rim

Re: Refoaming cx100

wirralsimon — Mon, 01 Feb 2010 18:35:39 GMT

I used lots of clothes pegs to hold the outside of the foam in place after adding the glue and then adjusted the position until I couldn't hear any scraping sounds when I pushed the driver in and out in and out. There may be better methods though!

Simon

Re: Refoaming cx100

riis — Mon, 01 Feb 2010 16:13:45 GMT

wirralsimon:

I removed as much glue as I could without damaging the woofers by scraping using a craft knife blade, and them wiped with methylated spirit.

I then glued the new foam ring directly on to the remains of the other glue and it worked fine.

Simon

The trick with methylated spirit works fine although it takes some time to get all the way round. I'm glad the woofers are not 15". How did you solve the problem with centering the cone? Did you use shims?

/riis

Re: Refoaming cx100

wirralsimon — Mon, 01 Feb 2010 03:58:18 GMT

I removed as much glue as I could without damaging the woofers by scraping using a craft knife blade, and them wiped with methylated spirit.

I then glued the new foam ring directly on to the remains of the other glue and it worked fine.

Simon

Re: Refoaming cx100

stotty1111 — Mon, 01 Feb 2010 03:13:30 GMT

try soaking the foam ring with methylated spirit applied using a small(artists) paint brush - leave for about 5 mins to soak in / soften the glue then carefully use an old blade ie not too sharp - when ring off clean up cone with a little more meths /scraping leave overnight for the meths to evaporate as it also tends to soften the cone material(personal experience) then refoam as normal??

cheers

tony s

Refoaming cx100

riis — Mon, 01 Feb 2010 01:23:38 GMT

I have refoamed a couple of speakers with no problems, but have a problem with my current project. The cx100 woofers seems to be a little tricky. I have removed most of the foam ring, but the foam which is glued to the paper cone is tricky. Has anybody got a solution how to take it away? Or do you just glue the new foam ring on top of it? The speakers I have refoamed before didn't cause any problems. It was easy to remove the old foam on the paper cone.

/riis