Adhesive choices. - UK Vintage Radio Repair and Restoration Discussion Forum

Nanozeugma · 19th May 2023, 3:46 pm

Hi.

What would be considered the best choice of adhesive to use in attaching a new loudspeaker fabric to a wooden baffle board?

I was thinking an impact adhesive in order to stop it relaxing and losing tension while setting...

It does, of course need to end up taut and straight (ideally

)

Thanks in advance.

The Philpott · 19th May 2023, 3:51 pm

Would that dry too quickly though? Not sure.
Dave

Vintage_RC · 19th May 2023, 5:55 pm

Would the material water shrink? If so a spray with a water mist might be a way to tighten it.

vinrads · 19th May 2023, 7:32 pm

I used to use the spray carpet glue not sure if it's the make but I have noticed on certain jobs it seems to be letting go , I now use Bostic in a tube a lot cheaper than a tin of Evo-Stik which goes hard in the tin after a while even when the lid is on. Mick.

kalee20 · 19th May 2023, 10:12 pm

I'd try a spray adhesive on the baffle board, and lay the baffle down on a flat surface covered with slightly stretched fabric. Press down, allow to set, then turn over and staple around the edges with a staple gun.

G6Tanuki · 20th May 2023, 2:49 pm

Remember that many speaker fabrics are designed to shrink slightly when heated, meaning that a quick waft with a hairdryer once the glue has hardened will remove any wrinkles and leave the fabric nice and taut.

As to the best glue, I used to use Copydex, the White stuff beloved of craft type people.

Is it still available I wonder

ajgriff · 20th May 2023, 9:47 pm

Copydex is still made and is readily available but I've no idea whether or not the formulation is still the same.

Alan

Nanozeugma · 21st May 2023, 3:53 pm

Thanks for your input folks.
I used Copydex in the end.
Dries quite quickly and grips like iron once set.

It is (of course) still readily available, and as far as my nose is concerned, the formula is unchanged - it still stinks!

JohnBG8JMB · 24th May 2023, 2:36 pm

SORRY IF THIS IS TOO LATE...
Do NOT use copydex - it is a rubber latex base and has a short life. convenient for a quick stick but not for anything you want to last more than a couple of years

John

Nanozeugma · 24th May 2023, 3:59 pm

Quote:

Originally Posted by JohnBG8JMB

SORRY IF THIS IS TOO LATE...
Do NOT use copydex - it is a rubber latex base and has a short life. convenient for a quick stick but not for anything you want to last more than a couple of years

John

Noted.
Time will tell.
The baffle board in question is from a 1930's Murphy radio.
It is separate from the cabinet and screwed in place.
The glue only tacks the fabric around the border of the board.
It is then screwed back into the cabinet once set.
I doubt it would move, even if the glue did deteriorate...

emeritus · 25th May 2023, 6:06 pm

Short life was my experience the last time I used Copydex to join pieces of fitted carpet using heavy webbing. I would use solvent-based Evostik. Wooden stuff I glued with Evostik more than 30 years ago, and some paperback books whose spines I re-glued more than 50 years ago, are still sound, I just hope they don't go and change the formulation.

agardiner · 26th May 2023, 6:59 pm

I have tried various glues including spray carpet glue, copydex, PVA etc.

Last year I came across 'Mod Podge' which the wife bought for some craft projects. I gave it a go on speaker cloth and have never looked back. I would not use anything else now. I use a paint brush to apply to the baffle and then apply the cloth; stretch taught and clamp. I use lots of little craft clamps which are almost like plastic bulldog clips. Use the Mod Podge sparingly, it works really well and you don't want it bleeding through the fabric.

It is available in many craft type stores and places like the Range.

Boulevardier · 26th May 2023, 8:33 pm

Something I've often pondered - surely speaker fabric is by it's nature fairly permeable. So, if you apply clamps to the fabric while glue is curing, don't you end up with clamps stuck to the workpiece?
Mike

agardiner · 26th May 2023, 9:01 pm

I certainly haven't had this as a problem. My clamps are small plastic craft clamps. I use lots around the edge of the fabric. I don't use them to hold the fabric on the glue so to speak, but to keep it taught while drying.

emeritus · 26th May 2023, 9:27 pm

I use the backing paper from sheets of Avery self-adhesive labels to stop glue sticking where it is not wanted when clamping-up. They seem to have some sort of silicone layer on the label side that nothing will stick to (not even the lables after they have been pulled off).

Boulevardier · 26th May 2023, 9:31 pm

Quote:

Originally Posted by emeritus

I use the backing paper from sheets of Avery self-adhesive labels to stop glue sticking where it is not wanted when clamping-up. They seem to have some sort of silicone layer on the label side that nothing will stick to (not even the lables after they have been pulled off).

Thanks. Very useful tip for general use of glue.
Mike

The Philpott · 13th Jun 2023, 3:37 pm

-My other half's hairdryer came apart last night, the bristly bit is hard plastic and the handle soft plastic.....Hmm!

I chose hot-melt as the best chance for success, and what did impress me was it's superb gap filling properties on a rather loose fitting handle. You have to work quickly, and if i did it again i would probably pre-warm the workpiece, but so far so good. I've also sent a recessed screw through the handle at 45 degrees, but even without this i think it would have been fine.

Dave

19th May 2023, 3:46 pm	#1
Nanozeugma Heptode Join Date: Nov 2017 Location: London, UK. Bury, Lancashire quite regularly :) Posts: 611	Adhesive choices. Hi. What would be considered the best choice of adhesive to use in attaching a new loudspeaker fabric to a wooden baffle board? I was thinking an impact adhesive in order to stop it relaxing and losing tension while setting... It does, of course need to end up taut and straight (ideally ) Thanks in advance. __________________ Thermionic Emission, warms the cockles of your tubes.

19th May 2023, 3:51 pm	#2
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,106	Re: Adhesive choices. Would that dry too quickly though? Not sure. Dave

19th May 2023, 5:55 pm	#3
Vintage_RC Heptode Join Date: Sep 2018 Location: Twickenham, London, UK. Posts: 538	Re: Adhesive choices. Would the material water shrink? If so a spray with a water mist might be a way to tighten it. __________________ Alan G6PUB, BVWS

19th May 2023, 7:32 pm	#4
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,761	Re: Adhesive choices. I used to use the spray carpet glue not sure if it's the make but I have noticed on certain jobs it seems to be letting go , I now use Bostic in a tube a lot cheaper than a tin of Evo-Stik which goes hard in the tin after a while even when the lid is on. Mick.

19th May 2023, 10:12 pm	#5
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,081	Re: Adhesive choices. I'd try a spray adhesive on the baffle board, and lay the baffle down on a flat surface covered with slightly stretched fabric. Press down, allow to set, then turn over and staple around the edges with a staple gun.

20th May 2023, 2:49 pm	#6
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,998	Re: Adhesive choices. Remember that many speaker fabrics are designed to shrink slightly when heated, meaning that a quick waft with a hairdryer once the glue has hardened will remove any wrinkles and leave the fabric nice and taut. As to the best glue, I used to use Copydex, the White stuff beloved of craft type people. Is it still available I wonder __________________ I'm the Operator of my Pocket Calculator. -Kraftwerk.

20th May 2023, 9:47 pm	#7
ajgriff Nonode Join Date: May 2004 Location: Halifax, West Yorkshire, UK. Posts: 2,587	Re: Adhesive choices. Copydex is still made and is readily available but I've no idea whether or not the formulation is still the same. Alan

21st May 2023, 3:53 pm	#8
Nanozeugma Heptode Join Date: Nov 2017 Location: London, UK. Bury, Lancashire quite regularly :) Posts: 611	Re: Adhesive choices. Thanks for your input folks. I used Copydex in the end. Dries quite quickly and grips like iron once set. It is (of course) still readily available, and as far as my nose is concerned, the formula is unchanged - it still stinks! __________________ Thermionic Emission, warms the cockles of your tubes.

24th May 2023, 2:36 pm	#9
JohnBG8JMB Pentode Join Date: May 2006 Location: Poole, Dorset, UK. Posts: 130	Re: Adhesive choices. SORRY IF THIS IS TOO LATE... Do NOT use copydex - it is a rubber latex base and has a short life. convenient for a quick stick but not for anything you want to last more than a couple of years John

25th May 2023, 6:06 pm	#11
emeritus Dekatron Join Date: Jan 2012 Location: Brentwood, Essex, UK. Posts: 5,339	Re: Adhesive choices. Short life was my experience the last time I used Copydex to join pieces of fitted carpet using heavy webbing. I would use solvent-based Evostik. Wooden stuff I glued with Evostik more than 30 years ago, and some paperback books whose spines I re-glued more than 50 years ago, are still sound, I just hope they don't go and change the formulation.

26th May 2023, 6:59 pm	#12
agardiner Octode Join Date: Sep 2020 Location: Thetford, Norfolk, UK. Posts: 1,741	Re: Adhesive choices. I have tried various glues including spray carpet glue, copydex, PVA etc. Last year I came across 'Mod Podge' which the wife bought for some craft projects. I gave it a go on speaker cloth and have never looked back. I would not use anything else now. I use a paint brush to apply to the baffle and then apply the cloth; stretch taught and clamp. I use lots of little craft clamps which are almost like plastic bulldog clips. Use the Mod Podge sparingly, it works really well and you don't want it bleeding through the fabric. It is available in many craft type stores and places like the Range.

26th May 2023, 8:33 pm	#13
Boulevardier Octode Join Date: Sep 2017 Location: Bristol, UK. Posts: 1,654	Re: Adhesive choices. Something I've often pondered - surely speaker fabric is by it's nature fairly permeable. So, if you apply clamps to the fabric while glue is curing, don't you end up with clamps stuck to the workpiece? Mike

26th May 2023, 9:01 pm	#14
agardiner Octode Join Date: Sep 2020 Location: Thetford, Norfolk, UK. Posts: 1,741	Re: Adhesive choices. I certainly haven't had this as a problem. My clamps are small plastic craft clamps. I use lots around the edge of the fabric. I don't use them to hold the fabric on the glue so to speak, but to keep it taught while drying.

26th May 2023, 9:27 pm	#15
emeritus Dekatron Join Date: Jan 2012 Location: Brentwood, Essex, UK. Posts: 5,339	Re: Adhesive choices. I use the backing paper from sheets of Avery self-adhesive labels to stop glue sticking where it is not wanted when clamping-up. They seem to have some sort of silicone layer on the label side that nothing will stick to (not even the lables after they have been pulled off). Last edited by emeritus; 26th May 2023 at 9:29 pm. Reason: typos

13th Jun 2023, 3:37 pm	#17
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,106	Re: Adhesive choices. -My other half's hairdryer came apart last night, the bristly bit is hard plastic and the handle soft plastic.....Hmm! I chose hot-melt as the best chance for success, and what did impress me was it's superb gap filling properties on a rather loose fitting handle. You have to work quickly, and if i did it again i would probably pre-warm the workpiece, but so far so good. I've also sent a recessed screw through the handle at 45 degrees, but even without this i think it would have been fine. Dave