Retrovert
Addicted Member
Don't be using that as an excuse to be huffing that toluene. You get caught and they won't let you go up on stage for graduation.
Using Latex Cement for KLH Cloth Surround Doping
- Thread starter KingBubba
- Start date
Don't be using that as an excuse to be huffing that toluene. You get caught and they won't let you go up on stage for graduation.
Pio1980
AK Member
Seriously, I got a pair of AR 4x for $12 at a flea mkt mebbe 25 years ago and didn't get around to redoping them along with doing refurb. They are still on my to-do list and not going anywhere.
teebee
Well-Known Member
If you want to roll your own CORRECT stuff, dissolve butyl seam tape in toluene or 2nd: xylene.
Thinned butyl is the only stuff that should be used per KLH, and it seems that the only suitable carrier solvent is toluene with a distant second being xylene.
The supplies for the correct sealant are quite hard to find nowadays.
The result is very stinky, very tacky, and dries fairly quickly. NASTY stuff that if it dries on your hands, Is very mechanically stubborn. If you end up mixing it thin, you’ll just need to more than one coat. I redoped my Fours, Seventeens, and a friend’s Twenty Fours with just a few ounces.
I used only the correct butyl juice.
I do recommend the pricy AR stuff, however.
Thinned butyl is the only stuff that should be used per KLH, and it seems that the only suitable carrier solvent is toluene with a distant second being xylene.
The supplies for the correct sealant are quite hard to find nowadays.
The result is very stinky, very tacky, and dries fairly quickly. NASTY stuff that if it dries on your hands, Is very mechanically stubborn. If you end up mixing it thin, you’ll just need to more than one coat. I redoped my Fours, Seventeens, and a friend’s Twenty Fours with just a few ounces.
I used only the correct butyl juice.
I do recommend the pricy AR stuff, however.
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Retrovert
Addicted Member
Not all roofing seam tape (aka flashing tape) is butylene rubber.
Some (much?) of it is a blend of butyl on an EPDM (ethylene propylene diene monomer rubber) rubber base. This is far more durable. I had looked into this some time ago for sound deadening and discovered a range of materials. The butylene layer is to make it sticky and viscoelastic so it survives heating/cooling cycles without leaks.
Xylene, FWIW, is not much different than toluene. Xylene has one more methyl group, so it's a little less volatile. Toluene is readily available in most hardware stores.
Some (much?) of it is a blend of butyl on an EPDM (ethylene propylene diene monomer rubber) rubber base. This is far more durable. I had looked into this some time ago for sound deadening and discovered a range of materials. The butylene layer is to make it sticky and viscoelastic so it survives heating/cooling cycles without leaks.
Xylene, FWIW, is not much different than toluene. Xylene has one more methyl group, so it's a little less volatile. Toluene is readily available in most hardware stores.
Yeah, I totally agree, which is why I'm sending you plaudits.
Yes, I know all about CSP - - I'm sort of a regular there - - but I'm just pointing out that the excellent 3a-resto document has a few areas that could benefit from updated revisions and additional details before anybody sends someone else to rely on this section of the document for full accuracy.
While there may be only two primary ingredients in this elixir, the process for combining them remains undocumented.
Yep, toluene is toxic stuff, as are many solvents available from the hardware store that need to be handled with utmost care. And I'm not talking about about some "company" brewing this stuff - - I'm just pointing out that several AK-ers have claimed that this is an easy-peasy concoction without any proof - - it seems that teebee in post #103 just might be the first to claim to have performed the laboratory chemistry.
Please show and tell us more if you can.
Retrovert
Addicted Member
The KLH documentation makes it clear it is butylene rubber dissolved in a solvent. Others have talked about making it. It's not hard to dissolve natural rubber in a solvent.
I hve reconstituted rubber cement this way because the jar was congealed (my sealed backup jar, too) and I was under time pressure to finish a job and lacked the time to do a hardware store run even if one was still open. Rubber cement is natural rubber (latex) plus some neoprene, with a solvent blend of things like toluene, xylene, some acetone. Just add the solvent and agitate. I used a roofing nail to mix it together and agitated the bottle.
Always do this with adequate ventilation. Outdoors is better. Same goes for application. Just wanted to note that.
Not my point. Sure, hardware stores have all sorts of dangerous things. The problem occurs when one creates a product, notably without an MSDS or proper filings, and then starts selling it without liability insurance.
Something is wrong with the CSP webserver.
The pages are taking several minutes apiece to load; slower than with a 56k modem, and images won't load. It's not my network connection since everything else, including AK, is running at 100 Mb download. Can't see proper layout either. At least its running to some extent.
Here's some reading I was able to dig out. We good?
#1
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/8911-solvent-question/
Toluene is the solvent used in the sealant and works best to thin or reconstitute it. Xylene is second best and will work for thinning, but I'm not sure about reconstituting it from a dried state. Vintage AR was using bottles with inadequate caps (relative to the solvent) for awhile, and found they were not good for longer term storage. (I believe his new bottles are better.) I use a number of different bottles, all of which are resistant to the toluene, and had some of my first batch in them for over two years without any issues.
Toluene is the solvent used in the sealant and works best to thin or reconstitute it. Xylene is second best and will work for thinning, but I'm not sure about reconstituting it from a dried state. Vintage AR was using bottles with inadequate caps (relative to the solvent) for awhile, and found they were not good for longer term storage. (I believe his new bottles are better.) I use a number of different bottles, all of which are resistant to the toluene, and had some of my first batch in them for over two years without any issues.
#2
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/7117-cloth-surrounds/
I recently treated the surrounds of a pair of very used, and slightly porous, 2ax woofers with my butyl/toluene solution. The toluene softened the old sealant, and the surrounds turned almost black again. In the attached photo you can see the untreated areas along the edges are still orange in color. They are now nicely sealed, AND more compliant than before the treatment.
#3I recently treated the surrounds of a pair of very used, and slightly porous, 2ax woofers with my butyl/toluene solution. The toluene softened the old sealant, and the surrounds turned almost black again. In the attached photo you can see the untreated areas along the edges are still orange in color. They are now nicely sealed, AND more compliant than before the treatment.
http://www.classicspeakerpages.net/IP.Board/index.php?/topic/2538-butyl-coating-on-cloth-surrounds/
The coating we used was based on a basic Butyl Rubber compound that was Butyl Rubber sealant used by Commercial Roofers. That compound was thinned using Toluol (Toluene) to a consistency which allowed it to be applied with a paint brush. The Toluol was used rather than other thinners because of its faster evaporation characteristics.
I sourced some of the actual Butyl Rubber from my local Menards, in a caulk gun tube, and removed the contents. I mixed it with Toluol and obtained the necessary viscosity. I applied it to a couple of old drivers, from my junk supply, and it seems to work properly.
The coating we used was based on a basic Butyl Rubber compound that was Butyl Rubber sealant used by Commercial Roofers. That compound was thinned using Toluol (Toluene) to a consistency which allowed it to be applied with a paint brush. The Toluol was used rather than other thinners because of its faster evaporation characteristics.
I sourced some of the actual Butyl Rubber from my local Menards, in a caulk gun tube, and removed the contents. I mixed it with Toluol and obtained the necessary viscosity. I applied it to a couple of old drivers, from my junk supply, and it seems to work properly.
Retrovert
Addicted Member
Go to eBay. Type in "butyl rubber sheet". Add "-adhesive". Rejoice.
Go to Amazon. Type in "butyl rubber sheet". Sort by price, low to high. Rejoice.
I, for one, welcome our new butyl rubber overlords.
Tip.
Use some cloth, specifically like what klh used as a barrier between driver and fiberglass, and cut your butyl sheet into small pieces. Put your pieces onto a square of the cloth and pouch it, then twist closed with mechanics wire.
Put make shift bag into glass jar with toluene. Bag makes it possible to poke and prod and mash and squish and...
To make chunk free sealant.
Clear as mud?
Clear sealant can be made with a bunch more time involved, if you forgo the poke - squish technique.
YMMV
Use some cloth, specifically like what klh used as a barrier between driver and fiberglass, and cut your butyl sheet into small pieces. Put your pieces onto a square of the cloth and pouch it, then twist closed with mechanics wire.
Put make shift bag into glass jar with toluene. Bag makes it possible to poke and prod and mash and squish and...
To make chunk free sealant.
Clear as mud?
Clear sealant can be made with a bunch more time involved, if you forgo the poke - squish technique.
YMMV
Timely thread update.
Just scored some beautiful KLH 23.
For $20, I went with eBay vintage-ar stuff.
Not needing vast amounts, rolling my own with butyl and solvent seems silly.
How much time and energy and money will it take to roll your own!?!?!
Is anyone doing mass redoping?
Sometimes I'm amazed at the amount of time and energy and money spent in some futile effort to save a $1.
I'm all about frugal, but I don't see that here at all.
Ever since the whole "bad for you" thing got insane, the cost of chemicals that are real and work and are dangerous has gotten nuts. Protecting people too stupid to use toilet paper correctly has gotten insane.
Just scored some beautiful KLH 23.
For $20, I went with eBay vintage-ar stuff.
Not needing vast amounts, rolling my own with butyl and solvent seems silly.
How much time and energy and money will it take to roll your own!?!?!
Is anyone doing mass redoping?
Sometimes I'm amazed at the amount of time and energy and money spent in some futile effort to save a $1.
I'm all about frugal, but I don't see that here at all.
Ever since the whole "bad for you" thing got insane, the cost of chemicals that are real and work and are dangerous has gotten nuts. Protecting people too stupid to use toilet paper correctly has gotten insane.
Retrovert
Addicted Member
It's about being able to fix things and make one's own tools.
I used to be able to work on my car, now it looks like a Swiss watch under the hood, and everything requires computer diagnostics with special software, a lift, and disassembly. Mechanic no longer like working on modern cars.
But I can still rebuild HiFi gear, including a speaker.
It is always best to understand how things work.
Retrovert
Addicted Member
The black color in black butylene rubber is carbon black.
RxDx
Speaker collector
Too easy
Granted.
Just figure there isn't much call for home brew surround dope.
But, I have more things to fix than I have lifetime left.
Retrovert
Addicted Member
It's also about knowing how to reconstitute the Magick Juice when it dries out. Can't forget that part.
MrRogers385
Active Member
Hello Roy, any chance you're still producing a product to recoat cloth surrounds? I have KLH 17s and Bose 901s that could use some. Thanks. Matt
MrRogers385
Active Member
Order placed, thank you!
RTally
Speaker addict
Guitar speakers are not the same as hifi speakers. Many guitar players like to have damaged speakers because of the sound they produce. For them, their speakers are part of their instrument. HiFi speakers are reproducers. You want them to faithfully reproduce music, not flavor it. Using anything other than the good stuff (vintagear or RoyC butyl) ruins the speakers.
Retrovert
Addicted Member
That way lies destroyed speakers, misery, madness, and the ka-ching! of the cash register to replace the destroyed drivers.
NEVER USE VARNISH, GLUE, CAULK, ETC. ON A VINTAGE SPEAKER SURROUND. IT WILL DESTROY THE SPEAKER.
Here's why Corona Dope is unsuitable. The Corona Dope is a varnish (lacquer, urethane, shellac, etc.; formulations vary) intended to be painted into various windings (transformers, inductors, coils, motors, relays, etc.) and onto surfaces to avoid arcs and corona; hence the name. The ingredients are simple: varnish of various types dissolved in a mix of solvents to reduce the viscosity and surface tension, thereby permitting and inducing better flow into crevices and gaps, as well as across surfaces which would not otherwise easily wet. The solvent evaporates, the varnish crosslinks and hardens, forming an impenetrable and insulating layer. Great for coils of wire, not so great for speakers.
Hard surrounds will utterly RUIN any speaker! Surrounds must be flexible!
RoyC has well documented at ClassicSpeakerPages that hardening the surround of a driver raises Fs. This is widely known, not disputed, and ABSOLUTELY TRUE, unlike nearly the entirety of what one reads about surround coatings on the interwebs of a thousand lies. The entirety of the issues were meticulously explained there, earlier in this thread, and in other detailed threads on AK.
These threads tend to run in circles, as earlier debunked material is endlessly recirculated because "helpful" late-comers to the party don't read the earlier postings and instead set forth internet dogma as if it were true.
FIVE YEARS AGO I set forth the details in this very thread on Page 3:
And on Page 4 I set forth the research quotes and linkage:
A simple search with Google can verify all of that information as 100% true and accurate.
I again refer everyone to the "Restoring the AR-3a" document over at ClassicSpeakerPages for plenty of information on sealants which is not based in mindless regurgitation of incorrect dogma. RoyC did all the heavy lifting on this, and deserves all the credit. He did the testing of various cements and caulks, proved that Fs was raised with any dopant other than butylene rubber, and that the original dopant is the one to use.
When Roy writes about speaker sealants it is an excellent idea to follow his advice and heed his cautions. To do otherwise will damage your speakers, likely irreparably so.