thorsteno

Hi All,
I have an older 8 ounce can of Rem Tip Top cold vulcanizing fluid that isn't very "fluid" anymore.
Has anyone tried thinning with mineral spirits or other solvent?
Email to Rema USA has not been answered.
Thanks in advance for the help/comments.
Sincerely,
Thorsten

Deetox

Acetone will work or you can buy this stuff:
https://www.amazon.com/Bestine-Solve...dp/B004O7HM38/

Also a good idea to store the can upside down to prevent air from getting in.

cyccommute 

Acetone might work but it would be best to test it in small amounts first to see if there is a problem rather than waste the whole batch.

Air doesn’t cause any problems with the vulcanizing fluid. It doesn’t cause the fluid to oxidize and just having air in the can won’t cause the solvent to evaporate. Keep the lid closed, of course but it shouldn’t need to be stored upside down.

pdlamb

Rema has used at least two solvents, so check the can. For my first can that got gooey, I was able to source some trichlor which thinned it out for a couple years. The replacement, when the first can went bad eventually, used something else (hexane, maybe?), and touching that with trichlor seemed to polymerize the whole can in no time flat.

I suspect that you're seeing sulfur cross-linking in the dissolved vulcanizing agent, and you're not going to get much more out of that can. Given the high cost of the solvent, you're probably better off tossing it and buying a new can to patch future flats.

FWIW, the "new" can of Rema I bought off Amazon a while back barely lasted two years -- I suspect it was old when I bought it. I was able to find some Slime at an auto parts that has lasted ~5 years so far.

thorsteno

Thanks for the suggestions. Bestine sounds very effective. Carcinogenic no doubt. Storing upside down might be a hassle since there's a brush attached to the inside of the cap. Maybe I need to join the tubeless revolution someday.

ThermionicScott 

If I were in that position, I'd keep the can sealed until I had a BIG batch of tubes to patch up. Minimize the time it's open.

2_i 

Rema used at least 3 different solvents over time, heptane, trichloroethylene and naphta. I used the first two successfully to dilute their vulcanizing and likely also mineral spirits. With solvent added once in a blue moon, the can of the fluid last forever, unless in a bike shop, I suppose.

cyccommute 

They seem to be using heptane and acetone now according to the SDS. Trichloroethylene (TCE) seems to have been used in older formulations. Changing to heptane and acetone may have necessitated some formulation changes.

It’s not likely to be polymerization in the can. The fluid in the can is mostly unreactive and the sulfur source isn’t in the can. The promoter that contains sulfur is on the patch itself. The can will lose solvent quickly when open since acetone and heptane (and TCE before that ) have high vapor pressures which means they evaporate quickly.

Solvents aren’t that expensive. A lifetime supply of acetone…i.e. 32 oz or about 2L… is about $9 at Home Depot. Mineral spirits could also substitute for the heptane (test on a small amount of fluid first). I doubt you’d need more than a few mL of either. 15 mL (about a tablespoon) would be enough.

I’m not sure it goes old as fast as all that. I have unsealed tubes that are more than 5 years old as well as being stored in a unheated garage. They are still good.

Additionally, using rubber cement like Slime doesn’t do the same thing as using vulcanizing fluid from Rema. The patches will stick to the rubber cement but they don’t do the chemistry. There are other chemicals in the fluid that work with the promoter to form new sulfur bonds. Those chemicals aren’t in the Slime cement. Even if you have another vulcanizing cement, you may not be getting the same reactions because there are several methods of doing cold vulcanization. Rema is a two part system of the patch and vulcanizing fluid. Take one of those parts away and it doesn’t work the same.

cyccommute 

Bestine is relatively safe. It’s almost completely heptane which, along with acetone, is what is listed in the Rema SDS for cans of vulcanizing fluid. Because it is a saturated hydrocarbon, it is basically unreactive. It is flammable and I probably wouldn’t bathe in it but it’s relatively safe to use. Acetone, which is still safe, is more likely to cause irritation.

thorsteno

That's a good idea. However, I only flat about once a year! Touching wood.

ThermionicScott 

Same here! It's a good problem to have.

bikebikebike

Is tire patch "cement" rubber cement or a de-vulcanizing substance?
I seem to recall someone saying there was a difference.
Relevant as the Bestine is for rubber cement.
Basic as it is , if there is a discussion of this common and basic chemistry, I have missed it.

I read through
https://www.sheldonbrown.com/brandt/patching.html and https://www.sheldonbrown.com/flats.html as welllas https://en.wikipedia.org/wiki/Rubber_cement
and it is a good refresher , they call it rubber solution and "a special rubber cement" not rubber cement.

They are both rubber cements, but formulated differently (different solvents, and probably different rubber too)
. The traditional Rema Vulcanizing Fluids (203 ,204 and 205) use trichloroethylene as the solvent in which a rubber is dissolved.

cyccommute 

Bestine’s SDS says that is is 100% heptane.

Not since August, 2019. The SDS of that date lists heptane and acetone as solvents.

Bestine would probably be sufficient as a diluent for Rema vulcanizing fluid.

bikebikebike

Thanks
One concern on a lot of internet "resources" is they are not attributed or date stamped.
Trolling through the available stuff, with my "Chemistry for the non science major" back ground of conversational biochemistry,
it appear that many solvents, hell even duct tape, can be used in patching, and I haven't yet found any comparisons for optimal vulcanizing patches
or even data on flat out failures
with the overwhelming preponderance being totally anecdotal. That at least is a data point.
Usually when there is one thing that works best,most other stuff fades away.
That being a round about way of saying there are a lot of workable near equivalences and there maybe best stuff, but nobody proves it.
not that that's a bad thing. lots of stuff works. good to know in a pinch.
It's what made Sheldon famous and why my wife only buys branded products.

Eric S.

I don't have to patch tubes enough to go through the tiny tubes of vulcanizing fluid very frequently. I've opened "new" tubes that I've had for a long time and found them dried out. I do have a large container of Slime fluid that I store upside down. I'm no scientist but it does make some sense as far as potential air transfer that could slowly dry it out.

bikebikebike

All container systems have porosity to some degree.
We are after all, made of atoms , that are made of waves.
I remember the story of the "paraffin creep" that killed Scott in Antarctica and cartridge CO2 losing pressure in tires.
That said, with 78 tires in my life, I still just get little tubes and use 1 a year.
They cost so little . I'll buy a handful off eBay every decade or so.
Prolly costs what a can does. I think the cans are for guys with tractors.