Vanishing Rubber Cement (Patch Kit)

captain387

100 W
Joined
Jul 21, 2011
Messages
197
Location
Kingston, Ontario
Hello All,

Wanted to give everyone a heads up (Well at least those who have never came across this...)

You know the trusty inner tube repair kit you have for an emergency flat with the little tube of rubber cement,,,,

Well if you have broken the seal on the rubber cement to patch a tube and it has been sitting for some time,,,, not sure how long, 3 years since my last flat? The once 80% full tube will be completely empty, as in just air.

I found 3 tubes around the house, all empty.
 
That can happen even if you do not open the tube--the folded end is not completely sealed, so the highly volatile solvents can escape over time thru that.
 
Yeah. I'm a "belt and suspenders" kinda guy. So I always have two tubes of glue and a spare tube. One tube of glue that has never been used and the last one I've used that has been opened.

But Amberwolf makes a good point. I've opened old tubes (10 years or more I think) and they were dried out. We may need a new invention. Clear flexible blister packs of rubber cement. They would be flexible so that you can examine them without opening them to confirm the glue is still good. Also, since the sealed bubble could be made so that vapors either don't leak out or do so much slower. I guess you'd need to get the right plastic.

Off to file my patent ...

:^)
 
I'm not sure of any cheap plastics that are made thin (for tiny containers) that will keep the volatiles used in the solvents inside. Even the ones that don't actually dissolve the plastic itself will apparently still pass (slowly) thru the plastic's structure, based on what little experience I have with trying to store stuff out of damaged containers into other things....

AFAIK that's why metal containers are used for this stuff.

According to the Park MSDS it contains
Solvent naphtha (petroleum), light aliphatic
n-Heptane
Octane
1-Heptene

and the Rema MSDS shows
trichloroethelyne

dunno all of their properties but they're all pretty volatile, evaporating very quickly, and probably also penetrative of various materials (though I don't know for sure which ones, there's probably a data page out there somewhere with test results of lots of things).
 
We need peel-and-stick tire patches that actually work without glue. I haven't been impressed with the ones I've tried.

For sure I've had the same experience with the little metal tubes that come with a patch kit. Once you puncture the seal, it dries out pretty fast. I consider them single use items.
 
The best ones I've used were Park and Rema; the Park ones last at least several months (just had to use one today that I'd opened I think endish of last year).

The stuff in random noname patch kits rarely is still any good even a few weeks later, if that.
 
They have those tiny single-use tubes of super glue at the dollar store 4/$1. Seems like it shouldn't be difficult to do the same thing with patch cement.
 
Thanks for all the great info, need to keep eye on this stuff I guess

Well for me it was perfect timing to run out of rubber cement.
My parents were at my house and I noticed their back tire was half deflated, we checked on it an hour later after pumping it up and it had lost all the air again.

We rolled the vehicle and I spotted a screw in the tire, pulled out the trusty tire repair kit (rubber rope, and the two tools 1 round file and rope installer) Pulled the screw pushed the file into the hole to make it bigger. Tried installing the rope and was not cooperating, oh yeah the rubber cements helps it slide in...…..So there we were with the file in the tire to hold the air in looking for rubber cement.

We had lots of options with a hardware store around the corner, spare tires, spare winter tires.

Now if I was on the 60 lb bike 20 km away from home with a flat tire, that would be a different story.
 
So I was poking around for better solutions on the web and ran across the recommendation to use a fingernail polish bottle. Seemed like worth trying. It's kinda like a small rubber cement bottle. It can't out-gas through the glass and there are no crimped metal seams to leak either. The only source for a leak is the top, and that's designed to seal in acetone. So maybe it would do as well with Heptane?

So I went down to the dollar store and got a cheap bottle of clear nail polish (chose the flattest shape), dumped the contents, and rinsed it twice with acetone. After it was fully dried, I filled it with rubber cement. I considered using one of the brown bottles I had that used to contain tea tree oil, but thought they were too large. Also, nail polish bottles seemed tougher with thick glass for a small bottle.

You can easily tell by tipping the bottle whether the rubber cement is still fluid or not. I suppose that if it dried out you'd probably see a volume change as well. The brush that comes with the bottle is a bonus. I used BestTest rubber cement. If you don't trust standard Heptane based rubber cement because its solvents aren't quite as exotic as some of the patch cements, then just squeeze a tube of whatever cement you have into the nail polish bottle. But my test patch with standard rubber cement seems fully fuse to the inner tube using a simple Heptane based cement.



IMG_20190705_164602084_cr_sm.jpg
IMG_20190705_164615084_HDR_cr_sm.jpg
 
Nail polish bottle is a good idea, I didn't think of that. :oops:

Heptane is one of the solvents in the Park stuff.

BTW, the moped tubes I now use are supposedly mostly natural rubber, and some butyl. The Park cement works on those (just found out the hard way today).
 
I like the nail polish bottle idea. You can visually check it anytime.

Is rubber cement the same as tire patch glue?
 
I save up "holey" tubes, then purchase a kit and patch them all at once. That way I'm assured of at least three or four without worrying about the glue drying.
 
fechter said:
I like the nail polish bottle idea. You can visually check it anytime.

Is rubber cement the same as tire patch glue?

I'm going to run a test this weekend to confirm, but this is what I think I know.

1) Most common rubber cements are comprised of heptane and rubber solids. That's it. They used to have other solvents, but we've become overall more safety conscious and heptane is less toxic than other VOCs (volatile organic compounds).
I know some of this because VOCs have been a big deal in the Table Tennis world since players started using TipTop glue to adhere their rubbers because they found that it gave performance enhancing characteristics to the rubber. This ushered in the Speed Glue era in table tennis. Now VOCs are essentially banished and carefully tested for at the highest playing levels.

2) Slime "rubber cement" contains four solvents per the SDS. Major one is naphtha followed by heptane and hept-1-ene with a small bit of octane.
https://www.slime.com/us/sds-sheets.php
https://storage.googleapis.com/slime-com/uploads/Rubber%20Cement.pdf

3) Patches apparently work by creating a lot of cross-links between the inner tube and the patch. The two aren't "glued" so much as they are made to chemically bond to each other. The critical part of the process occurs when you rough up the tube. This isn't to just provide a rough surface to glue to. It gets rid of the most heavily cross linked outer rubber and exposes inner rubber that has fewer cross-links. When you apply the "glue", it begins to establish cross-links to this exposed rubber with the rubber in the glue. When you peel the foil off of a patch, it exposes a rubber compound that is primed for cross linking and it begins cross linking with the mostly dried rubber cement. Ultimately the three different layers are supposed to be heavily cross linked. So if all goes well, the patch rubber should become fused to the tube rubber.

I got the above from a post on reddit from someone claiming to be a chemist who seemed to really know what he was talking about. Yet he concluded that ordinary rubber cement won't work while my and other people's experience is that it works quite well. So maybe it works but not as well?

So I did a patch yesterday using standard Best Test rubber cement. It seemed to be tenaciously fused when tried to peel it off this AM. But I'm going to test further. Later today I'll apply some patches using regular rubber cement and Slime rubber cement. I'll then do some destructive testing tomorrow after they've have had a chance to cure overnight so see if there seems to be any difference in the bonds. Maybe I'll also to a short-term test after 15 minutes as well. It could be that the other solvents offer a speed advantage.
 
Good test; I've needed to patch tubes on the trail (multiple punctures); the glue supplied with kits will "fuse" the patch in 15 minutes or less, but it could be there is pressure from the tire affixing the patch as the tube is inflated.
 
MadRhino said:
Tubeless plugs are so much faster. I hope my patch kit dries as artefact. :D

Don't you use glue with tubeless plugs too? I wish the whole bike industry would migrate to tubeless but I guess there is a reason it hasn't.
 
fechter said:
MadRhino said:
Tubeless plugs are so much faster. I hope my patch kit dries as artefact. :D

Don't you use glue with tubeless plugs too? I wish the whole bike industry would migrate to tubeless but I guess there is a reason it hasn't.

I haven't done plugs with tubeless bike tires, but I have with cars. Both types I used involved using glue and required roughing up the rubber before applying glue.

Checked some YouTube videos and it seems like they rely to some extent on the sealant already in the tire. The video I watched also said that plugs are only a semi-permanent fix.
[youtube]9hj0gz-UC6o[/youtube]
The possible benefit I see for tubeless on a bicycle is that you can patch without removing the tire from the bike. That could be an advantage with my rear hub that is a bit of trouble to remove. I may not understand the situation well, but it seems like you are trading effort up front for effort in the case of a flat. I need to read more about real world situations. So tubes for me for now since I understand them fairly well.
 
I use plain rubber cement, the one from the shoe smith. I set the plug and glue on fire and choke with my wet thumb or the edge of the lighter. Yet I usually do that at home. In the trail I don’t bother, just twist a plug and ride.

There is a cush core insert in the tire, and some 5 oz of green slime. Since most of my tires are replaced before they have a single flat anyway, I can’t say I’m saving time, because of the time spent mounting the tubeless tire properly in the first place. BUT, when I do have a flat, it is not frustrating anymore.
 
wturber said:
The possible benefit I see for tubeless on a bicycle is that you can patch without removing the tire from the bike. That could be an advantage with my rear hub that is a bit of trouble to remove.

You don't have to remove teh wheel, or even the tire, to patch a tube, with the possible exception of something near the valve stem itself depending on your tire/rim/tube.

Yesterday (or was it the day before? cant' remember), on SB Cruiser, I had a flat at work (was a slow leak due to mesquite thorn, but I'd stupidly decided to pull out the many thorns I could see in the tire before leaving work, without thinking that the leak was probably caused by one, and still being mostly plugged by it).

Anyway, the repair was actually easy--I tipped (rather, had someone tip) the trike against a wall, to lift the wheel off the ground so I could spin it easily, and then pulled the tire bead off the rim, and pulled the tube out of teh tire at the point of the leak (thorn hole).

Patched it, put it back, reinflated it, and pulled the trike back down level, and went home. Probably took half an hour, and most of that was me waiting for someone to help me tip the trike, and cleaning my dirty hands/etc up afterward. The actual repair probably took 10 minutes.


If I had had to take the wheel *off* the trike, it would've probably taken an hour or more just for the repair, and I would have had to have someone tip the trike completely on it's side so I would be able to maneuver the heavy hubmotor wheel out of and into the dropouts, etc., taking even more time.


I used to do the samet hing on regular bikes by flipping the bike upside down onto it's saddle and bars.


Bicycle tires are relatively flexible, so it's usually pretty easy to get to any part of the tube's outer circumference, where msot holes are to need patching.


Thicker tires like the Shinko MC/Moped tires on the back of SB Cruiser are another story, and harder to get that access, but it can stil be done on a bike--on a trike it can be harder depending on how you can access teh wheel and tire--on SBC it's all from underneath and a little bit to the outboard side, nothing from the top or inboard,
 
amberwolf said:
You don't have to remove teh wheel, or even the tire, to patch a tube, with the possible exception of something near the valve stem itself depending on your tire/rim/tube.

Given that I have a tire casing, Slime strip, extra thick tube and that there can be issues with just identifying where the leak is (my most recent was the valve stem base), my general inclination is to simply dog forward and replace the tube. That way I can fully check for anything left in the tire that my continue to create problems.

I did finish my patch test comparing rubber cement to the "rubber cement" that comes with the Slime brand tube patch kit. I wasn't able to start last night, so my patch destruction test was done after the patches had cured for about two and a half hours, not overnight. The result summary is that rubber cement works fine but the cement that comes with the kit works has a marginally better and somewhat more tenacious bond. I wouldn't hesitate to use regular rubber cement, but if I had both available at the same time, I'd probably choose the "for the purpose" cement simply because it appears to be slightly better.

Here's a video of what I did.

[youtube]DNe2tksvJHE[/youtube]
 
Great test!

Regular rubber cement looks like it works pretty good. Another similar glue is Weldwood contact cement, which I can find in most hardware stores. No idea if that would work better but it contains:

Weldwood MSDS.JPG

Tubeless tires should have significantly lower rolling resistance and weigh less.
 
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