The Brown Dust on Proline/Losi Tires

[vantee2001]

As some of you may know that once in awhile you'll come across a thin film of fine brownish dust covering almost the entire surface of either a Proline or Losi tire, especially soft offroad ones (like the M3 and Silver compound). Well, the brown dust is NOT dirt from the factory and is a chemical compound known as CUMATE (manufactured by a huge chemical company called Vanderbilt).
CUMATE is a crosslinking agent for rubber, meaning it contains sulfur and is used to cure (or vulcanize) masterbatch raw (uncured) rubber turning it into whatever shape of the mold the rubber is in with the help of heat and time.
The reason for these excessive CUMATE to appear on the tires' surface is that much of the butyl rubber in the Proline/Losi blend is not curable and therefore not all the CUMATE is consumed during the curing process. However, if less CUMATE were to be used, then the uncured rubber will need much longer time to cure, meaning more time needed to manufacture the tires, thus reducing the tire makers' profits.
CUMATE is toxic, wash your hands after changing/mounting tires and before you handle the cheeseburger or pizza.
TRUST ME, THE CUMATE FILM ITSELF WILL DO NOTHING TO ENHANCE THE TIRES' PREFORMANCE!!!!

[jeepinator]

Motor spray ... OMG. Eliminating one vile chemical with one that is far worse.
Heh, that was not meant as a flame.
I suggest Simple Green. I swear by it. It will make your tires shiny, clean the dirt and grime REALLY well, and they will be STICKY when you are done. The "brown stuff" will be gone as well.

Dale, how toxic is this stuff ?
How do you know the stuff you have shared with us ? Do you work at that place you gave us the link for ?
I have always been interrested in how they come up with these tire compounds. I am also VERY interested in why they are so out-of-control expensive. $12 for a pair of buggy tires ? That is downright ridiculous. I am back in to RC pretty heavy now, but 2 years ago I finally gave up trying to afford tires. I find it IRONIC that the most consumable item on an RC car is also the most expensive.
I am not claiming conspiricy, or price gouging (OK, well maybe I am claimg price gouging), but I would sure like to have justification for the prices we have to pay for tires.
Example (assuming list prices, which most LHS's charge for parts and such):
XX4 buggy
front rims: $6
rear rims: $6
front tires: $11
rear tires: $12
total: $35 !

That is just stupid. To add fuel to the fire, the industry has somehow been able to advance everything we know about RC since 1984, yet we STILL GLUE TIRES. How convenient. We have batteries that have 2.5 times the capacity of the original 1200's. We have ultrapure synthetic shock fluids. We have viscous couplings (namely hydradrive, but there are others). We have ESC's that have space age ultra low on resistance and tons of other cool features. We have ultra advanced composites in our chassis and other components. Yet we still GLUE $12 tires on DISPOSABLE $6 rims ! $3 for 1 ounce of plastic ? Someone, please, help me calm me down ;)
Just think how far the hobby has progressed technologicaly since 1984 (I have chosen this year due to the release of the RC10, generally considered the first true race oriented kit).
Some of you race on tracks that are very nice on tires. Maybe you can get 20-30 runs even. Some tracks around here eat the crap out of tires. 10 runs would be BALD on some days (outdoor track).

OK, sorry for the rant, but do I have a point or what ?

[Obi112]

Absolutely you have a point! I'm just glad I bought a B3 as opposed to a T3 ($12 for tires versus $17). Does Associated make three-piece wheels any more? I'd like to pick up a set to put bashing tires on, while saving the one piece for racing...

[jeepinator]

BTW, my previous post in this thread was in no way an attack on Dale. I appreciate his sharing of this very interesting information.
He only got me to thinking about a few things, and I kinda got myself worked up. I still stand 100% behind the content of my message though.
My apologies to Dale ...

Cheers

[vantee2001]

Jeepinator

No need for any apologies. I know why you are annoyed by them prices, so am I.

Just remember, up to this point in time, there are no myths about making RC rubber tires. Not even the foam tires!

Have fun with you RC10, it's my favorite too..:-)

[XXXER]

Jeep, you forgot to complain about Foam Inserts, ream me for 3$ more will ya......

I usually just use simple green, or tire sauce to take it off, and i hate the smell of new tires, i always wash my hands before eating something because that smell knocks me out :eek:

[Roach Racing]

So what are you trying to tell us Dale? In case you don't know this is why people are burning there tires. To get rid of this compound. Your right it will not help with traction, but I think that's a given dust on your tires is not good for anything.

Just spray the tire with motor spray and wipe the stuff off, that's what I do.

[SirSpeedy]

Why arent' you guys re-using your wheels?

Get a gallon of acetone, put it in a cookie jar, put the tire in for 10-12 hours, and they come right off.

[jeepinator]

Really ?
Wow, I MUST try this. Is acitone basically nail polish remover ? 'Cause I have heard of doing that.
Your telling me that the super glue and the tire just, "come right off" ?
No work, no mess, no fuss ? :D

Hehehe, well I'll give it a shot. I tried boiling once, that was a complete failure :(

[Ultimaxx]

Well guys that a pretty good idea about the acetone but have you ever tried boiling your tires off? I did for my T-maxx tires and it worked! I boiled them for about an hour or so, then i puts some gloves on and worked the tire off. EASY AS PIE!!!

[Nairb]

Dang, I need to stop pulling tires onto the rims with my teeth. I'm serious! Some things are hard when your fingers really don't work, just FYI.

Jeepinator, you're the man! I absolutely agree! You should try $50 for a set of tires and wheels for a truck, though. We R/Cers pay a HUGE premium for so many things, it's not even funny. It torques me pretty bad, too. All your reasoning is exactly right. I honestly don't know what it will take to change the manufacturers' & resellers' minds & thinking, though. It's pretty sad.... :( Some people are getting pretty rich off of us, that's for sure.

[Nitro RS4 3]

Hey, want cheaper tires/wheels? Try touring. All products are Yokomo and prices approximated from previous purchases (Tower Hobbies and LHS):
4 rims: $6
4 medium slicks: $15
4 inserts: $7
Total: $29
Still not cheap, but inserts can be reused assuming you didnt destroy them. Then it would be only $22 for tires and rims. Spend a little more in the beggining for HPI rims ($12 for 4), and you can boil them and reuse them (the Yokomos will warp). Even more money saved in the long run. Then you can just spend $7.50 per pair on tires and go on your merry way. Mine have lasted over half a gallon of fuel and hopefully will hold out for another gallon or so.

[SirSpeedy]

Now THAT is some funny stuff...."Try touring"

I assume you are talking about Yok Sprints. That is a ONE run tire....maybe two if you have the right compound for the track temp. Almost all sedan tires only have one fast run. Then 2-3 fair runs.

A pair of X-2000's will yield 3-5 fast runs, depending on the surface. That is in mod as well.

Too funny.....worth the stop....

[SirSpeedy]

And I forgot about all the variables within one tire compound!

10's of differnt inserts, air gap between tire/insert, wheel stifnes, belted/non, bead shape, insert shape...........

[Nitro RS4 3]

Well, then explain how my tires lasted over half a gallon and are consistent and still going

[FilthyPierre]

Jeez, you guys have it good. You should try being into R/C in Australia. The prices here are outrageous. Rims and tyres are on a par, by my calculations about $76 to $80 Oz for a set of rims and tyres for a Losi XXX, which is about $38 to $40 US (roughly). A set of glued Proline foams on Proline rims for a TC3 is upwards of $90.
But other things, for example a Novak Cyclone is $410 Oz, ($205 US) and a XXX-T is $630 ($315US) RRP here. The internet makes it easy to get things a bit cheaper, but then you have to wait for shipping (up to 4 weeks in some cases), and if customs wants to, you can get charged import duty and GST. Tyres are difficult to import - unless the hobby store you buy from declares that they're new tyres (most times they forget), customs will quarantine your package for as long as they want to (up to 3 weeks), and you'll definitely get hit for import duty and GST.
Most times, I can cop the prices, it's just finding a hobby store that actually stocks what you want is the difficult part....
Off topic I know, but had to vent :)

Interesting about the brown dust - I had no idea that it was bad for you - I actually don't mind the smell of new rubber; I never bother to wash my hands after gluing a set.... geez, maybe that explains the rash, the twitching and the memory lo.... where was I ?
Seriously though, with all your laws over there, why isn't there some sort of warning - "Do not eat", "Wash your hands after handling rubber or going to the toilet" or something like that on the packet? A Novak Cyclone's packaging contains a warning about it containing a known carcinogen (the lead solder) and I'd hazard a guess that somebody would be more likely to ingest the brown tyre dust than munch away on a Cyclone....
"Food" for thought ;)

[ 05-22-2001: Message edited by: FilthyPierre ]

[rc51racerx]

NitroRS4 those are sprint tires you are running. I wouldn't race those on my car for more than a few runs.

EDIT: this is where I begin to address everyone not trying to attack you Nitro ;)

I run Yokomo G's, and they are 28 bucks for the tires alone. I go to the track race a few days, and I renew my debt with another 50 charge on my card to get new rims and tires for the ride. I thought I was getting "reamed" to use XXXER's words when I paid for my new ESC, but whoa in just a few months I have nearly bought two of them with the money I have dropped on tires. Acetone?? talk about a nasty chemical ;-) It probably works.. boiling tires works too, but you have to put a good bit of salt in the water to raise the boiling point. then boil them for an hour or more, and spoon em off. I agree though, in all the technological advancement the industry has seen you would think we wouldn't be glueing tires anymore.

--John

[ 05-23-2001: Message edited by: rc51racerx ]

[Kevin_366]

I just use hot glue for my tires..lol :p
works fine for me!

Kevin ;)