Foam Tires for Dummies

swopemike · 12-06-2006, 10:37 AM

After the fantastic success of Ray Huang's "Rubber Tires for Dummies" thread, let's start "Foam Tires for Dummies".

OK, I'll toss out the first question...

Does anyone make foam premounts on nylon rims ?

I loved the new nylon rims for RP-30's. Very tough. Perfect for us "less than perfect" drivers.

coons88 · 12-06-2006, 04:48 PM

I think K Factory are on nylon rims.
What I want is a foam tire that won't chunk!

ShrekNZ · 12-06-2006, 11:42 PM

Quote:

Originally Posted by coons88

I think K Factory are on nylon rims.
What I want is a foam tire that won't chunk!

Come on Coons it's not that hard just avoid the curbs

I just hate it when you pick up a stone and cut the foam. By the way you can use gaffa tape for tyre protectors on 12ths or the inside of 10'th tyre protectors.

swopemike · 12-07-2006, 06:10 AM

What are K Factory, never heard of them? Where to get them ?

and what's "gaffa tape" ?

(ignorance abounds, thus this thread)

And so, foam tire experts, what is the best way to avoid chunking?
(I'm not counting driving better, let's assume accidents happen

).

I have heard CA glue the edges around the rims. I just keep forgetting to try this, too busy messing around on rctech !

coons88 · 12-07-2006, 04:11 PM

K Factory is part of Team Magic, do a search in Google, I'm sure you'll find it.
'Gaffa Tape' is also known as race tape if that helps? I can't think if anything else it's called. It is basically a black tape which is very strong, but it rips very easily (that may sound stupid, but it's hard to explain it any other way) It is used reguarly in real motorsports to quickly tape bumpers and other body parts that could be broken or hanging off the car.

bill941 · 12-07-2006, 07:10 PM

ca glue works well.Just put a little all the way around the rim then tap it on towel then let it dry and repeat.Do it on both front and rear on the outside edge.

bill941 · 12-07-2006, 07:11 PM

are you guys talking about duct tape by any chance?

loopedeloop · 12-08-2006, 04:28 AM

Quote:

Originally Posted by bill941

are you guys talking about duct tape by any chance?

yep

MikeXray · 12-08-2006, 06:18 AM

Quote:

Originally Posted by bill941

are you guys talking about duct tape by any chance?

although similar, they are different, the adhesive on gaffers/race tape doesn't leave the residue that most duct tape does, it also doesn't have the shiny finish, it's usually a matte finish.

When you guy tru foam tires do you round off the inside and outside edges, or does the inside edge stay square? I have been rounding it off lightly.

MManson · 12-08-2006, 07:09 AM

you round the edge, if you leave it square, its more prone to chunk,

Quante · 12-08-2006, 09:11 AM

Quote:

Originally Posted by bill941

ca glue works well.Just put a little all the way around the rim then tap it on towel then let it dry and repeat.Do it on both front and rear on the outside edge.

Well, what I found in 1/12th that if you use CA glue on the outside edge, when the CA glue breaks (and it will at one point) you make a small tear in the gummi and that grows larger to make a chunk ...

What I do is use normal contact adhesive (Bison kit), I think its calles shoo goo in the states.
This doesnt get hard but it makes the outside tougher but its still somewhat elastical (if thats the word :-) ) Do this once a day and it'll keep the tires good.
When applying the glue, try to open up every gap between the rim and the tire so the glue gets in between and there are no small bits of tire that get loose from the rim (cause this again will grow and make a tear).

Try it ;-)

timmay70 · 12-08-2006, 10:07 AM

A lot of times the cause of a tire chunk is the body getting driven into the tire and as the collision continues, the edge of the body gets driven off the side of the rim, taking a peice of the tire with it. A few tips to keep from shredding those nice foams; True your tires down, I ususally go to 57 - 59mm on sedan and 1.85 rear and 1.75 front for 1/12th. The gluing of the edges is minor compared to keeping the shell from ripping off peices. Another thing to do is round the edges of a fender crack, as these will also dig into the foam. The corners of your wheel openings, bend that corner (about 3mm x 3mm) to the outside of the shell. You are looking to keep the point from digging into the foam... To prevent the wheel arch from cracking, you can always back fill the foam bumper to match the molded bumper in your shell. The more support that it has, the less likely that it will 'pop' the fender. Good luck.

K_Spec_RC · 12-08-2006, 11:26 AM

when truing tires for a 1/12, what is a good starting place? also, wat is the minimum you would want to true? What is a good compound to start with as well? I know this would depend on the type of track and the grip available, but just as a general rule of thumb?

bill941 · 12-10-2006, 06:03 AM

i go 1.65 front ,1.70 rear but it's going to be different car to car depending what front your using if you have lowered arms and so forth.

AdrianM · 12-10-2006, 06:42 AM

All foam tires are mounted on high impact Nylon rims. The top US brands of foam tires for sedan are JACO, Parma, BSR and CRC.

Note that there are a series of foam compounds for nitro asphalt racing and a different series for carpet racing. Each type is optimized for the its type of racing.

Nitro tires have a higher rubber content and a different foam struture.

Carpet tires are sold by color dot ratings. (Pink, Double Pink, Cyan, Magenta, etc)

Nitro tires are sold by numerical shore (hardness) rating. (30S,35S, 37S,etc)

Carpet tires work on asphalt but wear fast.

Nitro tire don't work well on carpet under normal conditions. They need heat to get traction and if you use traction compounds they get gummy and too much traction.