[DaveLat]

From time to time I read people refer to sponge tires and have often wondered what they were all about.I have never laid eyes on any! Could anyone enlighten me?
Pro`s and Con`s?
How good are they compared to rubber or urethanes?
Where can you get them from?
do they fit all cars?
any link to websites that have info on them?
etc etc

cheers, Dave

 

[300SLR]

Hi Dave
What sort of cars are you running?
Chances are that if you have never seen sponge tyres, you are not running the sort of cars that suit sponge tyres.

Sponge tyres produce way more grip than rubber or urethanes.
On a car that can make good use of that grip that's an advantage. Usually they run on metal chassis cars raced on routed tracks. High performance slot cars just about always use sponge tyres.
On a home set style a plastic chassis car, most likely the extra grip of sponge tyre is a disadvantage - they'll just tip out in corners.

Sponge tyres can be in bought either as blanks or ready glued onto hubs and trued to the most popular sizes. The blanks can be glued onto just about any hubs and true them up to whatever size you want. So yes they will fit just about any car, but its not necessarily a good idea on some sorts of car.

All the stockists of high performance slot car parts sell sponge tyres - for example
SCD http://www.chaskeelingscd.co.uk/
Won o Won http://www.won-o-won.com/
B Slotcar http://www.bslotcar.com/
AB Slotsport. http://www.abslotsport.biz/

 

[DaveLat]

Thankyou 300slr for the info, as I run more or less standard scaley cars on a home plastic track
then sponge isn't for me. I appreciate the info and can concentrate on urethanes
Thanks again, Dave

 

[RichD]

I raced at commercial 1/24th raceways for years and sponge tires are used exclusivly on those. The tires come glued and trued on metal rims. Without using some sort of tire conditioner spongies are nearly useless, which is one reason that they are seldom seen on home tracks. A few years ago we were hosting a proxy race and one of the cars had sponge tires. As I had expected the car had very poor grip. Just for kicks I treated the tires with suntan lotion, which was a great improvement. The suntan lotion did not last as long as traction compound would have, but it does not make a mess out of the track like traction compound does when it is used in excess.

 

[thestig514]

Hi,

At our club, we only run sponge tyres. We even use them on our Spirit Peugeots; we use Parma Tuna tyres cut down to size. They are grippy normally, but can provide even more grip with a tyre solution like Parma Tire Traction. However, they provide so much grip that weight needs to be added to the front of the car to stop it understeering, and they do wear at a rate of about 0.25 mm per 15 min club race.

Cheers,
thestig514

 

[RikoRocket]

QUOTE (RichD @ 10 Jul 2011, 14:44) <{POST_SNAPBACK}>I raced at commercial 1/24th raceways for years and sponge tires are used exclusivly on those. The tires come glued and trued on metal rims. Without using some sort of tire conditioner spongies are nearly useless, which is one reason that they are seldom seen on home tracks. A few years ago we were hosting a proxy race and one of the cars had sponge tires. As I had expected the car had very poor grip. Just for kicks I treated the tires with suntan lotion, which was a great improvement. The suntan lotion did not last as long as traction compound would have, but it does not make a mess out of the track like traction compound does when it is used in excess.

I bought lots of Parma metal chassis sponge tyre cars in the 80's with a view to running them on classic scalextric track. They were next to useless. Then after I joined Larkfield Raceway a few years ago I discovered that you could actually buy the goop that the tyres need to perform. They were brilliant! Just up to the point that the sliding rear ends deposited enough goop on the rails to stop the cars from working. They are designed for routed wooden tracks and that is where they should stay IMHO

 

[Camber]

We use WD40 on sponge tyres, works very well.

 

[rick1776]

Sponge tyres are urethane tyres!! An additive is placed in the urethane mix during two part mixing which causes the release of oxygen. This is trapped in the urethane as it sets, hence the "sponge" trye effect.

cheers
rick1776

 

[RichD]

Actually the blowing agent is a hydrazine derivative and it releases nitrogen. If the cells were filled with oxygen the tires would probably be hard as a rock before they were sold. WD-40 works because it contains oil, 11% if I recall correctly. Suntan lotion also contains oil. Traction compound does not gunk up the rails as much as the rubber dust that gets stuck in it. Lighter fluid (naphtha) is good for removing the mixture of rubber dust and traction compound, but you only should wipe down the rails.

 

[dgersh]

Very interesting that, thanks guys... how does that apply to the original "German" sponge tires (actually model airplane tires with the skin taken off) and the later "closed-cell spongies" that most of us know?

The drawback to the sponge tires is of course that they do dry out relatively rapidly, so have to be replaced, besides the fact that they wear out a lot faster.

However, there's also a much denser type of sponge, like that used on the White Point cars, that seems to work on wood tracks without requiring anything except cleaning, and also doesn't seem to dry out as quickly (I still occasionally run on the same pair I originally mounted about 10 years ago!). Not sure how these do on plastic track tho...

Don