33 replies to this topic

[Maximo]

Slot Car World,

 

Since I am a current user and believer in the use of silicone-coated foam tires and also I am a Thingie Slot Car user/builder/collector, I would like any information and recollection of these Detroit products made by White Circle Raceways.

 

Any stories as well as photos of these white wonders are welcomed here!

 

If/are there any NOS White Circle silicone tires available, please let me know!

 

They were also referred as "Window Walkers"!

 

Maximo

 

[DocSlotCar]

Mid-America has some white or tan-colored 3/32" axle foams. Anyone help him silicone those foams for him?  

[bradblohm]

I've got White Circles specially done for Jerry Mrlik in green, orange, and silver!  No idea where they got that silicone back then!

 

I found, printed, and saved the patent years ago as I wanted to know how they made them.  Google is great, when you ask the right question!

 

https://patents.goog...atent/US3408770

 

Brad

[MattD]

The tires I recently got from Mike were Dow black silicone caulk.  There is a picture of the Dow in the thread.    If it cures thoroughly as a solid tire, it should easily cure as a foam tire coating.   dow probably makes this compound in white.

[don.siegel]

Fascinating stuff Brad, thanks! 

 

Didn't know about the first diluted coating, that penetrates into the sponge... but of course! 

 

Don 

[bradblohm]

Can't remember if it was in this patent or another source, but it spoke of heating the foam to open the cells for better silicone penetration, then after cooling it improved "mechanical" grip between foam and silicone.

 

Just GIVING away the secrets!

[don.siegel]

Here it just talks about diluting the silicone: 

 

The coating is applied to the base sponge tire by diluting one part of Silastic with one part of naptha or heptane and applying it to the sponge tire with a brush. The coating is allowed to be absorbed into the sponge for approximately five minutes. Following this, a full strength or undiluted coat of Silastic is applied by brush to the tire and allowed to set for two to three hours. When this coating has set, a final undiluted coat is applied and allowed to set.

(...)

This coating when cured forms a tough rubbery film which adheres tenaciously to the sponge due to the interlock established between the coating and the individual cavities or cells of the sponge. The small cell size improves the strength of the coating bond.

 

Don 

[jimht]

I had better results using Bestine (heptane) rather than naptha as a thinner for Permatex flowable silicone.

[MattD]

Jim, I had thought of using MEK to think the Permatex silicone.  Instead of just coating a foam tire actually  trying to get it thin enough so the tire would absorb it

 

What is "heptane"?

[bradblohm]

Bestine (heptane) is available everywhere, and I'm gonna get some!  Learn something new every day!

[MattD]

But what is it?   Is it a paint thinner of some type?    I will check my local ACE when I am there today.     Lot of experimenting ahead!

[bradblohm]

Short-chain hydro-carbon of some kind.  Used as a thinner.  Talked about being used to remove old glue.  Curious if it's in "moo be gone" or any of those kinds of products.  Anyway, I've got some "moo" on cases I want gone, so I'm going to try it, and, I'll have some for fooling around with silicone coating foam tires.  Of course that'll be TWO days after hell freezes over 'cause I'm booked solid until then!

[MattD]

Goo Be Gone will take that adhesive off a plastic box.    It is a citrus based product I think.   There is a similar product called Goof Off that works just as good.     when you open it and smell that orange aroma, don't take a drink of it.

[Bob Appelle]

Bob rented his first space from Jim Ursu at the Shores Raceway on Harper and nine mile road in Saint Clair Shores Mi, I use to help out coating tires. The process Bob used was a two pieces of aluminum  1x36x 1/8 bolted together and mounted axels with 64 pitch welden spur gears that rotated very slow. Put the tires to be coated on the axels. You would pour the diluted silicon in a tray about 6"x12" by 1/2" deep and hold it under the tires as they rotated until they were coated. Let them rotate until the were set up. I can't remember how many in a batch, but I would thing at least 200. It was a very simple design, but it worked great. I feel the white was the best traction over the clear or black. I worked for Jim and Loraine at Shores. 

[Bob Appelle]

Maximo, The window walker was a sales pitch, when someone wanted to purchase a pair, I would take them out of the package and put the tire against the vertical section of glass on the showcase and let it go. It would roll slowly all the way to the bottom of the glass. SOLD

[Maximo]

Thank you so much Bob! You answered in the spirit of my intent, that is to learn about the product and company.

 

Of course everyone's sharing of the process and technique to making these special type of slot car tires is welcomed as well. 

 

Knowledge is everything!

 

 

Maximo

[don.siegel]

Bob A - thanks much for giving us these historic details - that's a very funny image of 200 or so tires slowly rotating together... 

 

One question: do you remember where the original sponge tires and wheels came from? Was that a White Circle production, or did you buy them in from somewhere else? 

 

Don 

[Bob Appelle]

I use to B.S with the White Circle employee while he worked. He use to make the wheels  in the same shop as where they coated them. Just a lathe with a tool turret. He use to bang em out pretty fast. I don't remember the tire mounting and grinding process, but I think it was all done in house.

[Dale Tomczyk]

i remember the glass demonstration,pretty cool.i used to go to shores raceway in the summers(i lived in east detroit),didn't they have american tracks?used to go to jack and jill raceway too on 10 mile rd. as it was only blocks from where i lived.

[88honcho]

 

 

If/are there any NOS White Circle silicone tires available, please let me know!

 

 

Gator said,

Yes, but I only have one pair of NOS.

If still interested PM me your contact info and I'll forward it on.

 

[Maximo]

88Honcho,

 

Thanks for your generous offer, but no need to sacrifice your only set. I am okay with just the knowledge shared here.

 

Maximo

[Horsepower]

Now my question is where can I find a set of Black Moriah's with clear tires?

[olskoolslotz]

So what is a real White Circle brand tire? These were all obtained locally in the Detroit area.

[don.siegel]

Nice collection! 

 

First column, second down look like MPC's silicone-coated tires. 

 

I've got a new set coming to me soon, bought recently on ebay... 

 

Don 

[olskoolslotz]

Don,  those are .930 diameter and on 6-hole mag wheels so not MPC. They would be about the same size as the small diameter silicone coated tires that came on the MPC Offy. It's hard to get a sense of scale in my photo, I should have placed a 12" ruler in there.