Double Flange wheels

[Perrotoro]

I have two NSR cars in my fleet - a corvette and a Mosler. I can't remember if the Mosler came with a double flange wheel, but the corvette did. I tried several tires on the double flange without much success.

Please enlighten me - what is the intent of the double flange? Is it to provide a concave contour of the tire slick's contact surface?

Does it have a place in a Carrera-home-digital-with-magnet application? I'm ready to give it another try if there's merit to it.

[RichD]

NSR uses what they call "air" wheels and those are different from regular double flange wheels since the flanges are are closer together. Most 1/32nd wheels have a solid center ridge, with NSR wheels the middle of the ridge is removed and that space is only filled with air when the tire is mounted. With ordinary double flange wheels the flanges are located at the very edge.

If you measure the width across the flanges of a NSR wheel as well as the height of the flanges you can compare that to a wheel with a solid center rib and probably find silicone or urethane tires to fit. I have one NSR car with air wheels and I have silicone tires on those.
You are going to be better off if a mounted tire has a perfectly flat tread.

[Perrotoro]

Thanks. I have mostly flat contours on solid hip wheels - though I probably need to true a couple that I have not yet done.

So with the Flanged wheels, either NSR spaced or full width, what is the objective? It would seem a flat contour is not easily achievable with flanges - regardless of the spacing. Is it a track-type characteristic or tire-type for which flanges provide benefit - or what?

Thanks

[RichD]

The objective in both cases is to keep the tires from sliding off the wheels! With wheels that have flanges at the edge you have to use tires that are the right width. If the tire is too wide it will sit on top of the flanges or possibly only on one flange and the tire will be distorted so the tread will not be flat. If the tire is too narrow at least the tread will sit flat, but it will tend to slide back and fourth between the flanges. If you are using tires that are plain donuts the flanges will always be sticking out, that is never the case with 1:1 wheels. If you wanted the wheels and tires to look correct with flanged wheels you would have to use tires with indentations to match the flanges. I believe that is one reason why center rib wheels are more common. Another advantage to center rib wheels is that the tires can be too wide or narrow and still work well. The big hitch with center rib wheels is that the height and width of the rib is not standardized at least in the case of the plastic wheels on RTR cars.

[dw5555]

I never understood the concept of the Air wheels. I would spend time truing the tires only to find that after running on the track for awhile the contact patch was on the outside of the tires. Some people I knew used pieces of foam to fill in the area between the ribs creating more of a contact patch. Personally I don't like them but if you're gonna run mag I don't think it will make that much difference.
Dave

[mikeinclover]

We have run the NSR national's the last 3 years. The first year everyone was pulling them off and exchanging the for a non air ride wheel. The second year a few guys tried them and did well. This year most of the Modern GT class ran them. I allowed the use of the Thunderslot foam insert it people want to use them and some did. As for the vintage some range the air ride but most just exchange the front and rear wheels since they are the same size and the front wheels are standard.
Quick Slicks does make a tire that will fill that gap for the most part. It is for the Thundslot cars TS43, TS44. They would probably be a little big for a GT car though.
Mike

[Perrotoro]

So what is the concept? Does the Silicon, rubber or Urethane, stretched across two flanges, if properly set, yield a soft high performance configuration of rubber sitting on air? ...vs. sitting on a hard center-rib? Is that the simple basics or is there more?

I don't think it sounds like something that I need to worry with for low-end home fun racing among friends and family that will likely never appear in a slot car shop or club, but I'm still want to try to understand the concept.

[Perrotoro]

Or maybe I can see how the flanges might lend itself to help assure a flat tread - if properly set?

[chrisguyw]

When the "air ride" wheels first were introduced it quickly became common (mostly in Europe) to........1/ Glue both beads of the tire to the wheel...2/True and treat the tire,.....and 3/ Use a syringe to lightly inflate the center portion of the tire. This supported the center section of the tire, creating a flat contact patch, but much more importantly, tended to "soften" the tire, allowing it to compress more readily and progressively (more akin to a sponge tire). This let the outside rear tire compress and load more effectively, improving grip, and, lessened chatter. (There are many other critical elements in the causes of chatter, but, tires are certainly a factor ).

(I should also add that any of the processes outlined here apply mainly to treated rubber tires used on a wood track.)

The issue with this process was that the tires only held air for a heat or two, so racers were running around with syringes between heats, and syringes were to be seen on most slot boxes/counter tops................this was not the optic most shop owners were looking to project, and this practice was largely banned 4/5 years ago.

Alternatives were sought, and the practice of using old bits of 1/24 and 1/32 sponge tires to fill the gap between the flanges became more popular....(several on this forum are solid proponents of this, and have been for some time). It has clearly been common enough, that now a few of the plastic car manufacturers are offering sponge fillers for this specific purpose.

My personal observation is that the sponge is not as effective as the "inflated" tire, but, I do consider it worthwhile, I have been using it for a couple of years, and will continue to do so. (Sponge does have one advantage over the "inflated" tire process.......it lasts,.....so no issues with multi event proxies).

I have tried this process with several Silicone, Urethane, and untreated rubber tires, and while I have not been disappointed, I have not found the results to be of the magnitude found when using treated rubber tires.........neither Silicone, Urethane, or untreated rubber will compress as readily as a treated rubber tire, so the effects are negated.

Cheers
Chris Walker

[Perrotoro]

Awesome explanation! Thanks for taking the time - I'd have never guessed. And still laughing at the mental vision of syringes in shops and squirming in my office chair about being around syringes. Center rib for my home stuff for sure then!

[chrisguyw]