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I wasn't sure where to post this question as it isn't necessarily scale specific, etc.
Recently I purchased some tires that were cast with 60 shore urethane (designed for use with static models)
Never having handled anything cast in 60 shore, I wasn't sure how much stiffer that would be than 40 shore and thought that I would give them a whirl.
:D
The sidewall and tread detail on them looks great, however, as no surprise, they are notably stiffer and I think they are going to be a wee bit too hard to use on the rear, after mounting and truing in their current hardness state.(although the current outer skin has some good "tack" to it)

I wasn't aware of any method of "softening" cured urethane - but thought I would throw it out to the group and ask?
Soooo... that being said, any options besides making a mold of these and learning to cast my own tires?
:think:

I'm sure there's better, but I use a swab to put a coating of Mineral Oil on my Paul Gage tires before I race. Cleans, softens (but not too much), and isn't as harsh as some of the other products (i.e., Monster) I've tried. YMMV.

I use 60 shore when making front tyres - I can't think of anyway of softening them that won't ultimately lead to the urethane breaking down.

I don't let anyone use tire preparation on my track. There is a good layer of rubber.

My experience is that urethane tires doesn't really take to any of the various softening oils. If you true the tires, they might actually grip good enough.

Brian

I use 60 Shore urethane tires on the front of several of my 1/32nd cars, I even had some special ones made for HO cars. I cave given samples of the HO tires to a number of people, but there was not enough interest in those tires for them to be commercialized. Last year a fellow racer dropped by my place for a test session. He put a car on the track and it had almost no grip, it seems that he had used those hard tires on the rear wheels.

Thank you for the feedback gents...
I may try mounting and truing a set just to try - but from the sounds of things, if I want any kind of permanent change it looks as though I may be learning to cast tires in short order.
(if I want to use these designs for drive tires)

I did receive one suggestion from a local that I plan to try - as I have nothing to loose in if it doesn't work - and that is to place them in water, bring to a boil and then let slow cool off the stove. Not sure if will have any appreciable or lasting effects - but can't hurt to try. :)

Soooo... I guess the next question is - any recommendation on good black urethane to use?
:)

In the past I have used Smoothon reoflex but have some vytaflex to try.
You will need to purchase a pigment separately so look to the supplier of the urethane for that.

Rubber is measured by a shore number and if it is advertised at a certain shore rating, I can't imagine that boiling and cooling would change that rating. Since you have nothing to lose, try it and let us know what happens. If you want to start making tires, go for it. It is time consuming and does cost a few bucks to get started. If you have 100 cars that need tires, I would certainly make them myself. If you have 10-20, it might be easiest to order a few at a time from one of the guys that make them. Faster with no learning curve!

Paul Gage is the favorite here, but there is also a guy in France that sells on Ebay or direct and his tires are superb from 2 part molds that have finished detail front and back.

just my 2 cents

I kind of figure this boiling thing is a long shot - but like I said, I have nothing to loose with it - so I'll give it a shot.
:think:
On casting - I very much enjoy my Paul Gauge tires, and haveI also have had good luck with tires from France (that is my source pie crust 1/32 slicks!)

The tires I am working on now are for 1/24 drag and jalopy type applications, which unfortunately have limited options available from Paul Gage.
I have picked up "Shot Gunz" tires from SCC and hope to be getting a couple sets from BTaylor down the line - but naturally, there are still some "holes" I am looking to fill to get the "look" I want for a couple builds I have in mind.

Having done resin casting of the HO and 1/32 bodies, I am assuming (hoping) there won't be a big learning curve with casting tires. I just need to educate myself about what is available / preferred on the urethane front to minimize ending up with urethane that won't work for this type of application. :)

Looks like some fun on the horizon!
:auto-layrubber:

Urethane tires made for rear wheels are probably 25 or 35 Shore. I do have a durometer and I have taken readings, but you really need a slab of material to get good numbers. The best poured tires are made using CNC machined molds. A number of people have done pops of existing tires using flexible molds, but tires made in those are not going to be perfectly round. If you do cast tires that way you might want to make the OD a bit larger. That way the tires can be glued on the wheels and trued without ending up with an undersized diameter.