13 replies to this topic

[James Grandi]

So! Here is a little bit of info for those who like to play with durometers - and spend money (unnecessarily in this case).

Left is a Shore 'A' scale durometer, bought it right off the parts truck at Stafford Motor Speedway in CT (1/2 mile oval).

Right is a shore 'O' scale durometer bought from an R/C shop.

Tested 4fourdifferent types of tire in three different spots (Thunder medium, HVR soft Wonder, JK small hub Wonder, Kelly Retro ). They all pretty much came out in the same manner, with a 1 to 2 point difference in reading at the most. Average them out, they're basically the same.

The lesson? Just because it's supposed to be better, doesn't mean it actually is LOL.

 

[gotboostedvr6]

What about shore 00?

[James Grandi]

If you wanna buy one, by all means, measure away and post your results.

[gotboostedvr6]

Material thickness will affect results dramatically.

[Garry S]

Shore Scales "A" and "O" use the same spring force, but a different point configuration.  
 
Shore durometer

[James Grandi]

Dennis Samson just explained the same thing to me on Facebook - I incorrectly assumed they used different calibrated springs.

As it turns out, it seems the modification I made to the Type A to make it useable for our tires inherently turned it into one that gives the same/similar readings as a Type O.

[Half Fast]

It seems to me that the actual numbers are meaningless, except for comparison purposes to determine the relative hardness of your sets of tires.
 
Cheers,

[Racer36]

I have an Intercomp Shore A and the Longacre R/C one as well. They read about four points different. I had hoped the rounded end would eliminate false readings with big hub tires, but nope.

[Cap Henry]

Durometer readings, in slot cars, are only useful for that user. With the way our tires are, it makes such a huge difference on how much pressure is applied, if you push it straight down or roll it into the tire. Great tool for comparing your own tires, but not very accurate from user to user.

I durometer all my tires for big races with move-ups so that if I move up and need to change tires I know what's the same as what I'm running or what's harder/softer if I need to adjust.

[Steve Deiters]

I see different  terms classifying durometers on Amazon -"Type A" and "Type D" or...

 

Any recommendations which is best suited for slot car tires?

 

Any brand preferences? Digital or dial? Brand?

 

Trying to make an informed choice on one of these.

[Racer36]

Steve,

 

Shore A seems to be the best and most common unit for slot or R/C tires.

[SpeedyNH]

I've used mine for years, mostly as a curiosity.  I sure am glad to see these differences explained, thanks! 

-and with mine, it's always been obvious to me that taking a good reading was mostly dependent on having a sufficient thickness of the rubber.

speedy

[Zippity]

Surely that regardless of which class of Durometer you possess, the critical thing is getting a constant reading between hard and soft?

 

Who cares what the numbers read.

 

Just as long as I can obtain a range of measurements, my Durometer is doing its job

 

Yes?

[Racer36]

Absolutely Zip.

 Anyone with an eye and an anus can figure out that there will be variances between durometers just based on production tolerances.

The idea is to get a feel for what works on track and use the durometer to fine tune from there.

Easy Peasey!

I used it in 1:1 racing, kart racing and now slots, all with good success.