hi

i need to stock up on o-rings for front tires. my local lowes just remodeled and got rid of their section with all the odd hardware items, like o-rings. checked an auto zone and had no luck. anyone have a good source for o-rings?

mike

Try your local plumbing supply store. I buy them in bulk packs of 100 for about $8.00. They have many different sizes to choose from. Just take an o-ring with you to compare what you need. Way cheaper than the big box stores!


NICK DANGER

Mike, like Ed said on the mailing list, McMaster-Carr (http://www.mcmaster.com/) is THE place for parts like this. From what I can tell, for AFX/XT car front wheels you should try size 107 and size 108 o-rings. They seem to be the closest size to a stock front tire. If you can, go to a hardware/plumbing supply store and pick up a pair of each of those and try them out before ordering in quantity from McMaster-Carr. Once you nail down the size you want they are quite cheap, depending on the material. The least expensive (Buna) are around $2.00 for 100 and other compounds (Viton, Silicone, PTFE, etc.) are more expensive. I've used Viton and it's very durable and stays flexible.

Despite the huge number of o-rings out there, very few sizes are appropriate for use on stock wheels. If anyone on the board has purchased o-rings that fit a specific application then go ahead and post the exact sizes here.

I got a couple of bags of O-rings from McMaster about a year ago.

One bag says "size 008", and the other bag has "size 010" printed on it. One bag is labeled "buna", and the other is "neoprene". Not sure what I was thinking at the time. Can't tell a difference in material by look or feel.

The small ones are for the Tjets, and the others are for Xtractions. Both are about as small as you'd ever want to go. The Tjet fronts end up at .325" or so, and the others are about .405" in diameter. Makes a HUGE difference in the handling of both cars.

Another option is buying one of those assortment boxes at Harbor Freight or one of the other junk tool outlets. Seems like it was $10. I have one of those as well, good for experimenting with the different sizes. Of course most won't work, but there are about 4 sizes that will.

i went to a local plumbing supply store, and they had very little. on the way there i passed a pretty well known local distributor of fasteners, Tacoma Screw. just for kicks i pulled into the parking lot to see if they had a retail store. they did, and boy did they have o-rings.

i got 5 sizes, 3/16, 7/32, 1/4, 5mm, and 6mm. the 3/16 are a bit small for xtractions, might work ok for tjets. so far i like the 1/4 and 5mm best. the 7/32 has worked fine for some chassis but not for others. if anyone is interested in experimenting with the different sizes, i will mail you 2 pairs of each size $2 including postage. if you find a size that you like, i will go back and get whatever quantity you need (within reason) at cost.

mike

Mike, what wheels are you putting each size on? Orings are spec'd out by their inside diameter, outside diameter, and width. Finding the oring with the right combination of all 3 spec's is the hard part. The size number, like 108, factors into all 3 measurements. So if you get a size 108 in any material you know its ID=7/32", OD = 13/32", and Width = 3/32".

Size 008: ID = 3/16", OD = 5/16", and W = 1/16"
Size 010: ID = 1/4", OD = 3/8", and W = 1/16"

I measured a stock AFX front tire and it was ID = 1/4", OD = 7/16", and width = 1/16". The stock OD of 7/16" is the same as 0.438". A size 008 is 0.313" and a size 010 is 0.375". The size 108 oring is 0.406". I'm not sure if lowering the front end on an AFX/MT/XT would help or hurt handling. I've tried the size 010 orings on a stock AFX wheel and I thought they were too small. I've never tried orings on a stock TJet wheel.

If Buna works good enough, that's great. They are the cheapest ones available, in the $2.00 - $3.00 for a bag of 100!

I got a couple of packages at Lowe's to try out (I forget what sizes)... they worked great for a while, but after a couple months they cracked and split. I didn't realize there were different grades. Apparently I have to go up the scale a grade or two... sounds like a trip to a real hardware store...

--rick

McMaster-Carr has a chart that lists the different grades.

Buna is definately at the low end and Kalrez 4079 is at the high end. A dash 010 Buna is $2.00/100 and dash 010 Kalrez 4079 is $21.68 each!

I've used the Viton orings and they seem to be indestructable and in a mid range price, $6.45/100 for standard grade or $11.46/100 for mil-spec grade for the same dash 010 size as mentioned above. I tried sanding some Viton orings to reduce the outside radius - good luck. Even on a dremel they are nearly impossible to sand.