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Re: Rubber

Posted: February 18th, 2010, 11:56 am
by smartkid222
[quote=jander14indoor] use slices off teflon tubes. I find the black plumbign O-rings to heavy and when the twist, they defeat the purpose!
Stiff enough to stay open when wound, but soft enough so the edges don't damage the rubber.
Low cost, I priced replacing the RC car antenna cover I bought 4 or 5 years ago (the remaining length is getting pretty short) with a new piece and its only 2 or 3 dollars. And I've cut a LOT of rings for the clinics I run from the piece I started with. You can also scrounge them from old ball point pens, spray bottles, etc. for nothing.
Wt, very low. A pair for SO is only .03 gm or so (you could probably go lighter but I don't want to risk the ring failing), less than 2 percent of the 1.5 gm SO max. Maybe I'm clumsy, but I lose more turns getting wound motors without O-rings off a winder and torque meter.

Jeff Anderson
Livonia, MI[/quote]

I dont understand how your O-rings weigh so little. What is the OD/ID?

Re: Rubber

Posted: February 18th, 2010, 2:41 pm
by jander14indoor
I'm not home, so this is from memory, but I think its like 3/32 id, by 1/64 or so wall thickness. I slice off pieces about 1/32 long, again from memory, my jig to do this safely and consistently is at home.

Oh, and I found the tubes again, they are not antenna covers, they are pushrod covers. Look in the RC supplies section of your hobby store.

Hope that helps,

Jeff Anderson
Livonia, MI

Re: Rubber

Posted: February 18th, 2010, 4:54 pm
by smartkid222
When you return home could you mass the tube and find how many g/in?

Teflon is a dense material to begin with (2.2 g/cm^3). I have some teflon but it has a large diamter and the O-rings are very heavy. I have another kind that is much thinner but i dont think it can hold.

**edit** nvm i figured out what i was thinking of.

Idk what pushrod covers are.
Thanks

Re: Rubber

Posted: February 19th, 2010, 3:26 pm
by Lowell
I just got my shipment of Tan Super Sport 3/32 rubber. Can someone tell me about how many inches will get me to 1.5? I don't have a scale yet and the one at the school does not measure tenths so anything above 1 would show up as 2. :/ Thanks!!

Doh! I just found the answer.

Re: Rubber

Posted: February 19th, 2010, 8:40 pm
by Greg Doe
Lowell,
I find 24 to 26 inches will yeild a 1.5 gram motor. I tie mine off, and if it's a little heavy,
tie it off again, and cut off the first knot. If it's still too heavy tie it off again! After doing this a few times you will have a good guess at how much weight you can lose each time you
trim. Don't lube your motor until after the last knot, unless you clean your rubber really well.
Greg Doe
Smyrna,TN

Re: Rubber

Posted: March 10th, 2010, 12:02 pm
by Taran
Doesn't Armor All freeze in the freezer? Or is it just my freezer?

Re: Rubber

Posted: March 10th, 2010, 12:48 pm
by andrewwski
It may, I'm not sure what it's freezing point is. Not sure why you'd want to freeze it though.

Re: Rubber

Posted: March 10th, 2010, 2:48 pm
by jcollier
Earlier in this thread, people talked about storing rubber in the freezer. I'm pretty sure they were talking about a specific batch of rubber that they wanted to use long term. In that case, get some out and then tie motors with it. I don't think there is a solid reason to freeze lubed motors after they have been lubed and wound. I could be wrong though.

Re: Rubber

Posted: March 10th, 2010, 3:15 pm
by smartkid222
I never really thought of that. I guess i meant both, lubed rubbers that i wasn't gonna use for a while (month+) and uncut rubber that i've accumulated. idk..

Re: Rubber

Posted: March 13th, 2010, 2:56 pm
by smartkid222
Tan super sport is considered the "best" rubber? Why is this so? what makes it superior to other types of rubber?

For the past few months i have been using Sig sport rubber because it was availabe at my local hobby shop. Today i got an order of the same size of TSS. I tried it out with the same number of winds and my [helicopter] didn't go nearly as high. It seemed it was more elastic and had less torque under the same number of winds. It basically acted like it was a thinner size rubber but it wasn't. I needed a lot more winds of TSS than the sig rubber to get to the same height. Now, if TSS breaks at a higher number of winds than it's ok, i could just put more winds on it. But if it doesn't wouldn't the Sig rubber be better.