KR> Tire pressure and Slime/Nitrogen
Of course compressed air is 78% Nitrogen. You use nitrogen on struts because it's dry so you don't add moisture to the strut. Nitrogen in tires is mostly a waste of money for tires since some moisture and 20% other gasses included aren't going to make much of a difference in the leakage rate. -Jeff Scott ? Nitrogen is supposed to be better to not slow leak because the molecules are bigger than regular air. I always took that with a grain of salt thinking how much of a difference can it make. A few months ago I helped a neighbor rebuild the nose strut on his 172. He wanted to fill it with nitrogen instead of regular air, but our friends nitrogen bottle was empty. I have a CO2 bottle with a regulator for portable use of air tools and figured that would be as dry as the nitrogen and just as good. We filled the strut and the next day it was empty. Did it again and same results. Googled and found that CO2 has molecules smaller than regular air so we filled it with air and it has been good since. So, how much slower would nitrogen leak than air, no idea, but worth a try. Airline tires are filled with nitrogen for less leakage, more convenient on the line to roll out a nitrogen bottle than a compressor that can go to a few hundred PSI, and less expansion at high temperatures. Original Message Subject: KR> Tire pressure and Slime From: Mark Langford via KRnet I put all new tubes and tires on 1JF when I refurbed it, and it's had a slow leak ever since on one side. About a month ago I put some Slime in it, and it's still holding 50 psi. Something to consider. _
KR> On slime and nitrogen in tires.
A note for those using slime in their tires. It is fine on tires that use tubes, but if you really want to piss off your local tire dealer, use it on tubeless tires. It makes a real mess on the wheel and difficult to work on. The reasons for using nitrogen to fill tires is that it doesn't migrate through rubber as fast as air, it expands and contracts less than air does when the tire temperature changes, and it contains less water. http://www.popularmechanics.com/cars/how-to/a3894/4302788/
KR> Tire pressure and Slime
Bob and Dick Kohler present a method of mounting tires on split aircraft rims. Dick specifically shows how to avoid pinching the tube on the split rims. No need for slime. Use either site depending on your search engine. http://eaavideo.org/video.aspx?v=784777819001 http://bcove.me/5dbxoeg9 Sid Wood Tri-gear KR-2 N6242 Mechanicsville, MD, USA It's been a while since this subject came up, but I've had two flat tires on landing due to a pinched tube, .-- Mark Langford --
KR> Tire pressure and Slime/Nitrogen
The reason nitrogen is used on planes is that heat does not effect pressure. We use it to pressure test hvac systems. I can charge it with 350 lbs at 10 o'clock and 80* outside an come back at 4 when it is 105* and it will have the same pressure. Aircraft use it because tires do not expand when filled with nitrogen. My struts take nitrogen if you use air the strut will very in length when temp changes. Sent from my iPhone > On Sep 11, 2016, at 9:47 PM, Jeff Scott via KRnet > wrote: > > > Of course compressed air is 78% Nitrogen. You use nitrogen on struts because > it's dry so you don't add moisture to the strut. Nitrogen in tires is mostly > a waste of money for tires since some moisture and 20% other gasses included > aren't going to make much of a difference in the leakage rate. > > -Jeff Scott > > > > > Nitrogen is supposed to be better to not slow leak because the molecules > are bigger than regular air. I always took that with a grain of salt > thinking how much of a difference can it make. > > A few months ago I helped a neighbor rebuild the nose strut on his 172. > He wanted to fill it with nitrogen instead of regular air, but our > friends nitrogen bottle was empty. I have a CO2 bottle with a regulator > for portable use of air tools and figured that would be as dry as the > nitrogen and just as good. We filled the strut and the next day it was > empty. Did it again and same results. Googled and found that CO2 has > molecules smaller than regular air so we filled it with air and it has > been good since. > > So, how much slower would nitrogen leak than air, no idea, but worth a > try. Airline tires are filled with nitrogen for less leakage, more > convenient on the line to roll out a nitrogen bottle than a compressor > that can go to a few hundred PSI, and less expansion at high > temperatures. > > > Original Message > Subject: KR> Tire pressure and Slime > From: Mark Langford via KRnet > > > I put all new tubes and tires on 1JF when I refurbed it, and it's had a > slow leak ever since on one side. About a month ago I put some Slime in > it, and it's still holding 50 psi. Something to consider. > > > _ > > ___ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org
KR> Gathering update
Speaking of "root beer", I will secure two cases of "root beer", one light and one dark, tomorrow to be used for refreshments at the camp site. I also secured a donation to cover most of the cost of the price kick for the steaks. I hated to tell Donny no as we are his favorite group and he wanted to go all out for us. Anyway, the cost is not an issue, just don't belly ace to me that your steak wasn't done EXACTLY the way you like it. Eat it, like it, and have a good time. :-) You will be asked when purchasing your banquet ticket if you request a steak or just the buffet to give Donny a count to toss on the grill. See you soon Larry Flesner
KR> Tire pressure and Slime
Sid Wood wrote: > Dick specifically shows how to avoid pinching the tube on the > split rims. No need for slime. I'm quite aware of how to assemble a tube into a tire with loads of talc to avoid a pinched tube. I haven't pinched a tube yet, and I've replaced 16 tires on the KRs so far, usually reusing the tubes. As I said in my post, I learned the secret to avoiding pinched tubes (after initial installation) is to keep them aired up to above 25 psi (or avoid really hard landings). I added Slime to that tube because it had a slow leak and over a month it would drop down from 50 to 25 psi, and become susceptible to pinched tubes again, and the Slime put an end to it without me having to take the tire off and replace the tube. With this ancient brake setup, removing the wheel is a huge pain the the butt and would take at least an hour, not to mention jacking up the plane, which I don't like to do either. I started putting Slime in my mountain bike tires about ten years ago, after picking up a thorn or two every year and having to patch a tube on the road or walk home to get the truck. I put Slime in those tubes ten years ago, and haven't had a flat tire since...nor do I need to top off the tires nearly as often. My apologies though...I should have kept that to myself, rather than concern the list with it. Mark Langford ML at N56ML.com http://www.n56ml.com
KR> Tire pressure and Slime
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