VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > Model Specific > RV-12/RV-12iS
Register FAQ Members List Calendar Today's Posts

Reply
 
Thread Tools Search this Thread Display Modes
  #11  
Old 01-01-2015, 01:36 PM
RFSchaller RFSchaller is offline
 
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 2,820
Default

Walt,

Piper recommends 24 or 26 psi (would have to check my POH for which) for my Cherokee 180, so I never gave the RV-12 reassure a second thought. What was it that made you think that too low? I agree that in two months they'll be lower.

Rich
Reply With Quote
  #12  
Old 01-01-2015, 02:52 PM
Walt's Avatar
Walt Walt is offline
 
Join Date: Aug 2005
Location: Dallas/Ft Worth, TX
Posts: 5,686
Default

Quote:
Originally Posted by RFSchaller View Post
Walt,

Piper recommends 24 or 26 psi (would have to check my POH for which) for my Cherokee 180, so I never gave the RV-12 reassure a second thought. What was it that made you think that too low? I agree that in two months they'll be lower.

Rich
Well maybe just my experience, I can't think of a single flat I've seen/repaired that was caused by a puncture, its always some type of split in the tube which is "generally" caused by excessive flexing of the sidewall which can be attributed to low tire pressure. I have no objection to the manufacturers recommendation, but one must be diligent about maintaining specified pressures if you want to avoid problems (flats). If you get into that 15-20 range you are just begging for trouble.

On another note I wonder how many folks actually check their tire pressures every 30 days?
__________________
Walt Aronow, DFW, TX (52F)

EXP Aircraft Services LLC
Specializing in RV Condition Inspections, Maintenance, Avionics Upgrades
Dynamic Prop Balancing, Pitot-Static Altmeter/Transponder Certification
FAA Certified Repair Station, AP/IA/FCC GROL, EAA Technical Counselor
Authorized Garmin G3X Dealer/Installer
RV7A built 2004, 1700+ hrs, New Titan IO-370, Bendix Mags
Website: ExpAircraft.com, Email: walt@expaircraft.com, Cell: 972-746-5154
Reply With Quote
  #13  
Old 01-01-2015, 04:49 PM
DonFromTX's Avatar
DonFromTX DonFromTX is offline
 
Join Date: Oct 2010
Location: La Feria Texas
Posts: 3,822
Default

Why do they leak down so bad? My unfinished plane has never been out of the garage, and they lose air regularly, still have the stickers on them.
__________________
A&P, PP-SEL, Pathological Flier, EAA Technical Counselor
EAA Chapter 595 President,http://www.595.eaachapter.org/index.htm
Retired US Army Officer
Reply With Quote
  #14  
Old 01-01-2015, 05:07 PM
Sam Buchanan's Avatar
Sam Buchanan Sam Buchanan is offline
been here awhile
 
Join Date: Dec 2004
Location: North Alabama
Posts: 4,301
Default

Quote:
Originally Posted by Walt View Post
....If you get into that 15-20 range you are just begging for trouble......
On another note I wonder how many folks actually check their tire pressures every 30 days?
With our little 5.00x5 tires 15-20lbs looks FLAT! You would have to be very inattentive to let them get that low. Looking at the tires is part of the pre-flight, and it's possible to get pretty good at sensing low pressure once we have learned the plane. I keep 26-35 lbs in the RV-6 and (knocking on wood....) haven't had a flat in 16 years. More than 35 on the RV-6's springy gear is more harsh than I can stand.

My experience with leak-stop tubes has been that air needs to be added about every two months to keep pressure within 2-3 lbs of target pressure.

Quote:
Originally Posted by DonFromTX View Post
Why do they leak down so bad? My unfinished plane has never been out of the garage, and they lose air regularly, still have the stickers on them.
Don, you are probably seeing leakage from the original, natural rubber kit tubes which are quite porous. The "leak-stop" tubes are made of some sort of synthetic rubber (like auto and motorsickle tubes) which maintains pressure much better. You will want those tubes once you start flying.
__________________
Sam Buchanan
RV-6
Fokker D.VII replica

Last edited by Sam Buchanan : 01-01-2015 at 05:16 PM.
Reply With Quote
  #15  
Old 01-01-2015, 05:43 PM
PCHunt PCHunt is offline
 
Join Date: Feb 2007
Location: San Diego, CA
Posts: 1,670
Default

In addition to the already-mentioned leak-stop tubes, fill with Nitrogen instead of compressed air. It is alleged that the Nitrogen won't leak as much as plain air.
__________________
Pete Hunt, [San Diego] VAF #1069
RV-6, RV-6A, T-6G
ATP, CFII, A&P

2020 Donation+, Gladly Sent
Reply With Quote
  #16  
Old 01-01-2015, 06:00 PM
tboyett tboyett is offline
 
Join Date: May 2011
Location: Katy, TX
Posts: 39
Default

Quote:
Don, you are probably seeing leakage from the original, natural rubber kit tubes which are quite porous. The "leak-stop" tubes are made of some sort of synthetic rubber (like auto and motorsickle tubes) which maintains pressure much better. You will want those tubes once you start flying.
Are you referring to the LeakGuard tubes found at Aircraft Spruce or something else?

Thanks,
Tom
__________________
RV-12 E-AB N79AM completed
www.rv-12.blogspot.com
2016-17 VAF donation gladly made
Reply With Quote
  #17  
Old 01-01-2015, 06:10 PM
PCHunt PCHunt is offline
 
Join Date: Feb 2007
Location: San Diego, CA
Posts: 1,670
Default

Leak guard, leak stop, also found a Desser Tire.

http://www.desser.com/products_airtubes.php
__________________
Pete Hunt, [San Diego] VAF #1069
RV-6, RV-6A, T-6G
ATP, CFII, A&P

2020 Donation+, Gladly Sent
Reply With Quote
  #18  
Old 01-01-2015, 06:42 PM
rvbuilder2002's Avatar
rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
Posts: 9,035
Default

Leak guard style tubes have been standard in RV finish kits for quite a few years now.
__________________
Opinions, information and comments are my own unless stated otherwise. They do not necessarily represent the direction/opinions of my employer.

Scott McDaniels
Van's Aircraft Engineering Prototype Shop Manager
Hubbard, Oregon
RV-6A (aka "Junkyard Special ")
Reply With Quote
  #19  
Old 01-01-2015, 08:44 PM
Sam Buchanan's Avatar
Sam Buchanan Sam Buchanan is offline
been here awhile
 
Join Date: Dec 2004
Location: North Alabama
Posts: 4,301
Default

Quote:
Originally Posted by rvbuilder2002 View Post
Leak guard style tubes have been standard in RV finish kits for quite a few years now.
Thanks, Scott, glad to know they are part of the kit.

Another common cause of slow leaks is a valve core that is either not tight enough or defective. I've had to replace a couple over the years.
__________________
Sam Buchanan
RV-6
Fokker D.VII replica
Reply With Quote
  #20  
Old 01-01-2015, 09:40 PM
RFSchaller RFSchaller is offline
 
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 2,820
Default

I wonder if the tire spec for pressure is just the max they are rated for by the tire manufacturer as opposed to the recommended working pressure.

I had a bad stem valve on one tire that created a slow leak until I replaced the valve stem - saved some money and hassle there!

Maybe it's just me, but I find it tough to judge the tire pressure state by sight with the wheel pants installed.

Rich
Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 01:21 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.