VansAirForceForums  
Home > VansAirForceForums

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

- Today's Posts | Insert Pics

  #1  
Old 12-02-2017, 05:57 PM
Vantastic12 Vantastic12 is offline
 
Join Date: Feb 2015
Location: Pagosa Springs Colorado
Posts: 9
Default RV-12 Wheel Camber

Greetings RV-12'rs:

Question please, I'm already having trouble severely wearing the outside of my new main gear tires after only 50 hours of taxi, take-off and landing time. In checking the KAI manual it only discusses toe-in/toe-out adjustment, nothing on camber. My toe-in/toe-out is neutral. In measuring the camber I'm seeing 6.9 degrees from vertical on the left wheel and 5.8 degrees on the right wheel, very obvious from just looking at the main gear on the ground. By comparison, my hangar partner's RV-8 tail-dragger only has apx. 1.5 degrees camber on both wheels.

Also, 28 PSI tire pressure per the manual seems low, also causing excess wear on the outside of the tires. I'm seeing no wear at all on the center of the treads yet.

How does this camber compare to yours and are you maintaining only 28 PSI in your tires? The only fix I can think of is adding shims B/T the lower gear legs and the axles to remove some of the camber, and increasing the tire pressure. Other ideas? I'd appreciate your response.
Reply With Quote
  #2  
Old 12-02-2017, 07:25 PM
Piper J3's Avatar
Piper J3 Piper J3 is offline
 
Join Date: Nov 2014
Location: Hinckley, Ohio
Posts: 729
Default

See photo below… I don’t have software tools but maybe someone can measure camber angle with respect to hanger floor. I installed Dresser 500-5 6 PLY AWBS RETREAD, ELITE PREMIUM 2 GROOVE (ELITE) 120 hours ago with lots of take off / landings on hard surface. Tires show very little wear.
-
__________________
-
Jim Stricker
Hinckley, Ohio
P/ASEL 1970 Sport Pilot since '04
80 hrs Flying Aeronca Chief 11AC
1130 hrs Flying 46 Piper J-3 Cub
LSRM-A Certificate 2016
RV-12 E-LSA #120058 AWC 7/12 Bought Flying 10/15 with 48TT - Hobbs now 317
Reply With Quote
  #3  
Old 12-02-2017, 08:11 PM
Nedimbek's Avatar
Nedimbek Nedimbek is offline
 
Join Date: Nov 2015
Location: Calgary, Alberta
Posts: 58
Default

Quote:
Originally Posted by Piper J3 View Post
See photo below… I don’t have software tools but maybe someone can measure camber angle with respect to hanger floor. I installed Dresser 500-5 6 PLY AWBS RETREAD, ELITE PREMIUM 2 GROOVE (ELITE) 120 hours ago with lots of take off / landings on hard surface. Tires show very little wear.
-
That is about 5 degrees with +/- 0.5 degrees error imho.
__________________
Nedim Bek
Reply With Quote
  #4  
Old 12-02-2017, 08:27 PM
rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
Posts: 7,049
Default

Quote:
Originally Posted by Vantastic12 View Post
Also, 28 PSI tire pressure per the manual seems low, also causing excess wear on the outside of the tires. I'm seeing no wear at all on the center of the treads yet.

How does this camber compare to yours and are you maintaining only 28 PSI in your tires? The only fix I can think of is adding shims B/T the lower gear legs and the axles to remove some of the camber, and increasing the tire pressure. Other ideas? I'd appreciate your response.
Keep in mind that it is a light airplane.
There is quite a bit of difference in camber at light solo weights versus gross weight.

Higher tire pressure wont change the zone where your tire is wearing at all, but it will put you at a higher risk for airframe damage in real hard landings.
__________________
Any opinions expressed in this message are my own and not necessarily those of my employer.

Scott McDaniels
Hubbard, Oregon
RV-6A (aka "Junkyard Special ")
Reply With Quote
  #5  
Old 12-02-2017, 08:31 PM
vernon smith's Avatar
vernon smith vernon smith is offline
 
Join Date: Jun 2017
Location: Naples FL
Posts: 104
Default

OneCNC CAD-CAM will trace an image by putting it on the screen and the user places points on the image as close to the desired image pickup points as possible. Imperfect at best but good enough for this. I used the exposed tire tread which was rather short but I thought better than the wheel pant side since there is not a flat area anywhere on it.

Unfortunately, the original image does not come with the OneCNC created .jpg image so you will have to take my word for it's accuracy.



Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

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 05:24 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.