Welcome! Becoming a registered user of ShortWingPipers.Org is free and easy! Click the "Register" link found in the upper right hand corner of this screen. It's easy and you can then join the fun posting and learning about Short Wing Pipers!

Thanks Thanks:  0
Likes Likes:  0
Results 1 to 8 of 8

Thread: Tail Spring Arch Template

  1. #1
    Administrator Steve Pierce's Avatar
    Join Date
    Nov 2007
    Location
    Graham, Texas, United States
    Posts
    11,958
    Post Thanks / Like
    Blog Entries
    1

    Default Tail Spring Arch Template

    From Andy Anderson:

    The Tail Wheel Spring Template available here is one I used to obtain more correct caster to the tailwheel on my Piper PA-22/20. A good spring shop can accomplish the re-arching using this template. The template was drawn from a rearched spring leaf, the lower of the four leafs in the PA-20 spring set. The arch was traced along the upper surface of this leaf. The other three leafs of the spring were patterned after the the bottom leaf after it was re-arched. When the spring shop is re-arching the other leafs, it is important that he match the arch of the lower spring as they are positioned with reference to the fuselage mounting hole ( the fwd hole ).A ruler scale was annotated on the original tracing to assist in getting the correct size print out to use as a template. You will likely have to blow up the "jpg" file by some amount to get the ruler scale to line up with an acutal ruler. The other thing that could be done is measure the angle change between the fuselage mounting end of the tracing to the tail wheel mounting end. Make a template with a smooth curve such that the change in angle between the start and the end is similar to this sketch.The re-arching is done in a major size press. The spring leafs are placed in the press at various and evenly spaced locations along the leaf to get a smooth increase in the arc. The arc is changed gradually with each interation to produce a realatively smooth arch. The spring steel should not be heated as it will change the spring properties.tailwheelspringtemplate.pdf
    Last edited by Steve Pierce; 04-07-2012 at 03:13 PM.

  2. #2

    Join Date
    Jan 2011
    Location
    N. Seattle
    Posts
    41
    Post Thanks / Like

    Default Re: Tail Spring Arch Template

    Nice, thank you!

  3. #3
    Brian's Avatar
    Join Date
    Jan 2008
    Location
    Monrovia, CA
    Posts
    726
    Post Thanks / Like

    Default Re: Tail Spring Arch Template

    I have my tail wheel and spring off doing some routine maintenance as part of the annual on my 22/20, replacing some worn bolts and overall cleaning and re lubrication. So with the leaf spring off for the first time in a couple decades, the idea to have it re arched comes up. I have the 3 leaf PA-25 spring which agreed is different than what Steve used to trace the arch in the PDF. However to my surprise when I printed out this PDF and scaled it for the ruled dimension, the longer leaf in my 3 leaf set very accurately lays on top of this PDF print to great precision. So the question for the group is, am I good to go, or would a little more arch be desired ? The ABW spring is arched to a clearly greater degree than this and seems to be the cat's meow for those who have upgraded to it. I believe my castor angle is pretty level to the ground when the 22/20 is empty but would definitely have a negative castor heavy loaded. Advice greatly appreciated.
    Brian
    Monrovia, CA

  4. #4
    Lownslow's Avatar
    Join Date
    May 2009
    Location
    Victoria, Texas
    Posts
    758
    Post Thanks / Like

    Default Re: Tail Spring Arch Template

    Brian, I would say that if you track good and you don't have shimmy, it's like "if it ain't broke, don't fix it". Shimmy is not only aggravating, but also wears out your tailwheel. So if you don't have it, you are likely OK.

    Lou

  5. #5
    Administrator Steve Pierce's Avatar
    Join Date
    Nov 2007
    Location
    Graham, Texas, United States
    Posts
    11,958
    Post Thanks / Like
    Blog Entries
    1

    Default Re: Tail Spring Arch Template

    I agree, "if it ain't broke don't fix it."

  6. #6
    Brian's Avatar
    Join Date
    Jan 2008
    Location
    Monrovia, CA
    Posts
    726
    Post Thanks / Like

    Default Re: Tail Spring Arch Template

    Quote Originally Posted by Steve Pierce View Post
    I agree, "if it ain't broke don't fix it."
    Yes I'm basically in that school of thought myself. This topic has gone "shortwing" viral however and I've had more than one shortwing enthusiast tell me I should really consider getting my TW spring re arched while visually ramp checking my TW.
    Brian
    Monrovia, CA

  7. #7
    Gilbert Pierce's Avatar
    Join Date
    Nov 2007
    Location
    Germantown, Tennessee 01TN
    Posts
    3,093
    Post Thanks / Like

    Default Re: Tail Spring Arch Template

    If it does not shimmy, why bother. The only reason you would increase the arch is so it won't shimmy. It works, leave it alone.

  8. #8

    Join Date
    May 2019
    Posts
    8
    Post Thanks / Like

    Default Re: Tail Spring Arch Template

    Had shimmy problem on my 1953 PA-22/20-135 since I bought the plane 2 weeks ago. Took leaf springs off, re-arced using the above template. Actually went slightly more than the template to allow for some loading and settling back. Cleaned, re-lubed pivot point and axle with AeroShell 5, painted spring leafs and mounting brackets/clamp. Assembled and taxi tested, flown yesterday. Hurrah, no shimmy! Thank you Andy Anderson.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •