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mvanover
PostPosted: Wed May 06, 2020 10:25 am 
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We have a Maule tail wheel and flat spring set-up on our Thorp. It is very twitchy on the ground and probably isn't set up right to begin with. I'm interested in the Aviation Products tail wheel and spring, but I don't know which ones would be the best set up. I think the 6" wheel would be more effective and I'm not concerned with the size. What I would like is something that is responsive yet stable. I'd like to try the rod spring set up, but don't know how it is secured to the airplane. I assume that I'd have to make a custom part to accept the rod and still be able use the original attachment bolts. However, I don't have any machining capability. So, perhaps a flat spring would be the easiest way to go. But which one? I don't think the original springs would be any improvement. I know there are other solutions and I'm open to them. I'm just looking to improve the ground handling of the airplane. Any suggestions or information about this would be appreciated.

Marty Vanover
Tucson, AZ.


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Ryan Allen
PostPosted: Wed May 06, 2020 12:32 pm 
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I have the Aviation Products tailwheel. I believe its (on the Aircraft Spruce website) the 10° Angle for 5/8 round spring P/N 06-06135. I feel like you could buy the collar from Thorp Central, but any machining on the rod, I have no idea there.


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fytrplt
PostPosted: Wed May 06, 2020 12:37 pm 
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Location: Lakeland, Florida, USA
You need to be able to drill four accurate holes in steel to install.

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Jim Mantyla
PostPosted: Wed May 06, 2020 1:38 pm 
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Joined: Wed Oct 21, 2009 6:57 pm
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Location: Barrie, Ontario,Canada
mvanover,

I have the trusty spring which I believe is the same as the one you are looking at. I also have the aviation products double fork on the end with a Matco 6" solid wheel. The Matco wheel is a lot lighter than the cast steel one supplied with the fork. It was well worth the switch. It's not a bouncy and directional control really improved. The other bonus is that it lowered the tail a bit as well.

When I got my tail fork, I noticed that it released at about 20 degrees of movement either way. The rudder moves 30 degrees each way. I did modify this so that the wheel does not release until the rudder has hit the stop.

Regards,

Jim


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James Grahn
PostPosted: Wed May 06, 2020 8:26 pm 
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Joined: Sat Oct 24, 2009 7:16 pm
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We sell the Trusty spring, collar, spacer and tail wheel. I recommend the six inch double fork. Unfortunately we are currently waiting on more Trusty springs. But we have all of the other components. We also sell a complete kit where you unbolt what you have and bolt these parts on. As Bob said, some drilling is required to make sure it fits your bird exactly.
Having said all that, I believe you have an alignment problem. Any airplane, especially a tail wheel one, will be a handful if not set up properly. I’d have to look, but I think I wrote a paper that is on this site somewhere for how to align your bird. I strongly suggest you start there. If you still want to swap springs, let us at Thorp Central know.
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James Grahn
PostPosted: Wed May 06, 2020 8:27 pm 
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We sell the Trusty spring, collar, spacer and tail wheel. I recommend the six inch double fork. Unfortunately we are currently waiting on more Trusty springs. But we have all of the other components. We also sell a complete kit where you unbolt what you have and bolt these parts on. As Bob said, some drilling is required to make sure it fits your bird exactly.
Having said all that, I believe you have an alignment problem. Any airplane, especially a tail wheel one, will be a handful if not set up properly. I’d have to look, but I think I wrote a paper that is on this site somewhere for how to align your bird. I strongly suggest you start there. If you still want to swap springs, let us at Thorp Central know.
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Terry Adams
PostPosted: Wed May 06, 2020 10:37 pm 
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Joined: Sat Oct 31, 2009 12:22 pm
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Location: Stockton, CA USA
I would suggest checking the vertical plum line of the tailwheel pivot which could be affected by your particular spring. Our plane had the Maule single fork tailwheel, flat spring, and solid Maule tire. The rubber tire eventually failed. Upon sound advice from others espousing the potential failure of the single arm of the Maule I installed the ACS double fork. The plane became squirrely on the ground. Upon checking I discovered the tailwheel pivot was not perfectly plum (raked forward IIRC). I pulled the ACS double fork, reinstalled the Maule single fork, installed the ACS solid rubber tire on the Maule single fork, and lived happily ever after. YMMV
ACS double fork tailwheel for sale at a good price.

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Jeff J
PostPosted: Thu May 07, 2020 5:12 pm 
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Location: eastern OK
I am running the ACS double fork tailwheel with the original flat spring. It can be pretty bouncy but hasn’t ever shimmied on me even though the pivot isn’t plumb.

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mvanover
PostPosted: Fri May 08, 2020 7:23 pm 
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Joined: Tue Oct 22, 2019 2:52 pm
Posts: 14
Terry,

I'm interested in the tailwheel fork. What spring angle is it? Is it for 1-1/2" spring or rod type spring. You can e-mail me at the following:

martin.m.vanover@gmail.com

Thanks!

Marty Vanover
Tucson, AZ


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