Good evening,
Took the 3200 apart and noticed it had all 5 springs installed. Additionally, the 3 posts were snapped loose from the (pressure plate?). I've looked at previous posts which indicate only 3 springs should be used on a 170(B). Would using 5 springs make it harder to steer the tailwheel?
KJM
Scotts 3200 3 springs vs 5
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- Bruce Fenstermacher
- Posts: 10318
- Joined: Tue Apr 23, 2002 11:24 am
Re: Scotts 3200 3 springs vs 5
5 vs 3 springs should not make it harder to steer IF you have the king pin nut adjusted so it doesn't. Resistance pressure is created by spring pressure, either 3 or 5 and adjusted by how tight the nut is on the king pin. Remember the Scott 3200 is an industrial castering wheel not necessarily designed for one intended use as a airplane tailwheel. It was apparently thought that 3 springs and average nut adjustment was right for a smaller lighter aircraft a category the 170 fits into. 5 springs is called for on a 180/185 and other heavier aircraft.
Without looking for specific instructions how to start adjusting the king pin, which I'm not sure exist, but I would look for anyway, I'd start where you think the wheel swivels nicely but with some drag. Fly the plane. If you get shimmy, tighten the nut a flat or 2 and try again. If not leave it alone or loosen a flat or 2 and try again. Of course doing this assumes you have a good mounting angle of the wheel which is dependent on the leaf springs. A tighter king pin adjustment can mask a bad mounting angle and a loose adjustment can make a mounting angle on the cusp of being bad, shimmy.
Without looking for specific instructions how to start adjusting the king pin, which I'm not sure exist, but I would look for anyway, I'd start where you think the wheel swivels nicely but with some drag. Fly the plane. If you get shimmy, tighten the nut a flat or 2 and try again. If not leave it alone or loosen a flat or 2 and try again. Of course doing this assumes you have a good mounting angle of the wheel which is dependent on the leaf springs. A tighter king pin adjustment can mask a bad mounting angle and a loose adjustment can make a mounting angle on the cusp of being bad, shimmy.
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Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
Re: Scotts 3200 3 springs vs 5
The Tyco Scott “ Shimmy Checklist” instruction sheet location in the maintenance section page 2 line 6 states “Castle nut torque ( both wheel and bracket) 15 inch lbs min then if required continue clockwise to access cotter pin hole.
I have 5 springs in my 3200 and I have one with 3 on the project.
I have 5 springs in my 3200 and I have one with 3 on the project.
- rschreiber
- Posts: 49
- Joined: Wed Dec 18, 2019 4:36 pm
Re: Scotts 3200 3 springs vs 5
I went from 5 to 3 springs at my last annual and haven’t noticed any difference.
Ryan
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- Posts: 16
- Joined: Fri Nov 20, 2020 8:59 pm
Re: Scotts 3200 3 springs vs 5
Thank you all for the responses!