Scott 3200 high speed shimmy

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Re: Scott 3200 high speed shimmy

Post by 7698 »

Having looked at the images for the single and double bend spring sets, I'm opting for the single with my 3200...

Question. The very top section of the spring set has a small up-turn. Which way should this up-turn face? upwards or down against the second spring?

Many thanks.
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Re: Scott 3200 high speed shimmy

Post by 6597 »

Upward, away from the spring sets.
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Re: Scott 3200 high speed shimmy

Post by 8434 »

Hi All,

Lots of helpful info here, I especially appreciate David Sbur's picture comparisons of the two spring styles.

I don't have a high speed shimmy, but I do have a tailspring that isn't correct. My spring doesn't appear to have any bend, and has 2 leaf's that extend all the way to the tailwheel attachment. I have removed the spring set and refurbished it, including the bushing and rubbers (thanks Neil Wright articles). I'm now thinking of replacing the spring set with new. I just can't decide which one to replace it with.

Since my existing springset has no bend, and I have no shimmy, perhaps a single bend is best to preserve angles. However I'm number 14524 so I fall into late model and springsets with 2 bends. Perhaps the new springset will be softer, therefore sit lower and require an additional bend.

Does anyone have any recommendations?
MVIMG_20200402_162242.jpg
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Re: Scott 3200 high speed shimmy

Post by 6643 »

Danger Will Robinson! You cannot have a bolt through both ends of a pair of springs. When the springs flex they act as a shear on the bolts!
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Re: Scott 3200 high speed shimmy

Post by 8342 »

You need to look at the IPC (figure 23) showing the correct oriantation of the the two bolts (Item 23-52) holding the bracket.
They are supposed to be with the nuts up.
I know it is not normal but it is normal for this airplane.
And John is correct, the bolt should only go through one spring at the end holding the tailwheel on.

Rick
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Re: Scott 3200 high speed shimmy

Post by 8434 »

I agree with both of you.

This was the pre-refurbish picture and why I want to replace with new. The bolts are now upside down so they don't catch on the steering chains.

I can't even find where the spring came from, I looked at 170s but non have dual springs.
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Re: Scott 3200 high speed shimmy

Post by 6643 »

8434 wrote: Mon Oct 17, 2022 5:41 pmI can't even find where the spring came from, I looked at 170s but non have dual springs.
They can't. Either the springs won't flex or the bolts will shear. I think the only thing saving you from that fate is the rubber bushing on the top bolt. It must allow enough relative movement to prevent the bolt from breaking. None the less, I suspect if you dropped the tail in hard enough it would still break something. I think what you have there is two bottom leaves.
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Re: Scott 3200 high speed shimmy

Post by 8434 »

It's been this way a long time. Perhaps laminating the springs together resulted in a very stiff spring and there just isn't enough force to bend and shear.

Anyway, I don't want to find out what happens when something breaks.

I think I'll order the double bend so I comply with the parts book.
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Re: Scott 3200 high speed shimmy

Post by 2356 »

I have a double bend set. They have about a 100 hours on them. $75 + shipping.
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Re: Scott 3200 high speed shimmy

Post by 6643 »

8434 wrote: Tue Oct 18, 2022 12:39 pm It's been this way a long time.
Take a look at the bushing on the upper bolt. I suspect it's been taking the brunt of the shearing action. Also a close look the tail wheel bracket for cracking...
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