tailwheel spring loose fitting with Scott 3200 assembly

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sanships
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Joined: Thu Sep 25, 2003 5:38 am

tailwheel spring loose fitting with Scott 3200 assembly

Post by sanships »

In my continuing saga in rbuilding my 52' 170b, my mechanic recently fitted the new tailwheel spring from aircraft spruce and the scot 3200 assembly together. It is showing that the tailwheel assembly is about 1/4" too wide for the spring and will need a spacer to connect properly. What is wrong with this setup? Did I buy the wrong spring or tailwheel assembly?

Thanks

Alvin Sandoval
Alvin Sandoval RPVM Cebu, Philippines
1952 170b, RP-C399, SN. 25287
2001 Robinson R22BII
zero.one.victor
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Joined: Tue Apr 23, 2002 12:11 am

Post by zero.one.victor »

JUst checked my Spruce catalog,it sez the Scott 3200 is for a 1-3/4" tailspring. I believe the 170 has a 1-1/2" tailspring. I checked my 1949 Scott 3200 170 installation drawing,they call out a 3241-3A spacer in between the t/w and the tailspring. The Spruce catalog lists a 3241-3S spacer for $44,that must be the 2004 equivalent. I'd double-check with Spruce or maybe direct with Scott (via website,if they have one?) before ya order the spacer,though.

Eric
N170BP
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Post by N170BP »

A spacer is indeed required to mount the Scott 3200 onto the
stock 170 tailspring assy. If I'm not mistaken, you can also
get these from Sacramento Skyranch.... (amongst numerous
other sources).

Bela P. Havasreti
'54 C-170B N170BP
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GAHorn
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Post by GAHorn »

I have an extra one you an have for the postage. PM me.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
zero.one.victor
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Joined: Tue Apr 23, 2002 12:11 am

Post by zero.one.victor »

It's been a while since it was off,but I seem to recall an extra spacer in the assembly,made of thin shim stock. Must be that there was still some slop even after the 1-3/4" to 1-1/2" spacer was installed. don't remember of it's between t/w casting & scott spacer,or between scott spacer & taailspring.
Anyway,make sure everything fits snugly,you don't want the parts slopping around.

Eric
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Curtis Brown
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Post by Curtis Brown »

I just ordered the tailwheel springs from Spruce. There are 5 springs and a main springs. Why are they different from what I have now which is a main spring and 3 others. Who is the supplier for the exact spring set up I have now? Or will these springs work?
Curtis
1950 A model 1256D
doug8082a
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Post by doug8082a »

The five spring stack is for the 170, the 170B (and I believe the A) use the 4 spring stack. Just throw out the top-most short spring and use the rest. It's easier and cheaper for companies (Univair, I assume, in this case) to just stock one part number for the whole assembly than to have two separate parts in inventory (a 4 and a 5 piece stack). There's more demand for the 4 piece assembly since more of the 170s use it, but there is *some* demand for the 5 piece assembly so they can't NOT stock it. Rather than have excess inventory of an assembly that has low demand, they just have a "one part number fits all" approach. They are identical except for the extra short spring on top of the 5 piece stack.
Doug
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GAHorn
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Post by GAHorn »

Are you sure you need anything more than just the mainspring? Almost nothing ever goes wrong with all the others anyway.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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rupertjl
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Post by rupertjl »

I just got done fixing the tailwheel in N9191A. The guy I bought it from was flying without that spacer and the tailwheel assembly was pivoting in the 1/4" gap allowed without the spacer. I bought one from Spruce and other than the thing costing me $95 which I could have made on the milling maching in 10 minutes myself, it works great. No more slop in the tailwheel assembly.
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Curtis Brown
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Post by Curtis Brown »

I replaced the main a few years ago. I thought I would order the springs to see if that would change the way my springs are attached. After looking at other 170's I noticed that my springs seem to be attached in the tail cone allowing about an inch or two of length coming out just before the angular bend. I noticed with the other 170's that the springs were all the way up into the tailcone to the bend. Also my tail seems to sit a little low. I am doing some tail wheel repairs anyway.
Curtis
1950 A model 1256D
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