The International Cessna^® 170 Association

Presently going through the anual a crack on one of the spinner screw holes was found. My A&P says it can't be repaired so he suggested buying a composite made spiner. It is FAA aprooved and costs only 320 aproximately compared with the Cessna original of 700. I saw a couple aluminium in aircraft spruce catalog FAA aprooved . One for 310 and the other for 400.

I don't think buying a used one is an option as it is probably cracked or just about to get there.

Please send your comments,

Victor

At Wag-Aero you can get a new aluminum spinner with the backplate for $255. I would have to wonder how long a composite would last.

http://store.wagaero.com/*ws4d-db-query ... ts(S).html

or

1-800-558-6868

I have the one from a/c srpuce on mine. As I recall, it is a Univair part marketed by spruce. It's been fine these last four years.

Victor, if you aren't aware, many of WAG's items aren't FAA/PMA approved. Be sure to watch the code on their items. I notice on the internet site that this spinner & backing plate is a code 2 (not approved), but in my latest WAG catalogue (January 2004) it shows to now be approved.

I bought one just like this for my plane when I did my overhaul as my backing plate was badly cracked (no repair) & it is a good unit.

Good luck!

Victor my friend does still have the spinner I PM'd you about. He does not have the back plate if that is what you need, just the spinner. PM me if you want to investigate this further.

There may be a new spinner in my future as well. I have a small crack emanating from one of the screw holes that a previous owner stop drilled. I have not had a mechanic say anything about it yet, but if I have to replace it I would like to do it before I paint the airplane, which I am close to doing. One alternative will be replacing with a polished spinner, as opposed to one painted to match my stripes.
Are the polished spinners any different, or are they just that, polished?
David

David

I like polished spinners, perhaps because I miss polishing my 195! (not really, but once in a while I miss the 195 )

To properly polish a spinner you need to sand out the turning marks from the surface. I take them out with 150 grit then as they start to dissapear work progressively to 320 or 400. At that point I put it on my polish wheel that's on a large slow moving grinder on a stand. If you sand it out any chrome shop can do the final polish for you but don't let them polish it without sanding it first, they'll hammer it.

BTW, chroming a spinner is not recommended.

I stipped my spinner of the paint and sanded it. I did not chrome or repaint it and it looks pretty good after polishing with Flitz. My prop is polished also. The plane is at the paint shop now being painted but I intend to leave spinner polished.

An economical alternatve might be a skull-cap spinner instead of the bullet style. My Spruce catalog shows the 170 bullet spinner at $269 & the complete assembly at $403-- a 6" skullcap & bracket are listed at $30. There is also a bullet spinner for $85,but it's a do-it-yourself on the blade cut-outs & screw holes.
The skullcap was factory original on the ragwings & at least some of the A's (I think),not sure about the B's. IMHO they don't look as good as the bullets,but some might think otherwise.

Eric

Talked to Wag-Aero today, the spinner mentioned above for $255 is now a code 4 (FAA/PMA approved), the web page had not been updated. They mentioned that they were trying to get a lot more of there parts approved as well. Until then, as mentioned, you best check.

Eric yes the 170A had a skull-cap spinner. That last 170B of mine had a large spinner. It looked nice but it makes it hard to reach the top cowling screws behind the spinner backplate. I used an angle-screwdriver to get to those.
Max

The big spinner's aft bulkhead also makes it hard to see the timing mark on the crank flange--I use a mirror & a little pointer device I made to line up the timing mark(s) & the crankcase seam.
Besides looks,I have heard people claim that the bullet spinner flows more air & therefore cools better than the skullcap. Sounds a little farfetched to me but who knows.....

Eric

78D has a skull cap, looks Ok! Have heard that the bullet spinners hide more flat frontal area, thus increasing speed. The timing marks are such that I have to use a mirror even with the skull cap.

I have a composite spinner on a 172 it has lasted just fine. I think that composite would last longer than aluminium. (not subject to fatigue cracks)
Plus polishing is a pain! !!

I installed nut plates on the outside of the cowl behind the large spinner on Hoog's 170 reversing the attachment hardware.(AN3 bolts) Now we can remove the cowling without removing the spinner. (it was impossible before.)

For timing I allways use a degree wheel, timing marks are never quite accurate.

Scott, what is it about Hoog's spinner that made it "impossible" to remove the cowling without removing the spinner? I"ve never had such a problem with any of the original cowls/spinners.