Common hardware for 170s

How to keep the Cessna 170 flying and airworthy.

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Jtramo
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Joined: Thu Aug 14, 2014 2:38 am

Common hardware for 170s

Post by Jtramo »

I’m trying to build up a supply of hardware for my owner maintenance purposes and even some heavier A&P assisted type stuff. Short of just ordering a 170 exterior hardware kit what other types of common AN type hardware/cotter pins etc should I stock up on? So far I’ve had to find a single rear seat bolt that’s been missing for idk how long and i dropped and lost a carb base nut. The older manuals don’t seem to always have AN part numbers for hardware. Thanks!
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Bruce Fenstermacher
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Re: Common hardware for 170s

Post by Bruce Fenstermacher »

If the manual does not call for AN hardware, it is because it may not be AN hardware. For example there are many nuts and bolts on the engine that look like AN hardware, but are made to Continental specification. Many times this is a slightly different grip length or maybe a special washer. However in some of these cases, as time has gone by, the part number for that piece of hardware will be superseded to AN or MS hardware.

Don't go nuts buying hardware. You will always have the wrong thing on hand. I would not buy a exterior "hardware kit" if there is such a thing for a 170. I would buy a selection of PK screws like you see on your cowlings and fairings, some washers, thick and thin, some nuts, castle, plain and lock type as well as some cotter pins all for AN3 and 4 bolts. These are the things you are likely to drop and lose. Some .032 safety wire is always handy to have not necessarily to wire nuts and bolts.
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GAHorn
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Re: Common hardware for 170s

Post by GAHorn »

+1 w/Bruce

I’ve yet to see an “exterior hardware kit” for any model airplane which was actually/adequately applicable to that airplane. The so-called 170 set had extraneous screws which were never used, and insufficient numbers of other sheet metal screws. That’s not to say those kits aren’t a good place to start a collection tho’... PK screws and such are always needed in great numbers.
The stainless steel kits are particularly frustrating if you are looking for “structural” hardware tho’. Beware that most such kits are actually not appropriate for structural use...only for fairings and cowlings....and stainless screws are particularly susceptible to damaged threads. They wear out quickly due to vibration when installed in steel “tinnerman” style receptacles.
A good selection of AN hardware is difficult to assemble. I personally have a dozen or so of each common AN size castellated, plain, and fiber/nylock nuts in 3,4,5,6,7 sizes and flat, thin, star, and split washers. A good look at the IPC will give you an idea of what corrosion-resistant hardware to have on hand for your exhaust system. (They should be closely examined at each annual at least.)
You can spend $500 very quickly if you are trying to have “on hand” whatever you need all the time out in the boonies.
Overnight freight of the exact item from aircraft suppliers are cheaper than that unless you are a shop or regular mx guy.
'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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