Help sourcing these parts

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Flow

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Hey folks, I need a bit of help sourcing the parts in the photo.

I have found the little top hat nylon washers, they are from an Alpi 200 canopy.
The 10/32 SS dome head machine screws are OK but the chamfered edge (flying saucer style) nylon washers are very hard to find. Any thoughts?
The rolled steal crush washer is also difficult to source.
20210621_091032.jpg
 

Flow

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Any ideas, which aircraft, if any, use a bunch of 10/32 screws to secure the cowl?
 

TFF

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I have never seen the one with the collar made on, so it’s probably custom hardware. The regular is pretty easy to find.
 

Flow

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Found the collar one, just looking for the regular one. Not seen any with the top side edge chamfer ?
 

rv7charlie

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It's all in your google-foo.

Here you go...

edit: You might need to be more specific on the crush washer. Application?

edit2: Shoulder washers are common as dirt in electronics, where power transistors need to be insulated from their heat sinks.
 

Aviacs

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On a more serious note,

top hat nylon washers
Is nylon superior for that app, as opposed to say, delrin, or ultem? Or just cheaper?
If a person was to make a pile of them as part of a canopy retention scheme, say?

smt
 

Derswede

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Try some of the guys who make windscreens for motorcycles, those look like the screws that are used on my Rifle screen for my Triumph.

Derswede
 

rv7charlie

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... steal crush washer is also difficult to source
kind of self explanatory.

smt


So, if it's so self explanatory, where do you steal them?

Yeah, 'steel crush washer' defines itself, but knowing the application just might make it easier to help the OP locate a replacement.
(BTW, thanks for explaining the obvious; we were so challenged....)
 

Hephaestus

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The nylon part - you could get 3d printed...

There's a couple Taulman nylon filaments that print at 230deg - so any standard 3d printer would be able to do it. Or spend some bigger $ having them printed on a commercial SLS machine. Given the size, even in SLS they'd be fairly inexpensive.
 

Aviacs

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So, if it's so self explanatory, where do you steal them?
If someone steals them they are always gone by the time you get there.
Unless the stealer approaches you on a job...psst....etc, etc

Hat washers could be a turret lathe job.
I just bought the remaining stock from the estate of a guy who was running 3 AHC's with barfeeds on plastic parts.
My Q about materials includes the consideration that nylon is one of the more hygroscopic plastics, and will shrink & swell almost like wood, though to much smaller extremes. OTOH. perhaps it has some other characteristic that is desirable, or maybe just relatively low cost?

What size is the crush washer?
What material (alloy) & condition (hardness/normalization/etc?
What purpose?
 
Last edited:

BJC

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Any ideas, which aircraft, if any, use a bunch of 10/32 screws to secure the cowl?
I just reinstalled my cowling, using 34 each 10-32 screws. There are more in the nose wheel and gear leg fairings. Glasair Aviation Sportsman 2+2.


BJC
 

Flow

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Apr 27, 2016
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Auckland
BJC, did yours have washers?
I have found a place that can make the chamfered edge plain washers. Still interested in where they are commonly used though.
Top hats are sorted
Just leaves the steal crush washers, for a cylinder head gasket. I am looking to spec them slightly thicker.
 
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