Cowling fasteners

[markejackson02]

My 201 has the usual camloc studs holding the cowling on.  Some of them have a washer under them to increase the tension and prevent chaffing?  They came this way.

 

I cannot for the life of me figure out what kind of washer this is.  I have ordered practically one of everything Aircraft Spruce carries as well as Lowes.

 

Any idea what these washers are?

 

Thanks

 

Mark Jackson

 

 

[firefly201]

Mark, 

The washer you pictured I don't think is a Camloc part. Try looking  at Camloc grommets. There is a snap ring that holds the grommet in. There are two different sizes used on the J. Bigger across the top, philips head.  Smaller down the sides, mine were straight blade but I think philips would work too. Special tool to install grommets and snap rings.

[Guest]

Standard aircraft washers are AN960 series, hole diameter is calculated in 1/16" increments. The Camlocs which hold the cowl to the firewall flange are 4000 series and do not normally have an AN washer, but have a Camloc grommet which is secured to the cowl with a lock ring. The smaller Camlocs which fasten the top and bottoms are Camloc 2700 series usually held in place with a small Camloc split washer. In many cases the holes get worn and the fastener falls out.

Clarence

[M20F-1968]

Try looking at the SkyBolt fastener web site.  They have a 2000 series fastener which looks similar to this one.

 

John Breda

[DonMuncy]

It looks to me like a Camlock grommet. Check Aircraft Spruce.

[PLN_FXR]

Standard aircraft washers are AN960 series, hole diameter is calculated in 1/16" increments. The Camlocs which hold the cowl to the firewall flange are 4000 series and do not normally have an AN washer, but have a Camloc grommet which is secured to the cowl with a lock ring. The smaller Camlocs which fasten the top and bottoms are Camloc 2700 series usually held in place with a small Camloc split washer. In many cases the holes get worn and the fastener falls out.

Clarence

This looks like a 2700-series Camloc that someone has placed an AN washer under either to correct for too long a fastener, or to compensate for wear in the fiberglass cowl surface.  It's difficult to tell from your photo if the washer is slightly concave?  

[jetdriven]

Yah that looks like an AN-960-12L washer under the camloc. Just get some mil spec 2800 series fasteners if you need to cover a worn hole. The standard 2700 series camloc is 3/8" OD. The 2800 is the same fastener but 1/2" OD. Basically a bigger flange on the fastener. They get you by a few more years.

[markejackson02]

Sorry.  I had bought new camlocs, those are all fine.  It is the washer that I can't figure out. They aren't retaining washers that come with the camlocs.  These washers are much larger and thinner.  I have been able to find washers of the same diameter but they are three times as thick as the mystery washer.  I tried a grommet but these are flat washers, no lip on them.

 

Mark Jackson

[BigTex]

Have you reached out to some of the MSC's and asked them?  Might give Don Maxwell a call as I'm sure he'll be able to help you out.