Camloc

[verymadmac]

I am designing an engine cowl and the associated attachments for a small turbo prop aircraft.

In some places it will be attached with Camloc's. There is very little about on the pros and cons of the 2700 series and the 4002 series. Within the 4002 series there is the swaged retained grommet and the ring retained grommet. Having picked the brains of my usual sources there hasn't been as much insight as I would like as to which one works best.

Having reviewed all that I can find, the stack up will be a swaged grommet (40g15 series) and the skybolt adjustable depth receptacle (SK215 series) which then means a single stub length is required.

Has anyone found any pitfalls with using swaged grommets or the skybolt adjustable depth receptacles?

 

[Sparweb]

I'll try to start the ball rolling-
I've used Camloc's and related types only a handful of times. So far only on interior panels not exterior ones, so I am sorry I can't say anything about weather resistance, corrosion resistance, or anything else about environmental sealing. Since you are going to use these on a nacelle fairing, I think a major consideration will be resistance to effects of vibration. If there's a gasket around the lip of the fairing seam (as I would expect) then there will be a pre-load on the Camloc's which should help keep them closed, but the devil's in the details getting the pressure just right.

Are you sure Camloc's are the right fastener? Thinking of the King Airs and Twin Otters that I hung around, I don't think they use Camloc's at all, except maybe for the small access panels for oil etc.
Look at Hartwell, Actron, and maybe Southco, who have alternatives you could consider.

STF

 

[verymadmac]

The cowl does have the caravan style barn doors with a couple of latches. The camloks are for attachment to the firewall and joining the fixed cowl pieces.

Can't say I like the typical Hartwell style latch they have a tendency to cause damage if there is any miss alignment, in difficult to repair places (at least they do on the metro cowls) . On this project they are out of consideration on lead time, cost, etc.

 

[WKTaylor]

For What You are describing, I prefer using structural panel fasteners. In my humble opinion these are stronger, stiffer/tighter and far more reliable than Camlocs...

REF MIL-HDBK-271-106 STRUCTURAL PANEL FASTENERS-INSTALLATION AND REMOVAL METHODS FOR MIL-F-85616, MIL-F-85617 AND MIL-F-85618

NASM1312-26 FASTENER TEST METHODS METHOD 26, STRUCTURAL PANEL FASTENER LAP JOINT SHEAR

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true.
o For those who believe, no proof is required; for those who cannot believe, no proof is possible.
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion"]
o Learn the rules like a pro, so you can break them like an artist. [Picasso]

 

[tbuelna]

While you may not like the substantially higher price of panel latching hardware from Hartwell versus the Camloc hardware you noted, there are very good reasons for using the more costly latching hardware from Hartwell (and others) for certain applications. For example, the Hartwell panel latching systems typically don't require any tools to operate, and they also provide a visual indication of whether they are securely latched or not.