How 'Dust Proof' are FWC

[jbahr]

OK but do you have specifics? I'm trying to get at the details of how they did that.


Whenever we have seen a crack in the frame, like what is shown in the first picture, it has always been at the weld that is noted in the second picture. The 1x1 tube at the top of the door opening no longer spans just the opening. Instead it now spans nearly the entire width of the camper. Additionally, the radius door no longer puts any stress directly at the corner because it is essentially open and allowed to flex.

 

[WaltK]

Whenever we have seen a crack in the frame, like what is shown in the first picture, it has always been at the weld that is noted in the second picture. The 1x1 tube at the top of the door opening no longer spans just the opening. Instead it now spans nearly the entire width of the camper. Additionally, the radius door no longer puts any stress directly at the corner because it is essentially open and allowed to flex.


I noted some about the aluminum frame around the door that probably contributes to the fatigue cracking when I first removed the old door.

The tubing is quite thin, so thin that even screwing in a sheet metal screw into it distorts it and pulls it out around the screw hole when the screw is tightened. That's a very good source of starting a fatigue crack, I wonder how many of those cracks originate at a screw hole? And the door is attached via screws into the 1x1 tube described. Yes the thinner curved top extrusion which is attached with only a few screws at the top probably helps to make fatigue less likely than it was with the heavier square top with it's frequent screws.

When I removed a piece of 1x1.5" square tube from where my propane storage opening is I could only get the saw at one end. A half dozen back and forth bends on the tube at the inaccessible end fatigue cracked the thin tube off next to the weld seam. That's how easy it is to fatigue crack.

Note where the skin is attached to the thin metal frame via staples the tube also distorts from the force of stapling...

 

[DirtyDog]

Thanks for the info!