Hangar Door Jam

JohnWF

Pre-takeoff checklist
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John at Salida
Took the plane out this morning for a short flight. Noticed an unusual noise as the bi-fold door opened...took plane out, and when closing the door it jammed. Found one of two cables had jumped off its pulley. After a bit a trying to move the door the other cable also jumped off its pulley.

Fortunately two friends were nearby and together we finally got the plane back in the hangar and after even more work got the door down (more of less free-fall into place.)

I will get new cables because they were kinked in the process, but cannot reach the pulleys because they are behind a large I-beam, so I will cut two small windows in the door at the pulley location and re-string new cables, then put window plastic over the cut outs. Lots of work, but it should be OK.

Its a Schweiss door that has been trouble free for a bit over 20-years. But for now the plane is stuck in the hangar...at least its out of the weather until I can get things fixed.
 
instead of cutting into the door, can you not just unscrew the exterior sheeting?
What will keep the cables from jumping off the pulley next time? Maybe a good time to look into pulley guides 'fairleads'.
 
Yes, it later struck me to do just that....un-screw panels...what are the pulley guides?

I suspect that after 20+ years the cables had stretched enough to allow them to slip out of the pulley groove.
 
Right, I don't think they should ever get completely slack. Pulley guides...you could buy from Grainger maybe, or a marine shop, or make your own. Look at your airplane for ideas, often they have some way to keep the cable where it belongs.
 
I will get new cables because they were kinked in the process, but cannot reach the pulleys because they are behind a large I-beam, so I will cut two small windows in the door at the pulley location and re-string new cables, then put window plastic over the cut outs. Lots of work, but it should be OK.

Its a Schweiss door that has been trouble free for a bit over 20-years. But for now the plane is stuck in the hangar...at least its out of the weather until I can get things fixed.

If at all possible, replace the cables with their straps.
 
You'll want to check the pulleys. After a period they will wear severely on the back side of the pulley and be as sharp as a knife. It might be best to just buy new pulleys while your buying new cables. Do not buy cable at home depot as it is most likely not the right size and configuration for your door. Get the style and serial number of the door and call Schweiss and buy from them. The cables you buy from them will most likely be cheaper than sourcing it somewhere else. The guides at the bottom are likely all bent up also and will need some straightening and the tubes in the guides probably have grooves cut in them. Replacing the cables is not a hard job at all. Good luck.
 
I'd recommend getting somebody experienced on working on those doors. Those doors have killed people. Seriously. I rented a hangar where the guy that built it was killed by his door. Hire someone that knows what they are doing.
 
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I am going to replace the cables with straps...will talk to Wchweiss tomorrow.

The door is securely attached to the frame...its just the lifting apparatus that is the problem.

Is there someone on here that has actually made this conversion? I would like to ask a few questions Thanks
 
Schweiss quoted me $3,960 to change to straps..they said the drive motor and reduction gear box would have to be changed...pressed for why? they said the diameter of the drive drum would be different and would take more power.

I really do not believe this..the door only cost $1,732 when purchased and has not gained weight so the lifting forces should be the same....???

I will secure replacement cables and fix it myself. Very disappointing.
 
My Schweiss door has no pulleys . The cables (4 of them) attach at the top of the frame and the drive shaft simply winds all of them up directly.
 
tell us more about the door manufacturer ma by you can foil a few sales for them as they sound like crooks.and help someone out.
 
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