Rear door problem

[Zac Weidner]

I have just put the rear door on, along with a striker plate that I produced, and the door seems to have "settled". The problem is that the thick steel plate on the door drags the striker plate as the door is shut(it also drags the frame without a striker plate) it shuts, but is tight and will scrape things all up after a short while. The aluminum panels seem to fit well and all the screws line up without flexing the aluminum, which tells me that the door frame has not been "tweaked" or bent. If I shut the door with a sort of "upward push", the problem is lessened, but still drags when opening. This also makes the door more difficult to open.

I would imagine that I could "live with" this problem but, first, I would hate to have a problem like this after a complete restore and second, it will wear out the striker plate over time. You can see in the picture where it is dragging. This picture was taken after only having had the door shut once.

Also, you can look at the striker plate and critique me on whether it looks like a correct striker. Anyone know what thickness they are supposed to be? Mine is .019" 304 stainless(same as what I used on my SS door channels.) I'm not sure if I can legally make this part, so I would like to know if this one can stay.

Thanks in advance



Zac Weidner

[jay heil]

well just a couple questions your problem is the door is tight in the rear direction as well as being tight in the low direction?? ok do you have a washer sandwiched in between the fusalage part of the hinge and the door part of the hinge with the door being on the top? and did you just do the door frame service bullitan? as far as the stricker plate it seems like .019 isnt very thick but its been a while since I took a good look at one I have one out in the shop I could measure somtime if you need it measured ,dont know why you couldnt use a home made one but Im not in charge of that hahahaha

[Steve Pierce]

Hang the engine. It will move the fuselage and might fix your problem. When we rebuilt my Dad's frame we made new doors and I made them tighter than the originals. :oops: Bad move. When we installed the engine we had a dragging rear door like you are experiencing. Live and learn. ;)

[Zac Weidner]

well just a couple questions your problem is the door is tight in the rear direction as well as being tight in the low direction?? ok do you have a washer sandwiched in between the fusalage part of the hinge and the door part of the hinge with the door being on the top? and did you just do the door frame service bullitan? as far as the stricker plate it seems like .019 isnt very thick but its been a while since I took a good look at one I have one out in the shop I could measure somtime if you need it measured ,dont know why you couldnt use a home made one but Im not in charge of that hahahaha

I do not have a washer between them like you said. Am I supposed to? It seems like hanging the engine and getting it off the sawhorse would help the problem if anything.

[jay heil]

I do not have a washer between them like you said. Am I supposed to? It seems like hanging the engine and getting it off the sawhorse would help the problem if anything--------- ya you need a washer I didnt look it up but wouldnt be suprised if they [2] dont have a part number since its kind of a bearing for the door to ride on

[Glen Geller]

Zac, did you have the engine off BEFORE you pulled the door, and the door was working correctly?
The washer is captured between two opposing leaves of the hinge, on the hinge pin acting as a bearing. This raises the moving part (the door) a tiny bit to provide proper clearance.
Once again, frugal yet clever engineering from Piper circa 1940's solves the problem of getting parts to fit together without needing close machine/manufacturing tolerances or super-skilled labor. Just try a few different thicknesses of washer until you are happy. Then hit it with a little LPS3 or 4 to keep the pin from rusting.

Added Jan 11: It occurs to me that one additional reason for the washer is to keep the two hinge parts from dragging against one another and scraping the paint away...

[Gilbert Pierce]

Just in case you don't know this, Piper doors are not interchangable. They have a serial number stamped on the hinge. You can't take a rear door off one aircraft and expect it to fit another.

[Zac Weidner]

I am pretty positive that our door was originally ours. The number stamped is 6424 and our serial number is 6412 but I think it is still original with our plane because it was the original paint and scheme on the door.

[Zac Weidner]

Zac, did you have the engine off BEFORE you pulled the door, and the door was working correctly?
The washer is captured between two opposing leaves of the hinge, on the hinge pin acting as a bearing. This raises the moving part (the door) a tiny bit to provide proper clearance.
Once again, frugal yet clever engineering from Piper circa 1940's solves the problem of getting parts to fit together without needing close machine/manufacturing tolerances or super-skilled labor. Just try a few different thicknesses of washer until you are happy. Then hit it with a little LPS3 or 4 to keep the pin from rusting.

When I took the door off, first I WD-40'd the button just to get it free enough to push, opened it and removed it without any thought about how the door worked. We bought the airplane as a basket case and any resistance I would have encountered would probably been thought of as rust. It was sitting on the gear, however. As long as there is supposed to be a washer in there, I will try that. It does make sense now that I think of it because I had to put two washers under the nut to get the cotter pin to hold with the correct bolt.