The International Cessna^® 170 Association

Hello fellow 170 owners and drivers....
Just joined the family when I picked up my '52 B model last week!! So now until I sell my '50 140A, I sort of have a fleet! Though not what I planned...
Now got a couple of issues I'm seeking help on.
#1; door close catches are severely worn. Functioning, but in dire need of replacement! Cessna part #0411552. Have same part on my 140. Been web surfing and that part number results in some ridiculously high priced returns!
#2; the door hold open catch. This airplane came with some sort of after market setup where a pin is attached to wing bracket, and the door has a spring loaded, nylon, spreading receptacle attached. Haven't found any reference anywhere to this mod. One of the nylon receptacles is broken, so returning catch to original may be necessary unless someone can point me to these parts.
#3; Door hinge sag. Is it realistic to fix door hinge play with slightly larger hinge pins? Left door has some sag but looks like total hinge replacements would be a big job...
So any suggestions, alternatives, etc....would be greatly appreciated.
Gary

Gary,

#1 Most of us put up with the mouse trap Rub Goldberg Cessna latch design with worn parts, slightly less worn parts, and occasionally parts we manufacture ourselves. Some have replaced the whole affair with later 172 style latches but there is no clear path such as an STC to do this.

#2 The door hold open latch. Another Rub Goldberg with about a 100 different mods that do the same or slightly different thing but most basically have a pin that stabs a clip. Most folks today discusted with these remove them and replace the function with Door Stewards. http://www.aircraftspruce.com/catalog/a ... teward.php

#3 There usually is not a lot of meat on these hinges and if they are worn that a larger pin would tighten it up, well, it is probably time to rebuild the hinges by welding on new material. This technique has been discussed a few times at the forum. Basically you remove what is left of the barrel and braze on a new barrel. Barrels can and have been made from correct or at least close sized tube or tube manufactured by drilling out a AN-3 bolt. Careful mechanics do not have to remove the hinges from the door to accomplish this but the repaired hinge will need painting. Once repaired as I'm talking about you won't have any further trouble in your life time with the airplane.

A local parts supplier mention this week that McFarland might be trying to get an STC for new hinges ( have you heard that before ). New 172 hinge halves run at 700 each. Even if McFarland does produce new hinges for the 170 and 172, I'll guess that they will want to get a good piece of that action for themselves. As well it seems a few part suppliers look at Cessna's list price and offer the part at 1/2 that number thus way too much ends up costing, just too much.

Aryana wrote:AN3 bolts are cheap. I'd try and drill a bunch of them hollow before I gave up and bought a $700 hinge.

Spruce sells 3140 round tubing in almost every size imaginable. That and a TIG welder (localize the heat, do it on the door) and you can make them good as new.

No need to drill bolts.

1/8" tubing is available (Home De...part) which appears to be the diameter of the original tube welded to the flat steel plate in the manner of which Cessna made the part. Gentlemen, I doubt I have that skill but for those in the know which technique works best?

Years ago John Benham, co-founder of the Cessna 170 Assn, knew I wanted to find a way to get an opening rh window in my 172. Since John loved going to auctions, especially aviation part ones, he found me a couple of later model 172 doors (basically the same as 170 doors). To complete the project he sold me one of his STC's for putting the later Cessna roll/ratchet latches in my plane. They are FAR superior to the 120/140/170/172, et al latches most of us found on our planes. Not only do they close the door so there is no sudden opening at an unexpected time, but they pull the door in against the seal MUCH better than the original latches. Go look at any newer Cessna door latch mechanism and you will see what I am talking about. Now the clincher-----I don't know whether the association was able to obtain John D's STC or not. It may have gone away with his extended exhaust pipe STC. Bruce probably knows the status of the latch STC, but I highly recommend installing a set of those latches even if it requires getting approval from the feds.

c170b53 wrote:1/8" tubing is available (Home De...part) which appears to be the diameter of the original tube welded to the flat steel plate in the manner of which Cessna made the part. Gentlemen, I doubt I have that skill but for those in the know which technique works best?

I'd think the 4130 would be more 'aircrafty'.

The originals weren't tubes but the flat hinge rolled over and brazed.
If yours are cracked, I'd first try to re-flow the brazing and chase the hole with a drill bit.
If the tabs are broken off, the tube trick would work very well but you'd need a creative jig (fixture) to keep it straight.
Brazing would be fine, welded would be better or possibly overkill. would depend on what tools you had and what you were good with.

170C wrote:-I don't know whether the association was able to obtain John D's STC or not. It may have gone away with his extended exhaust pipe STC. Bruce probably knows the status of the latch STC, but I highly recommend installing a set of those latches even if it requires getting approval from the feds.

As far as I know his door latch STC went to never again available land.

Bruce Fenstermacher wrote:

170C wrote:-I don't know whether the association was able to obtain John D's STC or not. It may have gone away with his extended exhaust pipe STC. Bruce probably knows the status of the latch STC, but I highly recommend installing a set of those latches even if it requires getting approval from the feds.

As far as I know his door latch STC went to never again available land.

Del Lehmann at Mountain Airframe made this mod on my airplane during the rebuild, and can probably tell us how he plans on doing the approval.

Regarding door latches, getting ready to repair/remake some of the parts.
Does anyone know if the holes in the bracket that holds the striker piece pin, are the holes elongated by design, or are mine elongated through wear? As I suspect. Going to add material and redrill the holes to accept a new pin. Both my door latches have equal sloppiness, and elongated holes, so thought I'd ask assuming I'm not the first down this path!
Thanks,
Gary