We are currently working on my door handle assembly and am hoping for a bit of help. The bracket in the door that the handle spline sits in, is it supposed to have a hole in it? The top one is the NOS bracket I found (PN 0511106-30), and below is my existing one which was quite worn. Has the old one just been worn through, or is my new part slightly different?
When the spline is installed with the new bracket, because there in no longer a hole, it sits tight in the dimple and that makes it quite hard to turn.
Door Handle Assembly
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Re: Door Handle Assembly
First, welcome to the C-170 forum!
The bracket on my '52 door has the hole rather than a dimple.
By the part number you gave (0511106-30) I assume you have either a '48 C-170 or a C-170A. On the 170B the part number changed to 0511106-137 (fig.33-23) but the illustration looks identical to the earlier models as shown below. C-172's through 1959 had p/n 0511465-1 and the illustration of this part is slightly different. It could be my imagination but it looks like a dimple to me. In 1960 the 172 went back to the part number used on the 170B, p/n 0511106-137, but the illustration in fig. 42A-24 of the C-172 IPC matches the one of earlier 172's with the dimple. Here's one from a 1961 C-172 that has the dimple.
Do you think it’s possible that your NOS bracket is mislabeled? The door handle shafts have three different part numbers; one for the '48 170, one for the 170A and 170B, and one for the early 172's. It could be that the bracket with the dimple is designed to go with a shorter door handle shaft.
It seems to me that the hole wears because of the side load placed on it each time the door handle is rotated. If you don't want to drill out the dimple you might consider spacing the part out from the inner door frame to eliminate the interference fit. Maybe a dab of grease in the dimple would also help. Pressing a bronze bushing at that location might be something to consider ... or you could let your great grandson worry about it 70 years from now when it is worn out again.
The bracket on my '52 door has the hole rather than a dimple.
By the part number you gave (0511106-30) I assume you have either a '48 C-170 or a C-170A. On the 170B the part number changed to 0511106-137 (fig.33-23) but the illustration looks identical to the earlier models as shown below. C-172's through 1959 had p/n 0511465-1 and the illustration of this part is slightly different. It could be my imagination but it looks like a dimple to me. In 1960 the 172 went back to the part number used on the 170B, p/n 0511106-137, but the illustration in fig. 42A-24 of the C-172 IPC matches the one of earlier 172's with the dimple. Here's one from a 1961 C-172 that has the dimple.
Do you think it’s possible that your NOS bracket is mislabeled? The door handle shafts have three different part numbers; one for the '48 170, one for the 170A and 170B, and one for the early 172's. It could be that the bracket with the dimple is designed to go with a shorter door handle shaft.
It seems to me that the hole wears because of the side load placed on it each time the door handle is rotated. If you don't want to drill out the dimple you might consider spacing the part out from the inner door frame to eliminate the interference fit. Maybe a dab of grease in the dimple would also help. Pressing a bronze bushing at that location might be something to consider ... or you could let your great grandson worry about it 70 years from now when it is worn out again.
Gary
Re: Door Handle Assembly
Correct, my aircraft is a '51 170A. I think I'll try drilling out the dimple, as that's how it was originally. Thanks for your help Gary!