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Anyone have any tips on getting the hinge pin back on. I don’t know if the hinge was distorted with riveting but I’m having a real hard time getting the ruddervators on to the stabilator. Is there an ideal way to bend the tip of the pin after installed? Thanks

Walter

Hi Walter

My two cents (worth a lot less).

When I tried to insert hinge pins and had issues, I used lubricant on the pin. Insert the pin as far as you can by hand, then chuck the end on in a hand held drill and while aligning the hinge as best you can, use a slow speed and work the pin in by spinning it with the hand held drill.

Your mileage may vary greatly.

Nice tapered point on the pin tip to help it "find" the next hole in line?

Wipe pin with WD-40 just before inserting.

and what Robbie said about a drill - with care.

Great, thank you. I tried the oil/lithium grease and it helped but it was a chore. Unfortunately I clamped a vice wrench a couple of inches from the hinge and used a plastic headed hammer to tap it in. This worked for a while but the pin buckled on me - twice! Didn’t think of the drill and tapering the tip so thanks very much. I had to take a break today due to frustration.
Always appreciate the help.

This has been said many times before and I always follow this procedure. I never rivet a single half of a hinge to an assembly without the other half of the hinge being pinned to it.

My experience is that the riveting process imparts a slight bending pressure to the single hinge. Not a lot, but enough to make alignment of the pin to the other hinge half very difficult at assembly time. The longer the hinge, the worse the misalignment is and the harder it is to get the hinge pin in. Also, always grind a soft point on the end to be inserted into the hinge halves and lubricate it.

I spray either WD40 or silicone onto a paper towel, and wipe the pin off. Besides lubrication, that cleans off the pin. Even if it doesn't seem dirty, there is wear going on and small particles being generated.
Never use a hammer. For the stubborn ones, I hold the bent end with pliers, and rotate it back and forth a little as I push it in. Much easier to break the static friction this way.

For the long cowl pin, I did take a spare pin and flatten/grind the end a little, to make a "reamer." I chucked that up in a drill and did a few passes. I wouldn't do that with ruddervators.

An interesting challenge for hinge pins are the Xenos Ailerons, which have a hinge that is 93 inches long, and as piano hinge length is max 6 ft means a long pin, and accurate alignment of both the hinge on the aileron and the hinge on the wing rear spar, as they can't be positioned and riveted in the assembled configuration. However, if one is very fortunate enough to find a skilled welder, the hinge pin can be joined so as to be effectively one piece. Otherwise to remove the inner section of the pin after assembly would require removal of a few hinge lugs. I used the white lithium grease but doesn't seem to be all that critical, although I would expect it to a preferable to WD40.

Serendipity showed me that motor oil is an excellent hinge pin lube.