Tight hinge pins

[Sonex1243]

Has anyone run into a tight hinge pin while installing a flap / aileron? I just finished a flap and during test fit, can get the hinge pin in about 2/3 of the way, then chuck it up in the cordless drill and insert as far as the clearance will allow. With the flap installed, there is no binding or squeaks as you move the flap.

I am curious as I had to use oversize 1/8 cherry max rivets on the surfaces due to aggressive deburring. Those cherry max rivets really lock down and wonder if that may be the cause of the tightness. I use the lowest recommended setting on the cherry gun as well.

[kmacht]

The slightest twist will make the hinge pins bind. If you have an extra pin you can make a reamer by filing down one end on the pin to a point (long ways so only half the pin tapers down) Try running that through the hinge using a high speed drill. It will open up the hinge to the exact size of the pin where it is binding. I also had to grease my pins to get them to go. Once installed though they worked perfectly.

Keith
#554

[mike.smith]

Just what Keith said. Same for me. If it's still binding you can *slightly* flatten the end of a piece of hinge pin and run it through. The flat end will be slightly larger than the I.D. of the hinge half and open things up a bit. But you don't need much, so don't over do it!

[Sonex1243]

Excellent idea's, thanks! Will give that a try after the ailerons are done so I can ream them all at once.

[kevinh]

The point about 'slightest' twist is a good one. I resorted to using a thick very flat/no twist piece of plywood on top of my workbench and that worked great.

[Sonex1243]

The point about 'slightest' twist is a good one. I resorted to using a thick very flat/no twist piece of plywood on top of my workbench and that worked great.

Kevin, dumb question, were you referring building flat on the work bench? I pilot drilled / built the controls flat on the (leveled) bench on the hinge side first so I could position and drill the hinges over a strip of .025 and .032 to set the .057. Then flipped them over and piloted the other side.

[SonexN76ET]

Here is an idea for you with the long hinges to keep them straight when fitting and drilling. Use both halves of the hinge with the hinge pin in place. That will keep the hinge more rigid and you will see if the hinge starts to pinch or bind as you are fitting and drilling and cleco'ing. Just fold the side you are not fitting out of the way. This unused side of the hinge would just be another piece of hinge you have not yet affixed to anything.

Enjoy your building project

Jake

[kevinh]

The point about 'slightest' twist is a good one. I resorted to using a thick very flat/no twist piece of plywood on top of my workbench and that worked great.

Kevin, dumb question, were you referring building flat on the work bench? I pilot drilled / built the controls flat on the (leveled) bench on the hinge side first so I could position and drill the hinges over a strip of .025 and .032 to set the .057. Then flipped them over and piloted the other side.

Yep.