There are times, when using hinge material as joints and fasteners (for things like cowlings) that it is convenient to use an undersized pin to make things mate up more easily. Van suggest this in several; places, such as for the firewall cowl hinges. I find that generally, if you do a really good job of lining things up during the build, cowl hinge pins can be a bit of a pain to remove and replace for a hundred hours or so when they are still wearing in. There are numerous ways to fix this, including grinding a point, or a flat ?bit? and point on the end and spinning them in with a drill motor. The good news is that they will almost always eventually get easier. We used hinge material for the side cowl fasteners on our RV-3 because I like the clean lines you get with the hidden hinge, and by putting the hinge pin in from a hatch in the back, they are completely invisible. Unfortunately, they are still nice and tight, and need to be spun in the last foot or so and this means spinning a drill motor perilously close to our new paint job.
So this thread isn't about debating all of the various ways you can rig hinges - it is just to point at a source for smaller hinge material, if you choose to go that route.
David Howe, an RV and Rocket builder from California, suggested a great source for marginally smaller pin stock ? good old McMaster-Carr. I thought I?d pass this on to other interested builders ? just go to www.mcmaster.com and search for Tool Steel Tight-Tolerance Rod. They sell it in 3? lengths in fractional sizes below the stock .090? that comes in the hinge as standard ? I got several lengths each of .088?, ,085?, and .081?. The .085? size fit really nice right now ? I expect that it will eventually loosen up a bit, and we?ll go to the .088?, and if that loosens up, we?ll be back to the nominal. It?s pretty cheap BTW ? less than $3 per length.
Paul
So this thread isn't about debating all of the various ways you can rig hinges - it is just to point at a source for smaller hinge material, if you choose to go that route.
David Howe, an RV and Rocket builder from California, suggested a great source for marginally smaller pin stock ? good old McMaster-Carr. I thought I?d pass this on to other interested builders ? just go to www.mcmaster.com and search for Tool Steel Tight-Tolerance Rod. They sell it in 3? lengths in fractional sizes below the stock .090? that comes in the hinge as standard ? I got several lengths each of .088?, ,085?, and .081?. The .085? size fit really nice right now ? I expect that it will eventually loosen up a bit, and we?ll go to the .088?, and if that loosens up, we?ll be back to the nominal. It?s pretty cheap BTW ? less than $3 per length.
Paul