Mark, You could use a self etching wash primer like the PPG DP 701, it's a two equal part mix. By asking at the local jobber store (Auto Value here) you could find who is using it locally and get a pint. I think the smallest they sell is quart and you won't need a half gallon of the stuff. Swab the inside of the tube like you would a gun barrel, and spray the outside with enough to wet it. Same as if using zinc cromate. I use it all the time at our shop for repair and rebuild work and it works great.
Ed Larsen Ypsi, MI << Mark Langford wrote: > Some of you guys might know the answer to this, and since it's been quiet > I'll throw this out. My flap torque tube is a piece of .75" 4130 steel > tubing that extends from one end of the stub wing to the other, right > through the cockpit, where I have an RV flap motor attached to it by way of > a clamp-on bellcrank (see http://home.hiwaay.net/~langford/03060120.jpg ). > I got smart a while back and painted it along with some other stuff, but the > fit was so tight on the holes that there's no way it'll fit back in the same > holes, and enlarging them would be very tough. Is there some thin chemical > conversion coating that I can apply to the new bare one that bought that > will keep it from rusting, while not adding a bunch to the outside diameter? > I even thought about waxing it, but if it doesn't work I'll have to take the > wings off to try something else, which sounds painful. > > I suppose worst case is that I figure out a way to open up the holes, so I'm > open to suggestions on that too. I guess I could "booger" up the tube a > little with burrs on one end and run it through while somehow rotating it > with a huge drill and open it up, but that doen't sound very exact, or > appealing. It's such a nice fit right now... > > Thanks, > > Mark Langford, Huntsville, AL > N56ML "at" hiwaay.net > see KR2S project at http://home.hiwaay.net/~langford >>
