Priming Torque Tubes & Push Rods

I've been putting off the priming of my torque tubes because I didn't have a great method in my mind for getting good coverage. On the RV10, the tubes are over 7.5 ft long each, so access is not easy.

The most frequent suggestion I've seen was to spray "a bunch" of primer inside the tube and swirl it around. I didn't feel comfortable that the rattle can had enough juice to go the length of the tube, so my best solution at the time was to buy Variprime and use it for the swirl. My thinking was that more liquid = better (compared to a rattle can). Problem was that the quart size of Variprime was going to cost over $120 with the converter. That stuff is liquid gold!

As I was at the auto paint store telling the guy what I was trying to do, he suggested an extension for the rattle can with a 360 deg nozzle on the end. Apparently its used in the autobody world for rust prevention around doors and fenders pretty frequently. The extension reaches 4ft so that my aircraft tubes could be primed from each end - and the best part was the cost was only $35. Sold.

Not much to the technique, but be aware of how small the surface area is that's being painted. If you are slow with the retraction of the nozzle, the primer will run all over.

Hope this idea helps someone else and prevents as much head scratching time as I wasted.

[URL=http://s296.photobucket.com/user/senecaprop/media/SprayExtensionNozzle_zpsqttehlhh.jpg.html][/URL]

Awwww!!! One week too late. Just did mine last week with the "spray a whole lot of 7220 in the tube and swirl it around" method!

That's a great idea, tho!!

FAA recommends boiled linseed oil. It is very easy to apply, drill a 1/8" hole in the pushrods and inject some into the tube. Slosh it around, drain and fill the hole with a tube rivet.

Really simple

Just follow Vans directions and swirl a bit if primer around in
Those tubes, done. For better paint distribution you can follow up
With a few burst of compressed air.
I have to admit the extension is a great idea but $35???

Linseed oil was the old standard, nothing wrong with it
But now you have to go out and buy linseed oil and what are you
Going to do with the rest of it?
Caution: Linnseed oil soaked rags can self ignite when left
In a pile and that is no OWT

Linseed oil

Somewhere on the FAA web site, they recommended boiled linseed oil for both aluminum and steel pushrods.

Interesting spray head. Do you have a name or manufacturer?
Could be very useful for applying corosionX or similar.
Thanks

This my 2nd post. Probably doing everything wrong. I am an rv8 driver, in Hilltop Lakes Tx. 0te4. I would like to purchase a QT technologies headset.They are not taking orders until they catch up some. Maybe someone has a used one that is excess. Thanks. 936 855 9013.

MODERATOR

Moderator, I think the above post would be better placed in "wanted/for sale".

Carroll, welcome to VAF!

Nozzle kit part number

Gisnar said:

Interesting spray head. Do you have a name or manufacturer?

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Transtar Part # 4471 - Corrosion Protection Kit. Available at O'Reilly Auto, or Amazon. I got mine from an Auto Paint specialty store.

N427EF said:

Just follow Vans directions and swirl a bit of primer around in those tubes, done.
For better paint distribution you can follow up with a few burst of compressed air.
I have to admit the extension is a great idea but $35???

Click to expand...

With a 7.5ft tube and not being able to see, I wanted the extra assurance that I had primer covering everything in there. I still don't know for sure without doing a borescope inspection - but THAT would be crazy overkill . Just another solution.

The linseed oil is hard to beat. If you warm it up you can feel the tube and tell where it is inside. This is the way the steel tube fuse homebuilders treat their's.

Linseed Oil and Mineral Spirits

Charles in SC said:

The linseed oil is hard to beat. If you warm it up you can feel the tube and tell where it is inside. This is the way the steel tube fuse homebuilders treat their's.

Click to expand...

You can thin it down with mineral spirits, apply and then let it vent for a few days, it won't be as thick but you can be sure to cover everything.

I still have the better part of a gallon of linseed oil from 30 yrs ago. I use it on shovel (and other tool) handles, (let it soak and reapply), it is great for gun stocks on bare wood, polish briskly to warm and it soaks in. When hunting and scratched by limbs and such, just rub again and it will be restored to like new luster. My Dad did his old Browning A5 round knob this way in 1962 and still looks the same with decades of steady use. Maybe I should use it too.

BTW - I took a small length of copper tubing, plugged the end and made circumferential slits with a dremel. Then took some white paper and lined a 1.5 " PVC pipe with it and sprayed inside, removed the paper and inspected to ensure it was covered. Less than $35, but not heirloom quality.

Hi All,
A year or so ago when I primed my pushrod tubes, I primed them and then wet riveted the end caps in place (using sikaflex pro), as I normally do when there are different types of aluminium interfacing one another. The only issue is this time that they are a tube, which means that I have completely sealed them off to atmospheric air. This is great from a corrosion perspective, however what I was thinking about is the effect of altitude fluctuations on a sealed tube. Looking at my stainless water bottle, it's a little beat up from altitude changes on commercial flights (the bottom is bowed outward). The question is, should I be drilling vent holes in the tubes (near the end of course), or is this a non issue?
Cheers,
Tom
RV-7.