removing trip jack screw

[robbie]

can you remove the jackscrew with out cutting the fabric??

[Robert Lees]

Re: removing trip jack screw

No, unfortunately, unless you have a big access panel. (I assume you mean the trim screw).

But you could access it from underneath the elevator, where any repairs are not obvious.

Rob

[Hank Jarrett]

Re: removing trip jack screw

Repairs to the elevator lower cover are straight forward but remember that the lower surface of a tail surface is the low pressure side in cruise (like the top of the wing). Notice there are no snap in covers on the top side of the wing? It's the low pressure side. Add to that the elevator deflects as a flap and the pressure on the bottom goes from positive (in a dive) to very negative when the elevator is up. Treat the repair like you would on the TOP of the wing. Elevators are a very bad place to use the round covers used on wing bottoms and fuselages. You see them all the time, but they are a BAD idea.
Hank

[flyguy]

Re: removing trip jack screw

Just whack a hole in the top fabric, fixit, replace fabric. It will function reliably several years without further service if you do it correctly. With modern fabric glues it is a piece of cake. Good practice.
DC
As someone said here, it is an airplane, not a work of art. Chuckle.

[Hank Jarrett]

Re: removing trip jack screw

Agree, cut the hole, fix the screw jack and repair the fabric as if it was a top wing skin repair (cut the hole on the bottom, it looks better). Leave a way to reach the lube hole (a small hole you can get a small tube through). I haven't used the removable cover ovewr my trim screw except for annuals since I owned the plane. I DO lube the screw! Works fine.
Hank

[robbie]

Re: removing trip jack screw

Thanks guys for your input, screw is freed up now but would like to put an oil hole on bottom side.
Thinking of a hole the size of a drain ,so in can get the nozzle in to oil the screw.The hard part is getting the hole in the right location. any ideas?

[Dick Smith]

Re: Location of lube oil hole on trim linkage assembly.

Robbie, are you aware of where the lube oil hole is? On top of the elevator..., close to the cable pulley). This picture points it out.
(Picture from Taylorcraft Gallery site...credit to Grant Bailey) http://gallery.taylorcraft.org/main.php?g2_itemId=866

Dick

[jdoran]

Re: removing trip jack screw

I put a seaplane grommet directly underneath the threads on the jackscrew. I can squirt oil directly thru the grommet - onto the threads by using the little plastic tube that comes with WD40 and the like.

The seaplane grommet is easliy installed. Use a pencil type soldering iron, melt a small round hole thru the fabric, and glue the grommet to the fabric with the "hood scoop" facing rearward.

[Dick Smith]

Re: removing trip jack screw

--------------------------------------------------------------------------------
Robbie, Sorry if I led you off in the wrong direction...I see you were talking about the lubing of the jackscrew threads rather than the trim shaft bushing....maybe the picture will help someone who hasn't been inside the elevator and observed how it works. I like John's idea using the seaplane grommet. Dick

[VictorBravo]

Re: removing trip jack screw

I put a seaplane grommet directly underneath the threads on the jackscrew. I can squirt oil directly thru the grommet - onto the threads by using the little plastic tube that comes with WD40 and the like.

Jackpot! Great advice, thanks. Makes perfect sense. Even a plain soldering iron hole with a piece of colored tape which can be removed to lube it.

[robbie]

Re: removing trip jack screw

I make a hole with a soldering iron and oiled the screw. works great,
My IA said to put some tape over the hole and we'll oil each annual
I like the idea of the sea plane drain hole cover.