The problem with tightness of the Tufnol block at the base of the control
stick is that it is also seasonal. After time in damp weather (UK winter)
the Tufnol slowly absorbs water and expands. Dries out again and frees-up in
Summer.
I've found that silicone grease seems to kill this cycle, eventually.
However, care is needed with aerosol silicone grease as the carrier solvent
can also make the Tufnol expand.
Of course, you need to be extremely careful in letting silicone grease
anywhere near a composite a/c, especially before it is constructed, painted
or repaired!
Duncan Mcf.
----- Original Message -----
From: <rparigor@suffolk.lib.ny.us>
Subject: *** SPAM *** Re: Europa-List: New problem.... The Sticky Stick
>
> Hello Dan
>
> "Has anyone out there experienced stiffness in the left/right movement of
> their control stick?"
>
> Boy it sounds to me like you are in a good position to deform some body
> parts, both Biological and Europical!
>
> First off there is a good chance you or someone else will not walk off
> without some pretty sore fingers with blisters on them.
>
> Our XS Mono kit A-265 was purchased with an accelerated CPM. The roll was
> just a tad stiff when I got it. I thought it just on edge of usable. When
> it sat just bout a year and we were ready to bond in, it became stiffer
> beyond what was thought acceptable.
>
> What I believe happened is whoever built lubricated with some grease and
> it expanded the tufnal!
>
> I was able to beat with a sledge hammer the aft bushings out (again CPM
> was not bonded in place at this time) and use a flap wheel to enlarge a
> bit, then lapped a bit. You will not be able to do this since your CPM is
> bonded. You can probably lap the rear fit.
>
> I lapped the front bushings while it remained on the tube, but was pushed
> forward because the rear bushing was out. It needed more clearance both in
> fit of round tube in round tufnal, and equal needed more clearance in fore
> aft fit. I will describe what I used that worked well, downside is it is
> messy and takes a fair amount of time.
>
> Traditional lapping compounds are usual very hard. Once they embed
> themselves into something, they continue to cut, and can be very hard to
> get out once you are done. Thus in this instance you don't want to leave
> anything hard inside bushings as it will continue to cut forever.
>
> I used a lap sold by McMaster Carr www.mcmaster.com It is a yellow
> powder that you mix with cutting oil. I purchased a gallon of Pig Oil to
> use. Lard is good for cutting and tapping on most things, really good
> stuff to have around. Works good for sawing metals.
>
> The stuff begins as a lap, then turns into a polish, then complete stops
> cutting. It is guaranteed to be safe to use inside a engine! The stuff I
> used is yellow and I think it was meant for soft materials.
>
> I had the CPM out so was able to angle things and had the front joint
> outside of the CPM by a bit. Mess was manageable, and aft did not need
> much. You will need to make a dam, cut strategic access holes or something
> like that. You need to keep nice and wet with Pig oil and when it stops
> cutting add more. Gray slime is the aluminium being cut, keep it cutting.
> Tape and cover anything that may get touched, this is a mess you are about
> to make no matter how careful you are.
>
> This is a slow process, best just get things set up, then join over a few
> friends with draw of free flowing pints so you can get job done before you
> can think bout what you are really in for, for too long.
>
> Take a scrap of fiberglass and coat it with pig oil, then see what is
> needed to clean it, then bond it and fail it till you have it figured out.
> Palmolive green original dish-washing detergent is a good final cleaner,
> use the hottest water your hands can take. I was using pure Isopropal
> Alcohol as a quick wipe to keep major mess under control.
>
> Good Luck
> Sincerely
> Ron Parigoris
>
>
>
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