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To David Buckwalter, totally agree with your advice to use a proper

crimping tool - I was remiss in not mentioning that in the earlier

post. Unfortunately, I took it for granted that such things are just

known (that's an OOPS!). The proper crimping tools are not the types

available from the auto parts store - those are fine for smashing a

terminal, but are bad for crimping a reliable connection. Generally,

the type of tools needed are those that have either changeable or

multiple dies sized for the terminal and wire size being crimped.

The most common, and easiest to use, also control the amount of

squeeze you can put on a crimp as too much muscle is just as bad as too little. Don't settle for anything less if you are crimping.



By the way, if you're soldering your connections, you sure better

be using "Tefzel" insulated wire (or at least, Teflon) because to

get things hot enough to make a good solder joint, you'll destroy

other kinds of insulation - like any of the PVC's, etc. Most all

of the older or auto type wire has the wrong kind of insulation

for aircraft use. Tefzel meets Mil Spec MIL-W-22759/16 for stranded

unshielded wire and is rated for 150 C max. This stuff feels "waxy"

similar to Teflon but it has a much higher resistance to cold-flow

and cut-through if, for example, it's rested on or pulled around a

sharp edge like a bracket or sheet metal corner.



Gerald Cerchio asked about pro's 'n con's of flying in prime and also

about Imron. If you can be absolutely sure that whoever does the

final prep for painting (either you or the paint shop) gets every

trace of oil, exhaust residue, bug guts and etc. off the prime, then

it's no big deal. However, I've seen the results on a friend's plane

where the painter was less than thorough in cleaning and some of

the paint, in spots, didn't stick well enough to survive being rubbed

out - some large patches came off on the bottom of the fuselage. You

just have to be very finicky about the final cleaning, or paint first.

Since you seem to be in the San Francisco area, check out the Calif.

regulations about Imron if you're going to do the painting yourself.

Imron is considered (for very good reason) very toxic in it's un-

cured form - if you are planning to paint your plane yourself, don't

use it. The shops that shoot it have to have some pretty sophisticated

equipment to handle the toxicity. You could end up with severe, and

permanent nerve damage - the proud owner of a beautiful, shiny air-

plane which you will be too screwed up to fly! Further, I was told by

the folks where I bought my paint that Imron, once cured, doesn't

touch-up well because Imron cures by what's known as cross-linking

within the curing layer and won't link to a new application once

cured. A touch-up will stick pretty well mechanically, but doesn't

really become one with previously cured surface. The paint folks

recommended Delthane catalyzed acrylic, which comes out nearly as

"wet look" as Imron, with none of the drawbacks. I used it, I've had

to do some minor touch-up and I like it.



Bob Belshe brought up a question about the Nav Aid autopilot tracking

a KLX135 GPS. As I noted in my last post, they seem to get along OK

but often settle down tracking parallel to the desired course with a

1 (or more) mile offset. Appparently the Nav Aid requires a minimum

amount of error signal to lock on the course. I'm not sure, but I

think it's because the error signal vs offset is linear and may

account for the insensitivity around zero error (offset). This is the

reason you need to crank in some a/p trim to fly the course center

line - that actually moves your desired track a ways left or right

while the Nav Aid is still happily flying with the original offset.

I'm not too comfortable with this so I'm building a error signal

amplifier with selectable gain and transfer function (gain rate curve)

as an experiment and will report on howgozit if it works out. May be

a while as I'm getting ready to retire after 30 years at the "Bomber

Factory" (or as some wags have put it, "B-1's are us") plus moving

out of Lala Land. Not sure where we're going to land but it's gotta

be outa California and in the Northwest somewhere. My wife likes

the Corvallis area of Oregon - anybody up there in on this forum?

What's the airport and flying weather situation up in that part of

the country?



Cheers,



Dan Schaefer





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