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Re: Inspection



Errm, hate to be picky, but the heatshield paint will only work that well in a vacuum. Paint conducts the heat pretty well - what NASA do is create one (black) that has a very high emissivity (radiates heat out well) and low absorptivity (in the infrared) - so that little is absorped during re-entry (and lift off).  It will improve things if most of the heat is being absorped by radiation, which might be the case (exhaust headers at say 300C, fairing at 25C, good cooling airflow between them etc.), however, the fairing will never get hot enough for the high emissivity properties (ie. being able to radiate the heat back out to 'deep space') will work.... so I am a bit doubtful that it is anywhere near as effective as foil/loft insulation type products.
It seems the main problem here is getting the heat shield to stay stuck down after it gets hot - the glue they use as stock is not up to it.  Try silicone RTV type glues (get them at a yacht chandlers or DIY centre).  This is what we use on spacecraft.

ttfn
Jonathan

>>> dan & ann curcio <curcio@xxxxxxxxxx> 10/08/99 07:08:39 >>>
You may want to try a different approach to the heat problem.  I would suggest trying a heat barrier like the auto racers use for the floors in their race cars to stop exhaust heat transfer to the interior.  There are two products of which I am aware.  There is an aluminized heat barrier that is made of the same material as header wrap but it comes in sheets and the aluminum stops any oil soaking which could lead to a fire.  The other product is a heat shield paint  which was developed by NASA for the heat tiles on the space shuttle.  It will actually insulate any surface to which it is applied and stop heat transfer by 50%.  Both of these products could be applied to the inside of the fairing instead wrapping the exhaust pipe thereby eliminating the damaging effect of pipe wraps to the header.  These products can be purchased through Racer Wholesale at 1 (800) 886-7223.  They also have a tech line at 1 (800) 397-7811.  The heat shield paint is part# RB-101 and is sold by the !
quart
for $24.99 and the aluminized heat barrier part# AUT-P100A sells for $29.99 for a 40" x 36" x 1/16" thick piece.  Hopefully one or both of these products can save your fairing.  I have not had any problems with my lower fairing yet but up here in Wisconsin we don't get a lot of really hot days.

Dan

David Arnett wrote:
....I also noticed the heat shield sticker on the lower right belly pan was peeling away and found a burnt hole in the spot where the exhaust collector welds are near.  The bodywork has not started to melt, so that's good.  I wanted to use some of that exhaust wrap insulated tape in the area, but was unable to locate the stuff in the time I had, so I went with an exhaust repair kit which contained fiberglass tape, resin, a metal sheet, and some way too springy bailing wire.   I thought that this repair kit could provide enough heat shielding in this critical area.... The drawback is that the wrap is ugly, and can collect moisture, which will shorten the exhaust's life.  I figured by using more "stick on" heat shielding material, that it would start coming off just like the original, and start burning again.

>
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