Hi! John.
Re:- Your message about the MK l Cowl. Have you thought about a replacement
Cowl ?
I have one for sale at a cheap price , and one of your American colleagues
will be over here in about two weeks and will visit me , he has bought a
kit and may be able to get an additional cowl dispatched with it.? If you
are interested.
Regards
Bob Harrison Builder 337 G-PTAG e-mail ptag.dev@ukonline.co.uk
-----Original Message-----
From: JohnJMoran@aol.com [SMTP:JohnJMoran@aol.com]
Sent: 14 April 1999 13:51
Subject: Cowl Blemishes?
I am using the Mk 1 cowl which I have stored for the past 2 years in a
spare
bedroom where the temperature is fairly stable - a relatively benign
environment compared to what the cowl will eventually endure.
Now that I have begun working on the cowl, adding the NACA duct and access
doors, I noticed that there is some cracking of the gelcoat on the upper
cowl
in a couple of local areas, one about 4 inches in diameter, the other about
2
by 3. There are other areas which seem to be starting to crack and all the
defects seem to be near the front of the cowl in an area which will be
prominent on the finished aircraft. The cracks have a peculiar branching
structure so I believe they are due to shrinkage rather than something
dropped on the cowl. There are two scrapes, on the top corner where the
cowl
bends sharply toward the propeller opening, which have been crudely covered
with gelcoat. There were also several small gaps or air bubbles under the
gelcoat along the top edge of the opening for the radiators. The lower cowl
is fine, with no cracking, bubbles, or scrapes apparent.
I pressed on the bubbles with a thumbnail to break them and will fill with
flox and sand so this should be no problem. The scrapes should be easily
fixed with micro.
My question is what to do about the cracking of the gelcoat which seems to
be
due to shrinkage of the gelcoat itself or a layer just beneath it. Is this
a
problem others have seen? Will sanding and filling solve the problem
permanently? How does one prevent this from continuing/progressing,
eventually causing cracks in the finish paint?
John A044
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