>
    > Brian,
    > Your work looks excellent. Within the next year I am going to
    > have to build a complete cowl from scratch and as yet know nothing
    > about glass work, mold making, weave to use, layers to use, etc. So
    > any small tidbits of info on what you did would help. I save
    > everything pertaining to glass layups but, so far, most want to show
    > off their excellent work but not reveal how they did it. Also, I
    > would like to know the general dimensions and weight of the
   completed
    > cowl if possible.
    > Thank you,
    > Randy
    >
    >
    > Thank you. I'm art work until monday, so I'll get you the weight
   of the
    > cowl at that time. The cowl is 44 inches from firewall to spinner. I
    > wrapped the engine in a couple of rolls of saran wrap, then
   rolled some
    > screen material over that to hold the two part foam that I slathered
    > over the engine. Here's a tip- bulk out the whole thing by putting
    > newspapers or hunks of styrofoam around the engine to get it near
   the
    > size of what you want the plug to be.(The foam isn't too cheap, and
    > there's no advantage to useing lots of it.) Then wrap the whole
   thing in
    > saran wrap & screen. after you get the foam slathered on and it
   expands
    > and hardens(you'll have to do it in small batches and keep
   filling until
    > you get enough size) then you can sculpt it down to close to
   where you
    > want it.
    >
    > I used a surfoam tool and 50 grit sandpaper glued to a piece
    > of 1/4" plywood. I then got a bucket of drywall compound and
   coated the
    > whole thing and then sanded it down to a very smooth finish.
   You'll have
    > to sand and add drywall compound a few times. You want a nice smooth
    > contour. I checked the contour from side to side with a template cut
    > from cardboard. I then painted two or three coats of ordinary latex
    > paint onto the the plug and then waxed it. I had a problem with the
    > resin making some of the foam underneath shrink a bit, so I had
   to fill
    > in with some more dry wall compound. In retrospect, I think that I
    > shouild have had a much thicker coat of drywall compound, it remains
    > stable when in contact with the polyester resin., and It's way
   cheaper
    > than the expanding foam. If you have layer of drywall compound
   that was
    > 1/2 inch thick, I think that you would avoid any stability problems.
    >
    > When you have the plug the way you want it, wax it and lay up
   from 4-5
    > layers of plain weave 5.8 oz cloth. Your probably better off
   laying no
    > more than two layers at a time. I had no problem laying whole sheets
    > over the top part of the cowl, but found it much easier to use
   smaller
    > pieces around 1 foot square. After you have all your layups done,
   you
    > can fill low spots with resin mixed with microballons, sand and
   repeat
    > until you have the finish that you can paint. I used a 2 x4
   kerfed so
    > it would bend and clamped it on the side of the cowl to use as a
   guide
    > to cut the cowl off. It made nice straight cuts using a die grinder
    > with a 3" wheel. Lots of gentle, loving prying was required to
   remove
    > the cowl from the plug, with a lot of the plug remaining stuck to
   the
    > cowl. I borrowed my neighbor's pressure washer and cleaned that
   crap off.
    >
    > One tip- I have a flange riveted to my firewall that the cowl
   fastens to
    > with piano hinges. Before you cut off your cowl. drill a couple of
    > holes though the cowl into whatever you are mounting it to so you
   have
    > reference points, and can cleco the cowl to the airplane. Also,
   drill
    > and cleco a few pieces of aluminum sheet between the top and bottom
    > halves of the cowl to use as a reference.
    >
    > The forward bulkhead was cut out of 1/2" hexcell and bonded in.
    >
    > I'm sure that this whole procedure raises a lot of questions,
   feel free
    > to contact me if you think I can be of assistance.
    > bktrub@aol.com

   Brian,
   My prop flange is 43 inches from the firewall; I'll be interested in
   seeing how your weight&balance works out.  Where is your battery
   located?

   Ken Powell
   Bryant, Arkansas
   501-847-4721
   C150 / RV-4 under construction



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