>
    > 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

Ken,
My batteries will be two 17 AH powersonic batteries, right now I'm
planning on putting them right in the stock location. One other mod that
I made to the plane was to use .020 skins on the elevators, and extruded
trailing edges, like on some of the newer RVs. Consequently, the
elevators have  one more inch of cord. So they weigh a slight bit more
than the stock .016 elevators. I'll let everyone know what the weight
and balancd turns out to be like when I get to that point.

Brian Trubee


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