Hans-Peter,
I have fitted a nav lights in the forward wing tips of my XS.
I began by determining how long and deep the recess needed to be to fit the nav
lights. I then scribed a line in the surface of the wing tip where I would be
cutting out the section. I then waxed and applied mold release to the area.
I then did a 'splash' layup with 4 layers of bid, to be used to create a mold
for vacuume forming the clear lens. In this way I would be absolutely sure the
lens would conform to the original wing tip shape. The scribed line shows up in
the layup mold, and are used later to trim the clear lense.
I then cut the new mold parallel to the scribe lines, about 1/4" away from the
cut line that parallels the wing chord line, and about a 1/2" away from the cut
line that runs spanwise. The chord edge becomes "up" and the spanwise edge
becomes an open 'side' of the mold.
I then mounted 'legs' to the mold using bondo (on the outside of the mold) - the
legs being flat pieces wood, such that one piece created an 'end' to the open
section of the mold, and the tops of the flat piece legs being even with the top
of the mold. So now you have a sloping cavity that is borded on one side and
sits flat, the bottom about 2" off the table.
In the 1/2" space between the spanwise scribe mark and the board end, drill and
bond into place a 1/4" barb hose fitting. This will be used to draw the
vacuume.
I made a 1/2" angle iron frame, the inside dimensions between the angle iron
slightly larger than the width and length of the wooden legs. Using small
spring clamps I held in place a piece of 1/8" thick plexiglass cut to fit inside
the frame. I placed the frame/plexi/clamps into the oven on wood blocks and
baked it at 340 degrees F. (It smokes at this temp) The plastic becomes
filmy/fluid.
I removed the assembly from the oven, quickly laying it down on top of the board
end legs (the legs and the top edge of the mold all being flush in relative
height, and the angle iron frame with the angle legs pointing upward) and drew
a
vacuume on the mold using the family canister vacuum cleaner with the 1/4"
suction hose duck taped to the canister hose. (This is truly high tech) I had
planned for adjustable openings to control the draw, but turns out, you can just
go full tilt. The fluid plastic drapes onto the mold edges, and creates the
seal allowing the pulling of the center of the plastic into the mold. Took
three tries on my first one, two on my second.
I made aluminum pieces with formed tabs to fill the leading edge hole that was
created by cutting out the wing tips. I'm not sure I'd do it this way again,
(t'was time consuming) but the challenge is getting a square inside corner that
radiuses outward in two directions, and also provides a mounting surfaces for
both the nav light and the new lense.
I've attached a picture of the splash mold being made and the finished mold with
the legs. Feel free to drop me a line if you'd like more info.
Cleve Lee
A198 Mono XS Jabiru 3300
On Tue, 21 Jan 2003, "Hans - Peter Reusser" wrote:
>
> I am working on my XS-wings and am considering to mount nav and strobe lts.
> Now I have a few questions and hope somebody can give me some hints:
>
> - Did anybody figure out what the performance penalty is for fitting,
e.g.
> a Whelen A 600 or similar unit to the wingtip?
> - I would prefer to mount the coloured nav ligth as well as the strobe
> light to the leading tip corner of the wing under a common acrylic
> wingtip
> lense.(like they do it on the airliners) Would there be a heat problem from
> the lights under the lenses?
> - Does anybody have knowledge of instructions on how to form acrylic
> glas
to
> a given shape?
> - Has anybody fitted a landing light into the wing leading edge of an
XS
> wing under an acrylic glas cover? if yes could you give me some advice
how
> you've done it?
> - And now one final question: If I cut holes into the wing ribs for
> flexible
> tubes to run throug for the nav light wires, do these holes need some
> strenghtening lay ups?
>
> Many thanks for your help
> Hans-Peter Kit # 498
>
>
> *****************************************************************
>
> Hans-Peter und Christa Reusser Tel: +41 (33) 654 00 24
> Spiezbergstr. 13 Fax: +41 (33) 654 30 21
>
> *****************************************************************
>
>
> The Europa Club website is at <<a
href="http://mail.cswebmail.com/jump/http://www.europaclub.org.uk>">http://www.europaclub.org.uk>;
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