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Glad to!!
As with most great planes kits I've seen, the materials included
in the box are pretty good. The Tipo is a Fiberglas fuse, foam
core wing and stab type of plane. It must be built perfectly
straight and true if you want a serious pattern ship and in this
regard the kit is excellent.
Wing:
The foam cores in the kits I've seen (4 of them now) have all been
perfect, no twists, bows or warps. They come cut out of the blocks
and that's all. This leaves the builder to cut out all the recesses
and passages for things like spars, wheel wells, servos and linkages.
I made at set of router templates to do this work which provides
superior results in terms of finish but makes a huge mess with the
foam dust. It is best to run the front spar that supports the retract
plywood plate out about 4 inches further than the stock spar that comes
with the kit. This gives you a place to mount the aileron servos and
distributes the stress over the length of the wing. Do not leave these
spars out as the cutouts for the wheel wells will be very weak without
them and you will have problems with the landing gear tearing out of
the wing. The location of the landing gear center-line on the plans
is perfect, however you may want to move the wheel cutout inboard
1/4-1/2 " and the landing gear pivot point outboard 1/4-1/2" to
give the finished bird a little longer legs. This prevents dragging
the prop though the grass on takeoff and landing as the stock position
results in a very small ground clearance. Use epoxy in VERY small quantity
and glue in the retract mounting plate, spars, servo mounting plate and
trailing edge. I coat the wood and the use a rubber auto body squeegee
to remove all excess epoxy before assembling the parts. After this has
dried good, use a razor plane and a long straight sanding blocks to smooth
all the edges of the wooden parts flush with the foam. The worst part
here is sanding the plywood plate without changing the shape of the foam.
Just go slow and be patient. Sheeting is next, and I by this wood separately
from sig and only sig. They sell a contest grade, lightweight balsa that
can't be beat and it is worth the extra money. In addition to less weight,
each sheet is the same grain pattern and hardness so getting a smooth, even
finish is much easier. I never have found a great way to join these critters
edge to edge that I like, but for now I lay down some wax paper and thin zap
'em from the BACK side only. This keeps the surface that will be towards
the finish from having hard spots that will show through. After the "skins"
are glued together is the best time to sand them for finishing because
everything is nice and flat and you don't have to worry about damage to the
other side of the wing. I use one of those T-bars and get the wood to at
least 400 grit on the outside wing surface. Gluing the skins to the wing
is the most critical part of the whole building process. I bought a 1.5"
thick piece of marble to give me a flat surface to do this. Forget the
instructions that say you can do both wing panels at the same time, cause
you want them to be straight! I like epoxy for this job as well because
the contact cement type glues just never harden completely and after all the
work to get a straight wing, I don't want things to loosen up in the heat
of the sun. You have to go real easy on the epoxy or this process will add
a lot of weight. Again I use a slow setting epoxy and squeegee it onto the
wood so that it looks wet but not shiny. It helps in lining things up if
you draw some heavy black lines on the sides of the wing cores and the "saddles"
they were cut from before assembly. This gives you a reference to use to
position the cores in the saddles for bonding. After everything is lined up,
I put a couple of pieces of 3/4" particle board on top and weight the wing
panel down with 6 old car batteries. You want as much weight as you can get
to bond the wing skins to the foam. After the wing panel is good and dry,
sand the sheeting flush with the foam using a long sanding block and glue
the leading edge on with epoxy. I find that the easiest way to get nice
straight wing tip is to cut out a piece of 1/16" ply to the wing-tip outline
on the plan. Then I cut out the inside of the ply, leaving about 1/8" at the
very thinnest section on the tip of the wing and sandwich the ply between
two soft balsa blocks to give me the thickness of the wing at the tip. This
gives me a good reference line to glue the tips on straight and also provides
a reference in shaping the wing tip blocks on the outside and knowing how far
to go in hollowing them out on the inside. The line in the wing tip left
by the plywood in the middle is very helpful in getting the wing panels trued
up when joining the wing in the center. Because of the side mounted engine
you will probably need some weight in the L.H. tip. I use the same process to
build ailerons and elevators and if you cut out the notches in the ply before
you sandwich the balsa, VIOLA!! no hinge slotting!! Speaking of hinges, I use
dubro/klett style hinges. I think a lot of small ones work better than a few
large ones, 5 on each aileron, 3 on each elevator. A finished Tipo takes a
little more than 1/8" throw up and down on the ailerons and about 3/8" up and
down on the elevator, so go real easy on beveling the front edges of the control
surfaces. The 45 degrees on the plan is way too much.
Fuse:
Not too much to say here as the glass is most of it, but there are a couple
of gotchas. First off, the template to cut out the stab is useless. The hole
is too big and the result is down elevator trim or a whole lota' nose weight
to correct the problem. Use an incidence measurement or meter and set the
stab at zero to the thrust line that is molded into the glass. The instructions
for mounting the firewall are good, the only trouble with this is getting the
edge of the plywood firewall to mate nicely with the inside contour of the
fuse in the nose section of the plane. Probably unecessary, but for me this
amounts to roughing out the contour and then using a piece of carbon paper
on the inside of the fuselage, carbon side towards the wood, and tapping the
firewall into position to mark the high spots, removing the firewall, sanding
off the black marks, and repeating this until I have a good fit.
Finish:
I like to Fiberglas with 3/4 oz glass, polyester resin and then paint. This
is not easy, odor-free, or clean, but the end result is totally fuelproof and
never sags, shrinks, bubbles, ect. Polyester resin seems to harden the best
and it is important to have a hard surface to sand against after applying the
primer other wise it is too easy to sand through the glass cloth. Use the
resin very sparingly or it will add a lot of weight! Do not use cyano glues
to hinge the controls as they totally dissolve the foam core on the inside of
wing/stab! Again slow cure epoxy gives you plenty of time to get things
lined up and does a superior job. I don't "pin" hinges because I don't like
to hinge until after everything is painted. Melt a little Vaseline and let
it wick into the hinge joint before assembly and it will keep the epoxy from
doing the same. Silicone RTV adhesives work real well for holding things
like servo rails, fuel tanks, etc. in place inside the fuse.
Flying:
These planes fly extremely fast, it would probably be best to be just plain
bored with something like an aeromaster if this is your first pattern plane.
If not, get someone to help. Control throws will depend on things like
how tight the air gaps are ect. ect., but in general the plane takes little
aileron, little more elevator, and all the rudder you can get. The section
on trimming in flight has been reprinted in a lot of places and it is well
worth the effort to go through the whole process step by step.
Have fun!!
ron
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