Other than sticks and sheets, all wood components are laser cut. The
entire model is built using Elmer's Carpenter's
Glue. I began
construction with the fuselage.
The fuselage sides are assembled from three pieces that key together.
This was the only problem in the kit. The left side of the fuselage did
not fit one of the mating pieces.
There is only one way the parts can mate
together so this was clearly a manufacturing error. According to the
directions the left and right sides are different to create
The lower fuselage piece is identical for both sides, but the upper two
pieces differ from side to side (according to the directions). I tried
mixing and matching the pieces with no luck.
I contacted Sig who sent me
replacement parts. The new parts had the same problem. I called Sig
back and was transferred to voice mail and I never heard back from them. I
have no idea if they have corrected the error or not.
I ended up using two of the upper right sides which mated perfectly with the
lower pieces. It is actually the forward pieces that establish the right
thrust and these pieces fit fine. I did not have to modify anything and
the fuselage sides came out as intended. The left side pieces are simply wrong
and won't work as supplied.
The instructions and plans may be wrong as well because using two right sides
worked. The fuselage turned out straight with the proper amount of right
thrust. All the formers fit with no
modifications. Had I not received the new parts I would have had to cut
new sides from
balsa wood sheets.
I left out the 3/32" square balsa window framing pieces that are supposed to
be glued in place when the sides are built because they are small and fragile.
I figured they would get broken at some point during construction so I glued
them just prior to applying the finish.
Various doublers are added to the interior of the fuselage sides. This
completes the fuselage sides which are now joined with formers followed by the
upper and lower sheeting. It's fairly standard construction. Even
though the parts jig together it is possible to build a crooked fuselage.
Take your time getting everything aligned before gluing it all together.
I assumed the model was designed to balance properly with the intended 1/2A
engine which is far lighter than the PJS motor. Therefore I modified the
model to place the servos behind the wing rather than in the cabin.
servos mount through a hatch on the underside of the fuselage. The chosen
servo location leaves the entire cabin available for battery placement to aid in
balancing the model.
I installed pull-pull controls using Power Pro braided fishing line as
a weight-saving measure rather than installing NyRods indicated on the plan.
The cabin is huge by the way. You can fit anything you want in there
including a pilot. In fact, if you are inclined to you can add a lot of
interior detail. Keep in mind that this model is not intended to be a
scale masterpiece and doesn't even have ailerons. Keep the weight low and
you will be rewarded with a nice flying model.
The cowl was almost as bad as the cowl included with the Pitts except it is
one piece instead of three. It had 2 or 3 large bulges and was very thin
on one side. It obviously didn't get pulled over the mold properly.
fiberglassed the entire inside of the cowl to prevent it from cracking and
especially to reinforce the thin side.
From there I
block sanded off the bumps taking care not to sand through the
plastic. I then wet sanded the entire cowl reasonably smooth in
preparation for paint. A couple drops of dark red
Klass Kote epoxy paint were mixed with an ounce of yellow to get a fair
match to the Oracover Lite Cub Yellow used to cover the model.
This quantity of paint (approximately 2 ounces including catalyst) was plenty
for the painted items which include the cowl, wing
struts, wheel hubs, control horns, cabin interior and firewall. I did not use any primer
on the model.
The interior of the cabin and all wood parts that would be visible through
the windscreen and side windows were sprayed using an Aztec
Finish-sanding removed the over-spray from the outside of the fuselage.
Covering was applied two days after painting. The Oracover adhered well
where it overlapped onto the paint Heat from the iron did not affect the
paint at all.
Like the Herr Pitts, the Cub uses covering to attach the fairings to the
music wire landing gear. Hopefully this one holds up better than the gear
on the Pitts.
The tail group is simple and straight forward. I cut control horns for
the pull-pull system from thin
aircraft plywood. The tail wheel wire is inserted into the lower part
of the rudder. I have done this on many planes and have yet to have one
break loose. I glassed the lower portion of the rudder to reinforce it.
There isn't a lot of room on the rudder below the stabilizer so I cut a slot
flat hinge to slide over the control horn. That allowed me to mount
both the horn and a hinge near the bottom of the rudder. If I had not done
that, the next closest location for a hinge would have been above the stabilizer
which is too far away from the control horn to provide good support.
you use the control system setup shown on the plan you won't encounter this problem.
The wing is simple and can be completed quickly. It consists of two
outer panels glued to a center section. The center section is built first
and then blocked up so that one of the outer panels can be built. When the
first outer panel is complete, the process is repeated for the opposite panel.
The dihedral braces are different than anything I've ever seen.
Rather than having a single piece go through the center into the outer panels,
the design uses two braces that meet in the center.
There are braces on
the front and rear of both the top and bottom spars - eight in total. This
didn't present any difficulty and is strong enough, but I would still like a
single brace better. I haven't been able to figure out the advantage of
the two braces.
The outer panels have two 1/8" square balsa turbulator spars on top of
the wing near the leading edge. The trailing edge is 1" wide balsa
sheeting on the top and bottom which I prefer to a solid trailing edge that is
unsheeted. The supplied sheeting was badly bowed so I replaced it with
wood from my stock.
The root of the outer panels and the entire center section is sheeted as
well. Again, the wing has no ailerons, but they can be easily added.
Mike thinks the model should have them but I like three-channel models. I
would build the kit for myself just as I built this one —
I sanded the fuselage to match the leading edge of the wing center section
after the wing was mounted. This completed the basic assembly of the
model. If you wanted to skip the detail work you could go straight to
covering, install your equipment and fly.
The Oracover Lite is very easy to work with and went around the curved edges
of the model with no difficulty. It isn't as opaque as heavier
coverings, but the model looks nice nevertheless.
I went ahead with the non-functional stuff just because it was fun to do.
The dummy engines consist of several balsa rings that slide over a 1/8" square
post. It is easy to build and adds a lot of character to the model.
I sanded the exhaust pipe as round as I could considering it has a rectangular
cross section. I also rounded over the engine heads.
After the parts were glued together I brushed on a coat of polyester resin.
The cylinders were painted with Testor's Model Master black enamel that was lightened
and flattened using a small amount of flat white. I had lightened the paint for my
because black never looks right. For this model, pure black would be fine. The engine heads were painted with Model Master Chrome Silver.
After the paint was dry I mixed up some gray oil paint
and dry-brushed the cylinders. The dry-brushing did a little to add contrast, but
because I didn't spend a lot of time sealing the wood grain and sanding to a
grain-free base, the effect was somewhat diminished. Nevertheless, I like
how it came out and feel it was worth the amount of effort I put into it.
Note that the enamels used are not fuel proof which wasn't a consideration
for this model. If you use hobby enamels, but use a glow engine, be sure
to spray a couple coats of clear fuel proof paint.
The completed engines were glued to the cowl using black silicone adhesive.
The wing struts are non-functional and simply plug in. They consist of
3/32" x 1/4" balsa struts with 1/16" music wire ends bent to an angle. The
sockets are pieces of inner NyRod that are sanded to have a flat on one side.
The sockets were CA'd to the fuselage and wing using medium CA after covering
was removed from the area. Be sure to iron down the covering securely
before cutting it and remove as little as possible.
The windscreen was temporarily taped in place and then marked using a Sharpie
fine point marker. Tamiya masking tape was used to mask off the area in
front of the line so that the anti-glare area could be painted. I brushed
on two coats of Tamiya semi-gloss black.
A large sheet
of plastic is supplied for the forward windshield and side windows. A
template for the windscreen is provided on the plan and is slightly over size
allowing for trimming to a good fit. The plastic is very thick for a model
During the fitting process, I was struggling to get the
windscreen to conform. I did not believe it would stay down for long once
it was glued in place, so I used thinner material instead (.010" thick butyrate
plastic available from K & S). This material is stiff enough to maintain
its shape while being thin enough to glue down in the first place.
Although the instructions state that the covering can be scuffed and have the
windscreen glued directly to it, I didn't trust that to work. I removed
the covering from the framing on the fuselage and painted it yellow and then
glued to the paint. If you take your time with the windscreen and follow
the directions you should have few problems. I cleaned up the lower windshield using
1/8" wide black pin-striping tape.
The side windows were glued to the covering because they are flat and are not
under the same type of tension as the windscreen.
As a finishing touch I used a Sharpie fine point permanent marker to
draw the cockpit door on the right side of the fuselage and the ailerons.
To ensure consistency, I cut a template from cardstock for the ailerons and put
a couple layers of tape inside the edge to raise the template so that the ink
wouldn't bleed underneath.
If you make a mistake, the lines can be wiped off easily using denatured