Since no one offered use of their paint booth
last October, I was forced to wait until spring. So, here we are,
April 2015 and already plenty of days warm enough to paint,
however.....I ran into trouble last fall. I shot the rudders with
Polybrush right over the old dope finish and then Insignia white
color base coat and proceeded to mask the accent stripes. After
making a masking error requiring tape removal, I found the base coat
peeled off with the tape right down to the old dope finish. No point
in going further. Ripped off all the covering on both rudders and
set about prep'ing the frames for recovering. This pretty much shot
the idea of completing the painting last fall. I found that the left
rudder had actually sustained some damage once I had the covering
removed so I fixed that and beefed up the aluminum ribs which are
definitely the weak link in the frame structure. Here's a shot of
the rudder frame leading edge rib before.
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I cut out a piece of ½ inch foam from the
damaged wing rib to fit inside the aluminum rudder rib. I glued it
in place using Gorilla glue which is supposed to work well on this
type of foam. The stiffening effect on the rib was amazing. If I
build another ER, I'd use this on all the aluminum ribs in the
rudders which would also allow one to rib stitch rather than rely on
the dicey fabric to aluminum bond using fabric cement (without the
foam insert, the rib would just collapse as you tightened the stitch
knot).
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I recalled covering these rudders back when I
first built this kit that they were very difficult to do without many
wrinkles so both these rudders were ugly anyway. I decided to try a
different method this time around and built a quick frame out of 1X2
fir and attached a piece of fabric to it using an office stapler.
I cleaned up the aluminum frame, coated it with
Polytak fabric cement and then place the wooden frame over the
rudder structure.
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A small slit for the rivnut to poke through
allowed the fabric to lay down nicely onto the rudder structure. I
then ran a very thin line of 50/50 cement/MEK around the entire
perimeter of the rudder, rubbed it in and let it dry (std process).
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I then simply cut around the perimeter leaving
enough fabric to do the wrap onto the aluminum structure and got an
almost wrinkle-free main area. The hard part was doing the snips and
cuts to get the fabric fitted around the ends, brackets and horn.
Repeated the frame process for the other side and ended up with no
wrinkles after doing the final shrinking at about 300 F. Wetted out
the glue on the ribs to attach fabric then applied Poly-Brush (coat
#1 brushed on, coat #2 & #3 sprayed on). Same pin hole bubble
issue. Just have to re-brush back over what you've just applied as
you go to knock down the bubbles before the P-Brush tacks up. What
you don't get will be ironed out at 225F prior to spraying.
Here are the rudders after completing all the
gluing, smoothing with the iron and general detailing finishing with
the first brush-on coat of Poly-Brush.
Here they are after the final sprayed on coat
of Poly-Brush......
OK, on to painting. I've poly-brushed the
rudders and shot the base coat of white. Two coats was sufficient.
One thing I've found in getting an even coat aside from being very
smooth and even on your gun passes (you need to always be aware of
how far the nozzle is from the surface, what angle the spray fan is
relative to your gun pass direction and how fast you move the gun
along the surface). It's a tough job and was hard for me to do. I
would finish a panel and then go back and look for uneveness. I
would then spot spray the light areas until the whole thing looked
relatively even. I tried to put on just enough color on the first
coat so that the second coat was the final one. In the photo below,
notice the different color masking paper on the leading edge at mid
span. That stuff is the paper you use when you paint a room in your
house which I suspected when I experienced bleed through. I'm not sure if it's the paper because I went
to an auto paint supply shop and got their masking paper and had a
little better luck but still saw it bleed through a little. I think
the take away here is to DOUBLE LAYER THE MASKING PAPER OR USE A WIDE
BORDER OF TAPE next to the paint line. Also helps if your technique
is good enough to allow very little paint overlap onto the masking
paper. As you can see in this photo, I don't do a very good job of keeping paint off the masking paper. I was fixing a screw up here where I forgot to take the accent stripes all the way to the root on the lower panels. I am leaving a gap at the root on the upper panels where I will strip the paint back and glue on a fabric closure with a zipper after I'm finished. Darrel did this on his and it works really slick.
In this next photo, I've removed a piece from
the other wing panel where I had used it right in the area I was
painting. You can see what happened.....bleed through! So go find
your local supplier for automotive painting and get your paper from
them but I'd still test it first before you commit to use it to mask
an entire wing....it took me a couple hours to finish one panel and
that was after I got the hang of it.
I used Reducer on a Q-tip in an attempt to
mellow it out a bit with limited success. I went over the area with
red but could not make it go away.
Here are some shots of the masking involved in
creating a simple design scheme similar to the lines on the glider
Brian Porter flew in the 1976 National meet.
The blue tape in that shot is vinyl tape used
in automotive trim masking. You can form it somewhat around curves.
I could not do a real tight curve successfully and ended up cutting
the curves for the rudders which were much smaller radii compared to
the wing panel curves.
Back in the converted RV shed with the
drop-down lights for painting.
Masking the rudders.
The finished rudders ready for painting.
This next photo shows my attempt at getting an
even first coat of red on the rudders. I always shoot the edges
first since this is where the risk of generating drips is greatest.
Making a couple light passes worked best followed with filling in the
rest of the surface.
Here is a shot of the final accent stripe of
gold as I am removing the masking tape around the curve. Gives you
an idea of the cutting and fitting I had to do in order to obtain a
nice tight curve around the bend.
One thing I did which really helped get the
last little bit of paint out of my cans was to use a metal shears and
cut through the lip gutter then pour out the last bit of paint and
rinse with a little Reducer.
I got a couple small
areas where the color pulled off the Poly-Brush surface with the
masking tape. Likely some contaminate I neglected to get off prior
to painting. I'll need to touch it up with a fine tip
brush later.
Here are more shots of the rudder masking for
both the red and gold accent stripes. Lots of time masking and
re-masking to do even simple paint schemes like I'm attempting here.
As a side note, it was 58F and raining when I shot these. I saw no problem with the paint nor did I note any difference in spraying under these cool conditions.
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