Side window install

As our Aztec was down due to a leaky prop seal, we began the install of our
new 1/4" side windows. After removing the plastic surround trim and mapping
the screws, because they were several different sizes and lengths, we then
had to remove the window retainers. The retainers are basically some fancy
L shaped aluminum pieces that when installed hold outward pressure on the
windows forcing them into the adhesive tape that Piper so liberally applied
when the plane was built.

Our old windows were a thermo pane design consisting of a 1/8" outer window,
then a space created by the retaining bracket, and a thinner inner pane of
Plexiglas finishing up the sandwich. I'm sure that Piper had good
intentions, but this design leaves no ability for cleaning the insides of
either the two panes. It also allows the panes to rub together and chafe,
creating a lot of crazing.

So after removing the window retainers, it was time to do some serious
cleaning. The adhesive is a fabric tape coated with 1/4" of a black tar
like substance that is nearly impenetrable with any kind of solvent. MEK
seemed to work a little, but most of the time it just made it smear. The
best method that we found was after scraping as much off with plastic putty
knives, we would create a small ball of the goo and then use it to dab onto
the window sill then briskly remove it so more black goo stuck to what you
held in your hand. Kind of like dabbing chewing gum off your kids face
after they blow a bubble. A second round of MEK cleaned things up very
nicely.

Most of the LP Aero windows fit right in, but the pilot's side window and
the cabin door window required roughly 1/4" be removed from two sides. A
fine toothed band saw blade worked well followed by finishing and beveling
with a belt sander with an 80 grit belt. LP was nice enough to notch out
the top of our passenger side center window due to the protruding rivets
along the top, but for some reason they forgot that the pilots side window
has the same rivets. Oh, well the bandsaw and the belt sander made quick
work of resolving that problem.

After dry fitting with the protective plastic still applied to the windows
we pealed the plastic off and then squeezed a nice thick bead of black
silicone to both the window frame and to the window itself. Being super
careful not to touch anything with the pre-gooed window, we slipped them
into position and then pressed them tight, forming a good seal letting the
excess silicone ooze out from around the edges. After mistakenly letting
the first two windows set overnight, we quickly learned that it is easier to
clean up the messy wet silicone immediately after installing rather than
letting it dry then cutting and scraping it off later. With fingertips
blistered from rubbing, lesson learned, not to be forgotten.

Reinstalling the retaining brackets was a no brainer. While the silicone is
still soft, fit into place, press against the window until the screw holes
line up, reinsert screws. No need to drill new holes for the thicker
windows, they simply took up the same thickness as the old thermo pane
design, but since Piper never installed 1/4" windows in the Aztec we
couldn't get away with the part 43 logbook sign off for simply "replacing
side windows". LP required a 337 for this install and notices about it were
plastered all over the packaging. Since we ordered them through our A&P -
Aztec owner friend, he filled this out and it was approved through the mail
and with a phone call as "previously installed under previous documentation
and approval in same make/model".

So with windows in and approved, now it's just a matter of refreshing the
condition of our 40 year old plastic trim. Plane Plastics demands roughly
$135 for each of the 5 pieces that surround the windows, so before spending
that kind of $$$ we decided to see what we could do with a fiberglass repair
kit and some spray paint. After searching the group posts and reading up on
what people were using to paint plastic and what SEM paint cost, I talked
with a couple A&Ps that work on many of the rental planes in the area.
Their paint of choice? Fleet Farm. (a local midwest farm and home supply
store) Good coverage, no pealing, no sticky residue and their Almond color
matches the old Cherokee off white, and the Sand pebble color matches the
old Cherokee tan color.

After sanding, prepping, patching, and reinforcing the screw holes with
fiberglass, a little sanding then cleaning with MEK, the first piece was
ready for the paint test. I must say that the cheap FF brand paint worked
as advertised. I gave it 3 light coats then let it dry overnight. Once
installed, the first piece looks as if it had just came out of the
factory... well almost, but a lot better than the hole $135 would have left
in my wallet.

Two more pieces ready to go in tonight, then just 2 more to go.

For those who have repeatedly contemplated how great their plane would look
with new glass but have had a fear of the costs, this is a project that you
really can take on yourself and do a nice job with. Total cost for us for
tinted 1/4" side windows will be less than $900. (note: we did not replace
the emergency exit center left window as it is a single piece design, rather
hard to replace, and was in excellent condition) In most cases, if your
side windows are an exact replacement, no A&P or 337 is required, just a
simple pilot sign off as part 43. The first thing that we noticed was how
the new glass made our paint job look even better. I can hardly wait to see
how they look from the inside from the air!

More info he http://www.glapinc.com
http://www.lpaero.com/

Jim Burns

Just FYI on a cleaning solvent. I found that Avgas make a very clean
solvent. I had some of this same type of black goo. I got rid of most of
it by a wooden tongue depressor then use avgas to clean up. Worked fine.

Safety alert - no open flames and lots of ventilation.
Regards, Ross
C-172F 180HP
KSWI


Jim Burns wrote:
As our Aztec was down due to a leaky prop seal, we began the install of our
new 1/4" side windows. After removing the plastic surround trim and mapping
the screws, because they were several different sizes and lengths, we then
had to remove the window retainers. The retainers are basically some fancy
L shaped aluminum pieces that when installed hold outward pressure on the
windows forcing them into the adhesive tape that Piper so liberally applied
when the plane was built.

Our old windows were a thermo pane design consisting of a 1/8" outer window,
then a space created by the retaining bracket, and a thinner inner pane of
Plexiglas finishing up the sandwich. I'm sure that Piper had good
intentions, but this design leaves no ability for cleaning the insides of
either the two panes. It also allows the panes to rub together and chafe,
creating a lot of crazing.

So after removing the window retainers, it was time to do some serious
cleaning. The adhesive is a fabric tape coated with 1/4" of a black tar
like substance that is nearly impenetrable with any kind of solvent. MEK
seemed to work a little, but most of the time it just made it smear. The
best method that we found was after scraping as much off with plastic putty
knives, we would create a small ball of the goo and then use it to dab onto
the window sill then briskly remove it so more black goo stuck to what you
held in your hand. Kind of like dabbing chewing gum off your kids face
after they blow a bubble. A second round of MEK cleaned things up very
nicely.

Most of the LP Aero windows fit right in, but the pilot's side window and
the cabin door window required roughly 1/4" be removed from two sides. A
fine toothed band saw blade worked well followed by finishing and beveling
with a belt sander with an 80 grit belt. LP was nice enough to notch out
the top of our passenger side center window due to the protruding rivets
along the top, but for some reason they forgot that the pilots side window
has the same rivets. Oh, well the bandsaw and the belt sander made quick
work of resolving that problem.

After dry fitting with the protective plastic still applied to the windows
we pealed the plastic off and then squeezed a nice thick bead of black
silicone to both the window frame and to the window itself. Being super
careful not to touch anything with the pre-gooed window, we slipped them
into position and then pressed them tight, forming a good seal letting the
excess silicone ooze out from around the edges. After mistakenly letting
the first two windows set overnight, we quickly learned that it is easier to
clean up the messy wet silicone immediately after installing rather than
letting it dry then cutting and scraping it off later. With fingertips
blistered from rubbing, lesson learned, not to be forgotten.

Reinstalling the retaining brackets was a no brainer. While the silicone is
still soft, fit into place, press against the window until the screw holes
line up, reinsert screws. No need to drill new holes for the thicker
windows, they simply took up the same thickness as the old thermo pane
design, but since Piper never installed 1/4" windows in the Aztec we
couldn't get away with the part 43 logbook sign off for simply "replacing
side windows". LP required a 337 for this install and notices about it were
plastered all over the packaging. Since we ordered them through our A&P -
Aztec owner friend, he filled this out and it was approved through the mail
and with a phone call as "previously installed under previous documentation
and approval in same make/model".

So with windows in and approved, now it's just a matter of refreshing the
condition of our 40 year old plastic trim. Plane Plastics demands roughly
$135 for each of the 5 pieces that surround the windows, so before spending
that kind of $$$ we decided to see what we could do with a fiberglass repair
kit and some spray paint. After searching the group posts and reading up on
what people were using to paint plastic and what SEM paint cost, I talked
with a couple A&Ps that work on many of the rental planes in the area.
Their paint of choice? Fleet Farm. (a local midwest farm and home supply
store) Good coverage, no pealing, no sticky residue and their Almond color
matches the old Cherokee off white, and the Sand pebble color matches the
old Cherokee tan color.

After sanding, prepping, patching, and reinforcing the screw holes with
fiberglass, a little sanding then cleaning with MEK, the first piece was
ready for the paint test. I must say that the cheap FF brand paint worked
as advertised. I gave it 3 light coats then let it dry overnight. Once
installed, the first piece looks as if it had just came out of the
factory... well almost, but a lot better than the hole $135 would have left
in my wallet.

Two more pieces ready to go in tonight, then just 2 more to go.

For those who have repeatedly contemplated how great their plane would look
with new glass but have had a fear of the costs, this is a project that you
really can take on yourself and do a nice job with. Total cost for us for
tinted 1/4" side windows will be less than $900. (note: we did not replace
the emergency exit center left window as it is a single piece design, rather
hard to replace, and was in excellent condition) In most cases, if your
side windows are an exact replacement, no A&P or 337 is required, just a
simple pilot sign off as part 43. The first thing that we noticed was how
the new glass made our paint job look even better. I can hardly wait to see
how they look from the inside from the air!

More info he http://www.glapinc.com
http://www.lpaero.com/

Jim Burns

As our Aztec was down due to a leaky prop seal, we began the install of our
new 1/4" side windows.
I had a little different experience with the Cherokee 140. All the glass
had already been replaced with 1/4 inch. So, when the 2 rear side
windows started to craze, I only had to clean up the replacement silicone.

The rear windows for the late model Cherokee 140 are very similar to the
middle windows of a Warrior. So, that is what LP sends you with a notice
that they will need "trimming". They needed pretty extensive trimming
and I also found the band saw to be the tool that was quick and afforded
the best control. The snag was that the curve in the 140 is a bit
different than the Warrior and it required some significant finger power
to press in the glass while installing the l-bracket holders.

I also cleaned up the glass with the windows "wet". These days, I use
the caulk cleanup tool that most home centers sell. It is WAY neater
than the "finger with alcohol" method. Quicker too. Under $2 for a
disposable tool, I have found no equal. In reality, I put on a pretty
neat bead and did not over do it, so there was little cleanup required.

Good Luck,
Mike

I can hardly wait to see
how they look from the inside from the air!

Thanks for the write-up, Jim. This one goes in my "keeper file" for future
use!
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"