Re: polycarbonate search continues...help and some pilot house questions
J,
I used to see it stocked either in Lowes or Home Depot in the
Charlote, NC area. I remember seeing bronze and grey in 1/4 thickness.
Lewis
--- Inbolger@yahoogroups.com, "Jason Stancil" <jasonstancil@h...>
wrote:
I used to see it stocked either in Lowes or Home Depot in the
Charlote, NC area. I remember seeing bronze and grey in 1/4 thickness.
Lewis
--- Inbolger@yahoogroups.com, "Jason Stancil" <jasonstancil@h...>
wrote:
> OK-with
>
> the pilot house is just days from going up and i can't find any
> stinking tinted polycarbonate for less than 8 billion dollars. Ebay
> is'nt happening. Someone know a source?
>
> How bad does acrylic suck......it's so cheap an abundant. How about
> the so called marine acrylic, like harbor freight and others sale?
> If i'm real careful with cutting and mounting the windows will
> Acrylic work? Any experieces with the stuff, good or bad?
>
> I was going to strip build my pilothouse for a lovely bright
> finished bit o' flair but after strip laminating the two hatches
> i've had enough, looks like i'll stich and glue the pilot house
> some mdo with a bit of light framing and finish with paint.
> Suggestions? On how not to screw it up.
>
> Jason
The difference between polycarbonate and acrylic (i.e. plexiglass) in
handling is maybe of an even larger order than the difference between
acrylic and glass. Polycarbonate is very abusable (I have polycarbonate
bicycle helmets), but you have to be very careful with acrylic or it
will crack. Acrylic is moderately strong if not scratched or drilled.
You can take a 1/16" thick piece of polycarbonate on standoffs and smack
it with your fist (at least moderately hard, I didn't have the courage
to really smash it).
I should think on a boat where you are counting on big windows holding
back water for stability, polycarbonate would be comforting. Plus it
would save you quite a bit of trouble. Might be important to check into
sun resistance.
Get two little pieces and try to break off a corner with pliers or a
hammer. You will see what I mean.
handling is maybe of an even larger order than the difference between
acrylic and glass. Polycarbonate is very abusable (I have polycarbonate
bicycle helmets), but you have to be very careful with acrylic or it
will crack. Acrylic is moderately strong if not scratched or drilled.
You can take a 1/16" thick piece of polycarbonate on standoffs and smack
it with your fist (at least moderately hard, I didn't have the courage
to really smash it).
I should think on a boat where you are counting on big windows holding
back water for stability, polycarbonate would be comforting. Plus it
would save you quite a bit of trouble. Might be important to check into
sun resistance.
Get two little pieces and try to break off a corner with pliers or a
hammer. You will see what I mean.
>MJason Stancil wrote:
>snip
>
>How bad does acrylic suck......it's so cheap an abundant. How about
>the so called marine acrylic, like harbor freight and others sale?
>If i'm real careful with cutting and mounting the windows will
>Acrylic work? Any experieces with the stuff, good or bad?
>
>snip
>
I've had a 1/8" acrylic windscreen on the Cessna for thirty years and it's
still useable. It has been sheltered from the sun for most of that time,
but it has withstood really heavy rain at over 120 mph. (Ellen thought it
was hail, but I explained that if it were hail, we'd be dead.) Ice build-up
and defrost heat haven't phased it, nor has the 1200 hours of 4000+ gusts
per minute from the propeller blast. Life would be much quieter with 3/16"
thickness.
There definitely are tricks to working with the stuff. Polycarbonate can be
worked like wood. Acrylic requires a deft touch. Primarily, one can't cut
it in the normal way. A cutting instrument such as a chisel, drill, saw, or
whatever acts as a wedge to create a split that runs along ahead of the
tooth. In acrylic, it runs way ahead, usually in a direction you don't
want. One must cut by scraping; e.g. pull the saw backwards, use spade bits
in a hand auger, etc. I've tried burning/melting with a soldering gun and
while it works, cleaning up the resulting mess is too tough and the process
stinks, literally.
After the acrylic is cut, one must polish the edge to remove all scratches.
Even the tiniest will start a crack down the road. Wet sanding works well,
progressing to 600 grit and then buffing.
Work slow! If the tool gets hot, the plastic melts and sticks to the edge.
You don't want this to happen. Note that there's both the friction
generated heat and that generated by "parting energy;" i.e. the work it
takes to separate the molecules from their stable, un-cut, state.
Drill all mounting holes well oversize and capture the plastic between
"fender" washers, preferably with additional rubbery washers to prevent
leaks and scratching. As the plastic flexes under load, it must not come in
contact with the fasteners. I used to get a kick out of watching the dirt
line on my friend's Grumman Tiger. As we would roll for take-off, the
canopy would develop lift and the dirt line would move up at least one half
inch from its rest position along the edge of it frame.
Scratches are deadly, but can be buffed out with such as MirroGlaze.
Prolonged exposure to the sun (years tied down outside) will result in
crazing, but a canopy cover will cause scratches as it flaps in the wind and
moves the embedded dirt.
Roger
derbyrm@...
derbyrm.mystarband.net/default.htm
still useable. It has been sheltered from the sun for most of that time,
but it has withstood really heavy rain at over 120 mph. (Ellen thought it
was hail, but I explained that if it were hail, we'd be dead.) Ice build-up
and defrost heat haven't phased it, nor has the 1200 hours of 4000+ gusts
per minute from the propeller blast. Life would be much quieter with 3/16"
thickness.
There definitely are tricks to working with the stuff. Polycarbonate can be
worked like wood. Acrylic requires a deft touch. Primarily, one can't cut
it in the normal way. A cutting instrument such as a chisel, drill, saw, or
whatever acts as a wedge to create a split that runs along ahead of the
tooth. In acrylic, it runs way ahead, usually in a direction you don't
want. One must cut by scraping; e.g. pull the saw backwards, use spade bits
in a hand auger, etc. I've tried burning/melting with a soldering gun and
while it works, cleaning up the resulting mess is too tough and the process
stinks, literally.
After the acrylic is cut, one must polish the edge to remove all scratches.
Even the tiniest will start a crack down the road. Wet sanding works well,
progressing to 600 grit and then buffing.
Work slow! If the tool gets hot, the plastic melts and sticks to the edge.
You don't want this to happen. Note that there's both the friction
generated heat and that generated by "parting energy;" i.e. the work it
takes to separate the molecules from their stable, un-cut, state.
Drill all mounting holes well oversize and capture the plastic between
"fender" washers, preferably with additional rubbery washers to prevent
leaks and scratching. As the plastic flexes under load, it must not come in
contact with the fasteners. I used to get a kick out of watching the dirt
line on my friend's Grumman Tiger. As we would roll for take-off, the
canopy would develop lift and the dirt line would move up at least one half
inch from its rest position along the edge of it frame.
Scratches are deadly, but can be buffed out with such as MirroGlaze.
Prolonged exposure to the sun (years tied down outside) will result in
crazing, but a canopy cover will cause scratches as it flaps in the wind and
moves the embedded dirt.
Roger
derbyrm@...
derbyrm.mystarband.net/default.htm
----- Original Message -----
From: "Jason Stancil" <jasonstancil@...>
> How bad does acrylic suck......it's so cheap an abundant. How about
> the so called marine acrylic, like harbor freight and others sale?
> If i'm real careful with cutting and mounting the windows will
> Acrylic work? Any experieces with the stuff, good or bad?
Jason Stancil <jasonstancil@...> wrote:
Item 3827068977 on ebay, ending in two hours
is for tinted polycarbonate. That is the same seller
that I used. Those pieces are too narrow for the
big side windows, but would work for the front
and back windows. I used 1/8" thick and was happy
with the strength, and Bolger approved of the that
dimension, except for the cosmetic only objection that
it flexes.
Acrylic cracks every time I work with it, maybe with
more skill it could be used. I would be tempted
to use glass if my only other option was acrylic.
> stinking tinted polycarbonate for less than 8 billion dollars.No doubt about it, polycarbonate is expensive.
Item 3827068977 on ebay, ending in two hours
is for tinted polycarbonate. That is the same seller
that I used. Those pieces are too narrow for the
big side windows, but would work for the front
and back windows. I used 1/8" thick and was happy
with the strength, and Bolger approved of the that
dimension, except for the cosmetic only objection that
it flexes.
Acrylic cracks every time I work with it, maybe with
more skill it could be used. I would be tempted
to use glass if my only other option was acrylic.
OK-
the pilot house is just days from going up and i can't find any
stinking tinted polycarbonate for less than 8 billion dollars. Ebay
is'nt happening. Someone know a source?
How bad does acrylic suck......it's so cheap an abundant. How about
the so called marine acrylic, like harbor freight and others sale?
If i'm real careful with cutting and mounting the windows will
Acrylic work? Any experieces with the stuff, good or bad?
I was going to strip build my pilothouse for a lovely bright
finished bit o' flair but after strip laminating the two hatches
i've had enough, looks like i'll stich and glue the pilot house with
some mdo with a bit of light framing and finish with paint.
Suggestions? On how not to screw it up.
Jason
the pilot house is just days from going up and i can't find any
stinking tinted polycarbonate for less than 8 billion dollars. Ebay
is'nt happening. Someone know a source?
How bad does acrylic suck......it's so cheap an abundant. How about
the so called marine acrylic, like harbor freight and others sale?
If i'm real careful with cutting and mounting the windows will
Acrylic work? Any experieces with the stuff, good or bad?
I was going to strip build my pilothouse for a lovely bright
finished bit o' flair but after strip laminating the two hatches
i've had enough, looks like i'll stich and glue the pilot house with
some mdo with a bit of light framing and finish with paint.
Suggestions? On how not to screw it up.
Jason