Interior screws - C172G

I have a 1966 Cessna 172G and some replacement plastics from Vantage
Plastics. There are a number of missiong screws on the existing interior,
and the perfectionist in me is wanting to replace them along with the
plastics. Can anyone out there recommend the screw sizes that are typically
used for a Cessna interior? Vantage sells quantities of stainless screws and
washers, but I would like to either get a kit or minimize the number of
different screws that I have to order.

TIA,
Jake

On Oct 15, 9:03 pm, "news.west.cox.net"
wrote:
I have a 1966 Cessna 172G and some replacement plastics from Vantage
Plastics. There are a number of missiong screws on the existing interior,
and the perfectionist in me is wanting to replace them along with the
plastics. Can anyone out there recommend the screw sizes that are typically
used for a Cessna interior? Vantage sells quantities of stainless screws and
washers, but I would like to either get a kit or minimize the number of
different screws that I have to order.

TIA,
Jake

Typically #4 x 3/8" or so, but you might also find #6 and #8
screws. They are driven into the aluminum itself rather than anchor
nuts, and as the holes wallow out they are usually replaced with
bigger screws. Cheap setup. And to do the annual/200 hour inspections
you have to remove the interior stuff, which just tears those holes to
bits over the average airplane lifetime if you do the maintenance
properly. I wish Velcro had been available when they designed the
airplane.

Dan

And to do the annual/200 hour inspections
you have to remove the interior stuff, which just tears those holes to
bits over the average airplane lifetime if you do the maintenance
properly.

You have to remove the interior panels of a 172 to do an annual
inspection?

Dang. Makes me happy to own a Piper, where all we have to do is remove
(in the passenger compartment) the seats, the flap handle cover, the
back seat floor panel, and the rear bulkhead.
--
Jay Honeck
Iowa City, IA
www.AlexisParkInn.com
"Your Aviation Destination"

Jay Honeck wrote:


You have to remove the interior panels of a 172 to do an annual
inspection?

No, usually just the front two panels because that's where the fuel
lines run and there's some control cables in there. The front seats
have to come out but not the rear.

Newps wrote:


Jay Honeck wrote:


You have to remove the interior panels of a 172 to do an annual
inspection?


No, usually just the front two panels because that's where the fuel
lines run and there's some control cables in there. The front seats
have to come out but not the rear.
Actually, on the 172, the aileron cables run up the rear door posts, as
do flap cables on the manual flap models. If you don't remove the rear
seat, accessing these areas can be very difficult.

Happy Flying!
Scott Skylane

On Oct 16, 3:32 pm, Scott Skylane wrote:
Newps wrote:

Jay Honeck wrote:

You have to remove the interior panels of a 172 to do an annual
inspection?

No, usually just the front two panels because that's where the fuel
lines run and there's some control cables in there. The front seats
have to come out but not the rear.

Actually, on the 172, the aileron cables run up the rear door posts, as
do flap cables on the manual flap models. If you don't remove the rear
seat, accessing these areas can be very difficult.

Happy Flying!
Scott Skylane

There are elevator and rudder cables and pulleys under the
entire length of the 172's floor. If you don't yank the rear seat, you
can't get the carpet up and take the inspection panels off. Every time
we get another second-hand 172 we find the pulleys under there seized,
cables worn, an incredible amount of junk including mouse nests and
droppings (corrosive), dirt, oil, small stones (tracked in by people),
rags and lost hardware (risk of cable/pulley fouling), and so on.
Sometimes even tools.
The bottom end of the aft doorposts (immediately ahead of the
aileron cable pulley in that corner) has a tendency to crack in the
angle cutout. It's difficult enough to see the area with everything
pulled out, impossible without it. Any 172 with more than two or three
thousand hours is likely to be cracked in that spot, both sides, and
certainly cracked if it has seven or eight thousand. Cracks sooner if
operating off rougher surfaces. Cessna sells a reinforcement kit, but
it's a stinker to install. They say it's 20 man-hours per side, and
we've found that not far off. After we do a couple more we'll get that
down.
If you don't drop the headliner at least partway you can't
inspect the rubber fuel line connections. They harden and crack with
age and start leaking. Guess what you'll find someday when you go to
fly your airplane? Or maybe they'll start leaking in flight. Had that
happen once in an old 180. And the aluminum lines are often not
properly located and are chafing against the holes in the doorpost on
their way from the wing root, down past the aileron cable and into the
floor.
The bulkhead at the back of the forward baggage compartment
(or the back of the only compartment if it's a 172L or earlier) has
cracking problems, usually in the lower corners near floor level. Got
to take all the plastic out of there to get a good look.
If you don't take the rudder bar covers out, you can't get a
look at the bar bearings (they need lubing) or the fuel line where it
goes through the firewall (the RH steering rod comes awful close and
can chafe it. Could create nasty surprises in flight). Some airplanes
have had trouble with loose bar bearings or broken brake master
cylinder bracketry.
If you don't remove the side panels forward of the door you
can't see inside those doorposts. They like to crack around the door
hinge attach points and you can't see it on the outside. It's the
doorpost itself that cracks, inside the skin, in the bend radius by
the rivet line. Bottom hinge is worst, 1975 and later is worse, too.
Don't know why.
If you don't take the plastic console off you can't get a good
look at the trim mechanism, the aileron, trim and rudder pulleys (more
seizures, possibly fraying cables) and the fuel valve u-joints, which
have stupid little rivets that gradually wear out and could leave you
with no fuel control.
The skin and internal structure at the little fuel access step
forward of the door sometimes cracks. Got to have the rug up and
panels out to see that.
There's no substitute for taking the time to do it right. We
do it, it takes a couple hours longer, but we seldom have any snags in
between inspections. And we're always surprised, even though we
shouldn't be, at how easily all the controls move after we've cleaned
everything, freed up all the pulleys and bellcranks, and set all the
cable tensions to spec.

Dan

wrote in message oups.com...

There are elevator and rudder cables and pulleys under the
entire length of the 172's floor. If you don't yank the rear seat, you
can't get the carpet up and take the inspection panels off. Every time
we get another second-hand 172 we find the pulleys under there seized,
cables worn, an incredible amount of junk including mouse nests and
droppings (corrosive), dirt, oil, small stones (tracked in by people),
rags and lost hardware (risk of cable/pulley fouling), and so on.
Sometimes even tools.
.....
There's no substitute for taking the time to do it right. We
do it, it takes a couple hours longer, but we seldom have any snags in
between inspections. And we're always surprised, even though we
shouldn't be, at how easily all the controls move after we've cleaned
everything, freed up all the pulleys and bellcranks, and set all the
cable tensions to spec.

Dan


Nice write up! Thanks!

Dan D.