[GMCnet] FRP for headliner

[Skip Hartline via Gmclist]

Good afternoon all,

Since the beast will be in dry dock for at least another month I've decided to tackle the headliner replacement. Anyone out there that has used FRP
got any ideals and suggestions. I've got the basics figured out but haven't heard if the FRP needs any kind of luan for backing or is the FRP rigid
enough on it's on. Any ideals will be greatly appreciated.

Skip Hartline
--
74 Canyon Lands, FiTech,
3.7 FD, Manny Tranny,
Springfield Distributor,
2001 Chevy Tracker Ragtop Towd

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[Ken Henderson via Gmclist]

Skip,

I did an FRP headliner several years ago in the X-Palm Beach my son now
has. It's standing up extremely well, as expected from its imperious
nature. I don't remember a lot about the installation except for one
point: Don't count on securing anything, like light fixtures, to ONLY
FRP. It isn't thick enough to hold screws well on its own. Anywhere you
plan to install such things should be backed up with plywood or other good
screw-holding material. Because those things go in last, you must plan
ahead for the location and configuration of those "backers" and secure them
in place with Liquid Nails or similar adhesive.

I was concerned about the acoustic properties of the hard FRP surface, but
according to my son and family, the interior acoustics are good (but they
have nothing to compare it to).

Ken H.

[Todd Sullivan via Gmclist]

I used some frp panels to replace sections of failing headliner in my last
coach. What Ken mentions about screw holding ability are true however
fastening to frp is easy if you use j nuts. If you try to carry too much
span the weight of the frp will cause it to droop. I cannot remember the
spacing at which I pinned mine to the roof stringers but I believe it was
every other roof stringer.

Sully
Bellevue wa.

[Larry via Gmclist]

This is what I used. Adds an R3 insulation value, plenty stiff. I glued Hull-liner to it. to give it a soft look and for sound absorption. JWID

http://www.gmcmhphotos.com/photos/g4446-new-ceilings-or-headliner.html
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.

[James Hupy via Gmclist]

Best ceiling I ever saw in a GMC a wood worker/shipwright did to his coach.
Longitudinal strips of teak about 1" wide, with occasional lateral strips
of a lighter colored steam bent wood that fit the curve of the interior
roof. Looked like a Chris/Craft or Garwood yacht from the 30's or 40's.
Truly outstanding fit and finish. Would have taken me a couple of years to
do. Don't know how long it took him, but, all the interior cabinets were
much the same quality. Left me speechless.
Artisans like him are few and far between. I can think of two in our
world. Hal St.Clair, and a guy named Pinkerton. Stand in awe when around
either of them, you are in the shadow of greatness.
Jim Hupy
Salem, Oregon

On Sat, Apr 11, 2020, 12:26 PM Larry via Gmclist <gmc...@list.gmcnet.org>
wrote:

[Len Novak via Gmclist]

Try 3/16 ABS plastic with a pebble finish. Bulletproof!

Len and Pat Novak
1978 GMC Kingsley
The Beast II with dash lights that work and labels you can see!
Fallbrook, CA new email: B52...@Roadrunner.Com
http://www.gmcmhphotos.com/photos/showgallery.php?cat=4375

www.bdub.net/novak/

--
This email has been checked for viruses by AVG.
https://www.avg.com

[Gerard Hickey via Gmclist]

I purchased my coach almost exactly one year ago and it has FRP
installed for the headliner. Actually did not know what FRP was and had
to go look it up. I can say it is an excellent headliner material and
the acoustics within the coach are perfectly normal. No hard sounds or
echoing at all. I have been quite happy with it.

I have all of the headliner out right now to rewire everything. It had
metal strips at each cross member to hold the FRP up and that was
perfectly fine. There were no dips or points that concerned me. The
straight FRP held at the cross members is rigid enough, but then I have
nothing hanging from just the FRP. I would agree that if you are going
to hang anything that it will need to be braced as the FRP will not be
strong enough to support much more than its weight. I suppose if you are
hanging something that is a pound or so, you might get away with it.

When I pulled out my FRP, I did find that there were 2 pinch points
which caused me to splinter 2 panels. I will need to cut two new ones
and replace them. One was just inside the door against the side of the
refrigerator and the other was above the closet. In both cases I have
been considering using a jack to try to lift the roof up about an 1/8 of
an inch so that I can get the replacement FRP installed.

I have been planning on putting the FRP back in, but I like the idea of
the Durotherm Lite that Larry used. I like the thought of getting a bit
more R factor into the ceiling. Now if I can find some of that out here
on the west coast (around Seattle).

Good luck.

--
Gerard Hickey / WTØF IRLP:3067/Echolink:529661
hic...@kinetic-compute.com DMR: 3102272
425-395-4554

[Thomas Phipps via Gmclist]

On my 1975 GMC, Interior by Avion, I used a product called Komotex. It was 6mm thick and is metric sized sheets. Bigger than a 4'x8' sheet of 1/4"
ply, or Luan. I had called the supplier and asked for 4'x8' sheets, without think of it's actual size. I did ask for the cutoff pieces from the
dealer. A good move. I used 3 full sheets, plus most of the cutoff sections. I had purchased 5 sheets.
This material is 100% waterproof, cuts easily, flexible but does not need support behind it. Has a nice surface finish, smooth on one side and
slightly rough on the other, so it's your choice. I was able to suspend interior lights, without deforming the material from
the ceiling. It will burn, but once the flame is removed, it self-extinguishes. Komotex is used for the outside sign business, so appears to be
durable.
P.M. me a mailing address, and I'll send you an envelope sized piece
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG

[Jim Felich via Gmclist]

Thomas,
Where did you buy the Komatex?
How flexible is it?
Please send me a piece.
Jim Felich
209 Golf Club Drive
Santa Cruz, CA 95060

Thank you.

[Skip Hartline via Gmclist]

Thanks for all the replies, there's a lot more options out there, more than I realized. Any more out there will be welcome.

[Ed Clerkin via Gmclist]

How difficult is it to remove the overhead cabinets? I need to replace all of the duo-blinds as they disappear up behind each cabinet. I am fairly
certain the original owner had custom cabinet refacing.
--
Ed Clerkin | 1974 GMC Canyon Lands 26’

[Johnny Bridges via Gmclist]

They're held in place with bolts whichanchor in Rivnuts<tm> in the structural aqluminum. Much easier to get down if you have a helper to hold the
cabinet while you back the bolts out. If a Rivnut spins with the bolt, use a cutoff wheel and take the head off.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell

[Ed Clerkin via Gmclist]

Johnny Bridges wrote on Wed, 15 April 2020 05:54

> They're held in place with bolts whichanchor in Rivnuts<tm> in the structural aqluminum. Much easier to get down if you have a helper to hold the
> cabinet while you back the bolts out. If a Rivnut spins with the bolt, use a cutoff wheel and take the head off.
>
> --johnny

Ok, thanks. So the rivnuts likely look similar to the ones used on the roof clearance lights.

Oh, the original owner shaved off the rivnuts for the gas door where the magnet is attached. I am guessing it was for clearance reasons with those
huge CA emission fuel pump nozzles back in the 70's-80's. I have an OEM magnet that I want to reattach but not sure what size rivnut to purchase. Are
those holes accessible inside the cab behind the trim panel next to the driver seat?

--
Ed Clerkin | 1974 GMC Canyon Lands 26’

_______________________________________________

[James Hupy via Gmclist]

That looks like a natural place for "pop" rivets. That is aluminum up where
the gas cap door is.
Jim Hupy
Salem, Oregon

[Larry via Gmclist]

Richard RV wrote on Wed, 15 April 2020 22:14
> Larry wrote on Sat, 11 April 2020 12:25

> > This is what I used. Adds an R3 insulation value, plenty stiff. I glued Hull-liner to it. to give it a soft look and for sound absorption.
> > JWID
> >
> > http://www.gmcmhphotos.com/photos/g4446-new-ceilings-or-headliner.html
>

> Larry,
> I like the Duro-Therm H-section divider molding.
>
> https://www.menards.com/main/mouldings/panel-mouldings/durotherm-trade-lite-durolam-lite-white-divider-moulding-for-wall-panels/mld2066p/p-14444506063
> 92.htm
> The narrow visible section would give a nice clean look if you were putting up the board by itself.
>
> What did you use at the seams with the hull liner applied?
>
> Richard

When I did this, the Duro-Therm H-section divider molding, was not available, but some like stuff was. Got it also at Menards in with the moldings.
The stuff I used is just like the Duro-Therm H-section divider molding but with a narrower back side. You just gotta take some time to look through
all of the moldings and pick what looks like it would work.

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.

[Larry via Gmclist]

BTW, when I put the Duro-Therm up, I measured between the electric channels on either side of the coach bending the tape measure to follow the curve
of the roof. I took that measurement and added a couple of inches. Then placed the edges of the Duro-Therm at the electric channels and tried to
"POP" the ceiling into place. If I could not pop it, I shaved a little off of the edge and tried again. Shaved a little...tried to pop...shaved a
little...tried to pop. Finally got the right width of Duro-Therm so that it popped firm into place against the roof ribbing. Doing that, eliminates
the need to somehow screw...glue...whatever.. it in place while you try to put the cabinets etc up. Take pictures of the ceiling with dimensions of
where the ribs are so you can find the ribs when the cabinets have to go up. Then, I used an icepick to poke through the Hull Liner/ Duro-Therm to
verify rib location before I put self tapping screws through cabinet into the ribs. Sorry, no pictures. I was so intent on NOT running a screw
though the roof that my concentration kept me from the camera. :roll: JWID

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.

[Todd Sullivan via Gmclist]

I don’t know if I would trust a sheet metal screw to stay tight in the thin
aluminum ribbing with the weight of the cabinet hanging there. Using the
existing (or added) nutserts and a machine screw more dependable.

My 2c

Sully
Bellevue wa.

On Thu, Apr 16, 2020 at 7:04 AM Larry via Gmclist <gmc...@list.gmcnet.org>
wrote:

> BTW, when I put the Duro-Therm up, I measured between the electric

[Will via Gmclist]

FRP will droop in the center. Its not horrible, but bothered me enough that
i added additional strips in the center.

[Larry via Gmclist]

Richard RV wrote on Thu, 16 April 2020 13:04
> Thanks for the write up, Larry. Are the sheet metal screws holding up the cabinets or just the Duro-Therm?
>
> Definitely would like to see it in person next time I see you. Hopefully that'll be sooner rather than later.
>
> Richard

Richard, I used 1/4 X 2 1/2 self tapping hex head screws. Also used 1/8" X 1" Aluminum bar stock inside of the cabinets running the full length of the
inside of cabinet. So, screws went through the aluminum stock, through the cabinet frame, and through the Duro-therm, into the roof ribs. Spent a lot
of time locating the ribs and carefully measuring location of the ribs. Predrilled the aluminum stock, the cabinet frame, and Duro-Therm to make sure
the rib was under there. One screw in every rib there. Had a friend with a good mechanical/construction/common sense background helping me.

[Larry via Gmclist]

Richard RV wrote on Thu, 16 April 2020 15:01
> Larry wrote on Thu, 16 April 2020 12:32

> > Had a friend with a good mechanical/construction/common sense background helping me.
>

> Damn, Larry - that's how I describe you! I really want to meet your friend now. :)
>
> Richard

Richard RV...hummm Richard Valinotti?