Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×

Thread Tools Search this Thread Display Modes
Old 01-24-2010, 05:28 PM   #1
2 Rivet Member
1969 21' Globetrotter
Cambridge , Massachusetts
Join Date: Sep 2007
Posts: 50
Floor replacement. Keep me from going down the wrong street. AGAIN.

Unlike other threads which talk about tongue and groove or lap joints in 5/8 plywood, the existing floor in my '69 GT was 3/4 plywood with butt joints connected through plywood splice plates about 6 wide glued to the underside. Generally, every other cross frame is set low to accommodate the thickness of these plates. Has anyone else seen this type of installation? Here is how I propose to proceed with the floor replacement. At this time, the inner skin and floor is out, the belly pan is off, the wheel wells are out and the only connection between the shell and the frame is across the front where a formidable steel plate is installed to prevent frame separation. The shell is supported by a system of shores between the frame and underside of the shell roof. After completing repairs to the frame, priming, painting, replacing the axle and the wheel wells, I will start replacing the floor. This will involve gradually shimming the shores so that the separation between shell and frame varies from 3/4 in front to 2 or 3 at the rear. I will then install the floor with five pieces of plywood running the width of the trailer (about 92) starting at the front. I will use the same method of joining the pieces as was used originally (see above). I realize that this will require selective removal and replacement of the shores as each piece of plywood is installed. Once the floor is in place and interior bolts installed, the shell will be lowered into place and secured to the frame at the outriggers and to the floor only with screws elsewhere. I do have some questions. First, what are the potential pitfalls of this approach? Second, vinyl resin has been recommended to seal the edges (and perhaps the entire underside) of the floor. No West Marine is nearby. Is it acceptable to use the resin sold with the fiber glassing kits at the big box stores that costs about $35 per gallon? They don't mention that it is vinyl. Finally, does anyone know what the width of the original floor in a '69 GT was?


Since this post is already too long, I have not related how my first approach to replacing the floor ended in failure. Let me know if you would like to hear this cautionary tale.
JoePfznik is offline   Reply With Quote
Old 01-24-2010, 06:09 PM   #2
2 Rivet Member
ltenbrink's Avatar
1968 30' Sovereign
Lorton , Virginia
Join Date: May 2009
Posts: 58
Hi John. My '68's flooring was installed just as yours was, so you're not alone. I admit I'm not going to say how I replaced the floor because there may be an outcry (it really goes against the grain of lots of people here) but your concept looks like the best true shell on replacement I've come across! I stayed with the butt joints and the "shim" underneath the joint like the original design also.

And I'll be back on in 10 years to let me know if my subflooring replacement concept worked out well...
ltenbrink is offline   Reply With Quote
Old 01-24-2010, 07:54 PM   #3
Rivet Master
65CV's Avatar
1959 26' Overlander
Western , Massachusetts
Join Date: Sep 2005
Posts: 1,468
Images: 6
A little concerned


"Once the floor is in place and interior bolts installed, the shell will be lowered into place and secured to the frame at the outriggers and to the floor only with screws elsewhere."

I assume that you will bolt the floor to the frame using elevator bolts and that this is what you mean by "interior bolts".

One of the best visuals I've found on construction is post #20 of this thread:

On my '65, I found that the c-channel was trash and had to make up a new one. I would definitely inspect it well, replace if necessary and buck rivet the shell to that c-channel and NOT use screws to connect the shell to the frame. It's a critical part of the monocoque construction.

On Epoxy, you're not confusing West Marine with West Systems Epoxy, are you? They are totally separate companies. West Marine is not the only place to get West Systems Epoxy. Head east to a good boat store if you want to find it, you're not far from the water.

The previous thread I mentioned and this are great resources:

Be careful, you're on a critical part of your project. Research it well!

Good luck.

65CV is offline   Reply With Quote
Old 01-24-2010, 07:59 PM   #4
Rivet Master
Wabbiteer's Avatar
1973 27' Overlander
1972 29' Ambassador
Itasca , Minnesota
Join Date: Apr 2006
Posts: 2,044
Images: 2
Blog Entries: 2
The Bondo box store resin is a polyester - and would be better than paint but not by much. "Polyester resin is the cheapest resin available in the marine industry and offers the poorest adhesion, has the highest water absorption, highest shrinkage, and high VOC's"

I used 700 Vinyl Ester Resin which is extremely hard resin - the vinyl ester is superior when you want to encapsulate medium and large grain woods, fine grain woods like cedar and redwood should have epoxy. The price has gone up some but not much.

VE withstands higher temperatures (250F+) than epoxy or polyester. I thinned the first coats with 5% xylene and watched the endgrain soak it in - took 3 coats before it stopped wicking in. I finished both sides - the clear glass coat on the inside is a bit brittle, drop a heavy tool and it cracks a birdseye but the plywood is failing, not the resin.

No clue about your floor width...

The days are short and the night is long and the stars go tumbling by.. . ~Airstream~
Wabbiteer is offline   Reply With Quote
Old 01-25-2010, 07:11 AM   #5
Rivet Master
Aerowood's Avatar
1971 21' Globetrotter
Arvada , Colorado
Join Date: May 2006
Posts: 3,045
I did a complete floor replacement on my 71 GT on this thread

Aerowood is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
sub floor replacement help Terry J Repairing/Replacing Floor &/or Frame 13 06-26-2010 09:50 AM
Floor replacement 68GTAir Repairing/Replacing Floor &/or Frame 2 08-17-2009 08:58 PM
Floor replacement Dman Repairing/Replacing Floor &/or Frame 3 03-07-2008 02:35 AM
Floor replacement Over59 1960 - 1964 Overlander 5 09-12-2004 01:24 AM
floor replacement daves clipper Repairing/Replacing Floor &/or Frame 18 01-04-2004 06:26 AM

Featured Campgrounds

Reviews provided by


This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.

All times are GMT -6. The time now is 10:44 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.