Wednesday, April 5, 2017

The Floor Goes In.

1996 SD 16' rehabilitation. New floor. The previous floor was 1/4" (6.25mm) chipboard with fiberglass over top. We decided to go with 1/2" thick marine grade plywood where we could (upper level in back), or two layers of 1/4" marine grade laminated together (everywhere else).
Prepped upper area with all holes covered with fiberglass except for table leg receptacle holes.

Using paper to make a template.

Template on the 1/2" marine grade plywood. I marked out a few of the previous attachment holes to help with alignment. I drilled these in the wood too.

I set my jigsaw to a 30" angle. The edge of the plywood will match the fiberglass radius more easily this way. Also, for any areas of fine adjustment, then I can trim the edge off with a knife (since it will be a thin edge due to the angle).

Cut out.

I used a belt sander to feather out the edges a little more. note the three screws that I can use for alignment in the trailer.

After a few in and outs with the plywood, it fit well enough. the screwdrivers are through the plywood and in the old holes.

Note that I also drew the frame lines on the panel. This is so I can see them from inside the trailer when I am attaching things back to the frame for the placement of new screws.

I had mentioned the bathroom enclosure in another post. Back and forth it goes as I work in one area or another.

The lower area is 8'-6" long by about 5'-8" wide. So... can't be done with one sheet. I didn't like the seam in the previous flooring, so I decided to use 1/4" sheets of plywood cut to overlap each other.

Draw everything out! Measure twice... cut once. (If only I listened to that advice...)

Cutting out the various shapes to get the overlapping pieces.

In and out... in and out... getting that edge to the right outline, and feathered out below correctly to match the radius of the trailer fiberglass.

More feathering with the belt sander.

After enough test fits, the pieces fit well.

Fitting well.

Now... to plan out which pieces I can laminate before I take them in. The Casita door only allows certain sized pieces in!

Frame lines on the upper layer for future reference.

And... notes to NOT drill into the holding tank!!!

In order to laminate it inside, I wouldn't be able to clamp. So I predrilled a bunch of small holes so I could put 1/2" screws in to hold the layers together.


What I'm using for fiberglass work, for coating wood to waterproof it, and also to laminate the plywood.

I should also mention that before I fiberglassed the holes from the inside, I put some paper under the Casita. I didn't want to glue it to my garage floor.

Showing how the pieces go together.

Laying down epoxy to laminate the piece that goes above it.

Screwing the piece down to the one below it.

What it will look like together.

Showing how it comes apart. These are the two pieces I need to get into the Casita.

Coating the bottom and edges with epoxy to further waterproof the marine grade plywood.

Don't forget that it gets a shower pan and toilet!

The shower pan has a beveled edge to allow it to drain to center. Angle grinder with a sanding disc.

Putting the shower pan and black water tank on top for a test fit.

Further sanding based on test fit.

Here's what it looks like before the floor goes in.



This shows the bottom layers in place. They already had the side pieces glued onto them.

Adding epoxy before I add the central top piece.

Moving the central top piece into the Casita.

Last chance to look...

Top piece in place and being screwed down to set it into the epoxy and laminate it to the lower piece. Floor is in!!

On to the Gelcoat for the top half!!

"Spot" treatment of hairline cracks. Use a dremel to drill it out, leaving a V-shaped profile to allow gelcoat to get in there. (you can see the hairline crack about the be ground out behind the grinding bit)

Ground out hairline crack.

In the middle/lower right, you can kind of see some filled lines. It will take a few coats of gelcoat to get them level with the finish and then they'll disappear.

Due to the condition of the gelcoat overall, I decided to spray gelcoat the entire top half. The easiest way to mask seemed to be on the inside, pinching the paper between the carpet and the fiberglass.

Not easy to do at first, but I developed a system. Get the top in, and pin through the two rivet holes to secure the top of the masking paper.

Then go inside, and slowly get the paper between the carpet and fiberglass. I needed to run a knife between to separate them. I'll reglue them when I put the windows back in. I'll use 3M Super 77 spray glue.

Pulling the carpet away to get the paper in.

Adding tape in a few spots to get it to stay.

Now... back to the beginning. This is an earlier photo of the outside of the Casita.

I decided to take of the decals. They left obvious lines, since they had been protecting the gelcoat from the sun, oxidizing and being dinged.

This is where I started to sand the whole thing. The oxidation and pitting was fairly significant. You can see the top back still has some shine, I hadn't gotten there yet.

Now I'm getting serious, windows are off and I'm committing to doing the whole thing to get it as perfect as I can.

Sanding and gelcoating areas.

Most repaired areas are gelcoated to bring the surface up to 'level' in those areas.

You can see the condition of the gelcoat at the top of this photo (and what removing a stripe left behind). I'm using a Festool orbital sander with 60 grit sandpaper. Knowing I'm going to recoat, I went aggressive. 120 also worked pretty well. (FYI... while expensive, the Festool sander is amazing for it's dust control system!!!)

A close up of sanding, with before at top, after at bottom.

Spraying gelcoat. Overall it went pretty well. There's more orange peel than I'd like. I used 1.5% MEKP, and thinned the mixture with 10% acetone to get it to spray better. My HVLP spray gun has a 1.4mm nozzle (smaller than ideal), and I was spraying at 40PSI with a compressor that is smaller than I should have for this (to provide sustained pressure). A wider nozzle, and a compressor with larger volume capacity would have been much better. I had to wait a fair amount on my compressor to get back to pressure during spraying. I was worried that my gelcoat would begin to harden in the gun, but it didn't. I sprayed about 900ml of it over about 20 minutes I think.

Looks good from a distance!
 

Top looks soooo much better. It started out all oxidized, pitted, sappy and dirty...

You can see the level of orange peel in these photos. I'm going to wipe it all down with acetone again to get the wax off (it's a gelcoat with wax in it that it needs to cure - it rises to the surface and forms a coating under which the curing happens) and give it another coat. That will ensure I have a good layer of gelcoat to allow some significant sanding. This time I'll start with 120 or a finer sandpaper. The goal is to take it down as little as possible to get the pits out.

More orange peel look on it. The next step is to put on another coat, and then get to sanding and finally buff it till it shines!!