This article is kind of a continuation of an older article of mine, where I used ABS sludge and bondo to mold my 7" Xenarc display into the center console of my MK3 Jetta center console.  That took me a week or so, involving a ton of manual labor, and it looked great for about a day, until I actually installed it, and then it developed cracks and the different materials expanded differently and it ended up looking bubbly as well.

So, I wanted to somehow salvage the install without starting from scratch.  My plan was to simply encase the whole thing in a shell, so that any cracks or other issues that developed between the different plastics behind would not show and would basically not matter.  The material of choice here was fiberglass.

I chose to completely avoid the traditional fiberglass resin for many reasons, most importantly that it has nasty fumes and I don't have a good ventilated area to work in, and that it's a pain to work with for the first time.  Instead, I went with epoxy resin.  What I ended up with was from US Composites , their 635 thin epoxy resin and 3:1 ratio medium hardener.  The pot life (working time) is about 20-25 minutes, and it is supposed to cure fully in 8-10 hours.  Thus I had enough time to lay down plenty of glass with each application, and have it cure overnight.

Epoxy resin and hardener used

I purchased the fiberglass cloth on ebay.  I got some 1.38oz, and some 2.3 oz cloth.  This is a lot lighter than the cloth you'd find at an auto parts store, but it's way better in this application - I wanted an even shell that was only as thick as needed for reasonable strength.  These thin cloths (particularly the 1.38oz) are very flexible during application, and I was able to cover all the compound curves without much trouble at all.  My first application of cloth to the console was also my first application of fiberglass cloth EVER.  I decided to cut the cloth into strips about 1" wide and 4" long and cover everything with overlaps.  This worked out okay, but left quite a few seams to be sanded later.

At that point, I also experimented with trimming the excess cloth.  As it turned out, with these few layers it was very easy to trim everything to shape with only a typical utility knife.  I was surprised at how easily and smoothly it cut with a knife, I was even able to go back and 'shave off' excess along the edges, like whittling soft wood.  Although I'm sure it's not quite as easy with heavier cloth and more layers, I really found fiberglassing with these materials to be easy and enjoyable, which was not at all what I was expecting.

  (mosimage)
Console after first application of 2-3 layers of 2.3oz cloth

Yes, it's hard to see in that first one, but there are in fact 2-3 layers of fiberglass cloth on that, but it's so thin and transparent all you can see is the sanded bondo/plastic/paint underneath.  Even with only that much cloth, the console was noticeably stronger, showing no signs of cracking or separation when flexed, and feeling more rigid as well.   

For the next application, I decided to put the flexibility of the cloths to the test and cover the entire console with one large, single piece of cloth.  I used 2.3oz cloth for the first layer, and it was a slight hassle in the compound curves, but overall it went on quite smoothly.  I followed it with a layer of the 1.38oz cloth, in the hopes that the finer cloth would result in a smoother surface, and this lighter cloth had no trouble forming to the surface. 

   
Console after application of single-sheet layers of 2.3oz cloth and 1.38oz cloth

 The next day, I put down a layer of just resin.  I used a foam brush, and did as much as I could to get it as even as possible, to minimize the amount of shaping I had to do when sanding later on.

A close-up of the surface left after the final layer of resin

Next thing to do was sanding.  I started with 100 grit, then 150, then 220.  Using the utility knife came in handy, for larger blobs it was often easier to just shave them down with the knife than to sit there sanding for a long time.  I probably spent a couple hours sanding.  It was around this point that I started carving out the button holes again.  That is a rather tedious process, and I ended up just carving out two of them and leaving the rest for later.

Console after sanding

The next step was to lay down some paint.  I was anxious to get to this, because the first coat of primer really tells you a lot about how good your sanding work was.  

 
First application of primer

In all, I was very happy with how it looked when the primer was on there.  There were a few areas with pinholes and other minor defects, but overall it wasn't bad at all. 

 The next step was cutting out the button holes, which turned out to be a ton of work, mainly because I made a big mistake.  I laboriously cut out every button hole using a carbide PCB routing bit with my dremel.  I then realized that with over 1/8" of resin and glass built up over the button area, I couldn't push the buttons anyway, so I used a dremel drum sander bit and sanded the whole area right down to the plastic bezel.  Had I done this before carving out the button holes, I probably could have cleared them by simply chipping out a small amount of remaining epoxy.  I would have saved an hour or two, and not ended up with slightly mangled button holes.  Live and learn...

   
 Button holes after rough cutting, as well as after sanding and bondo

Closeup of button holes after majority of finish work... Not perfect, I know, but really not noticeable in person, in my opinion.

By the way, don't do what I did, and use non-sandable primer, if you can help it.  When you need to sand it, it clogs the paper and is just a pain.  The story at this point gets boring again, because it's just tedious work for a while.  Lots and lots of sanding and shaping, followed by some bondo, more sanding, some glazing/spot putty for the pinholes, and more sanding.  I went from 100 grit to 220 grit sandpaper during the shaping and dry sanding.  After applying the spot putty, I switched over to wet sanding, starting with 220 grit and then following with 400 grit.  During wet sanding I ended up sanding off basically all the primer.  The big advantage of wet sanding, as I soon discovered, is that instead of clogging the sandpaper, even this terrible primer came off easily with the water and could be wiped away with a paper towel.  The finish of the fiberglass after wet sanding is incredibly smooth.  Once again, the transparency of the fiberglass makes it hard to see how good the finish really is, but primer tells a much better story.

With primer on, everything looked quite good.  I fully expected to be doing a bit more sanding after this coat of primer, but I don't think there's much left that needs to be done.  I'll use a little spot putty and do a quick once-over with wet sanding, but all in all I think it's almost ready for some decent paint.

Well, I got a bit lazy and impatient and installed it before doing the real paint work.  I ran into some issues with some droplets of epoxy on the back side of the screen shell that were pressing on the touchscreen when I reassembled it and caused it to fail to calibrate, but these were easily taken care of by scraping the excess epoxy with a knife.