Initial fiberglassing, final filling and fairing

If you think my recent messing around with the light mast and the railings were thinly-disguised excuses for not tackling the scary-nasty work of finishing the fiberglassing on the top, you are right.  I have put this work off about as long as I can. I started on it again yesterday. 

Following is a journal of fiberglass progress on the top project, starting with application of glass fabric in early March, through today. I plan to go all the way through the rest of the work in marathon fashion over the next few days.

3/7/12

1-5 p.m.

• Laid out and smoothed two 50-inch by 12-foot sheets of 6-ounce fiber glass fabric, overlapping fabric about 8-inches fore and aft down the centerline. No stapling was necessary to hold the fabric in place.

• Wetted out the fabric from centerline to the edges with epoxy resin, smoothing the application and removing bubbles. This was a three-man job, with one person mixing 6-ounce epoxy batches and the other two wetting out fabric and spreading un-thickened epoxy.

• The remainder of the top finishing work was done single-handed, except for two occasions when helpers were needed to move the top or flip it over.

3/10/12

2-5 p.m.

• Cut off excess glass cloth with a utility knife. Sanded edges. Bedded 6-ounce fiber glass tape in epoxy resin to reinforce edges.

3/29/12

2-4 p.m.

• Thorough sanding of entire top. 80-grit sandpaper on a random orbit sander
• Tacked with cloth dampened with acetone
• Re-sanded shiny spots
• Re-tacked

3/30/12

Fairing, Day-1

The plan:

1. Apply multiple coats of resin, which will be allowed to cure to “green” stage between coats, to fill the fabric weave on half the 70-square foot surface only. This is to allow the material to be worked “green” into the night if necessary.
   
   
2. When the final fabric-filling coat has cured to “green” stage, apply epoxy thickened with West System 407 fairing filler to fill and fair low spots and other areas as necessary. Allow the fairing to cure overnight.

Today's work

10-10:45 a.m.

• Re-tacked with acetone cloth
• Rolled un-thickened epoxy on port half of top, fore and aft. Used foam 7-inch roller and random overlapping rolling pattern. Used 2-inch natural bristle disposable brush to tip surface for bubbles. Mixed 2:1 epoxy in 6-ounce batches. Used two batches with no waste to complete coat-1.
• Interrupted rolling frequently to attack any bubbles that appeared with tipping brush.
• Temperature in high 60s to low 70s.

This photo shows what it looked like after the first weave coat was rolled on and tipped. The glossy area is about the limit of my reach with my feet on the floor.

(You can click any picture to make it bigger).

1:30 p.m.

Surface still tacky. Temp high 70s. No bubbles apparent. It appears the weave is well filled and that the next application on this side will be fairing filler – after the epoxy has cured to a harder surface.

During the day, I refer often to West System Epoxy videos http://www.westsystem.com/ss/how-to-use-demos/ to make sure I am not forgetting some important detail.

3-4:45 p.m.

• Began fairing applications, mixing thickened epoxy to West System specs. The first pot was too thick. 

The back lighted photo at left should provide some idea of how much sanding awaits me in the morning. I have used the West System "micro-balloon" fillers before, but on much smaller projects. I think a lot of sanding will help me work out this mess .

• I mixed two additional  thickened epoxy pots, this time to a more syrupy than peanut-buttery consistency. This worked out much better, except the second pot  gelled unexpectedly on my last pass.

• The temperature hovered in the high seventies all afternoon. This no doubt reduced working times for the thickened mixtures.

This photo shows what the top looked like at the end of the day. I expect to start as early as I can in the morning so I can continue to work the epoxy before its fully-cured. This saves a lot of washing and sanding work that comes with letting the epoxy fully cure before the work is finished.



On deck tomorrow

Obviously, there is much more work left in this project. But I think I'm on a roll. I also think that the decision to do only half the top at a time was a good one. Today' work was manageable solo. I'll probably get the hang of it by the end of the day tomorrow.

And finally for today...

Please let me know if you think this is getting too technical and I'll try to simplify. On the other hand, if you want more detail, I can always elaborate. Use the comments box below. Thanks for following this story too.