sgt. slick said:
Being my first time, does anyone have any input before I start laying down the fiberglass, any thing you learned from doing yours or just any steps you feel I left out. Sorry for the poor pictures. My camera broke an had to use my cell phone to take the pics. I know the images are side ways i just posted them so that you can get a visual of each step.
My first time, I way over did it with the resin. After the resin kicks, each layer should be dull; if you have shiny, "slick" looking spots you used a bit too much resin.You want just enough to saturate the fibers without any excess resin above or below each layer. More than 90% of the strength in fiberglass comes from the fibers, the resin is designed to hold the fibers where you lay them and to bond each layer to the last. For a seat, I'd recommend you find a composite shop in your area and pick up some "impact resin" so your weight and road bumps don't crack the pan over time. If you can't find it, don't worry any poly or epoxy resin will work but don't skimp on the number of layers and overall thickness of the part.
As you lay up the fiber, use cheap disposable brushes, you can clean these with lacquer thinner or acetone and reuse them if you'd like. Dab small sections at a time, start from the highest point of your mold and work your way down and out; this method pushes excess fibers to the bottom where they can be trimmed and helps minimize bubbles.
If you get bubbles, try to dab them over to an edge with your brush. A $10 fiberglass roller works well for this also. Some bubbles are hard to get rid of and you may miss some. After the resin starts to kick, it will gel up. Before it hardens completely, you can cut the bubble open with a sharp razor and dab resin into the opening.
Before you lay each successive layer, scan the surface of the part for any fibers or spots of hardened resin that stand off the surface more than a mm or so. You may want to grind these down with some 80 or 60 grit sand paper as they are more than likely to cause bubbles in the next layer.
Make sure the room you're working in is an absolute 60 degrees Fahrenheit minimum or your resin won't cure. Preferably, lay up in 65 to 70 degrees. The hotter it is, the quicker your resin will kick, so if it's too hot, you won't have much working time. Also, many store-bought brands of resin recommend 14 drops of hardener per ounce, this is the maximum ratio and I wouldn't advise you use this much hardener. If you're taking your time to lay up a smooth layer with no bubbles, you'll be lucky to get 2 or 3 ounces on your part before it starts gelling with that mixture. I typically mix ten drops per ounce and lay up 4 or 5 ounces per mix and get 10-15 minutes before it kicks. My conditions are different than yours will be, you'll just have to play with it. If you're resin starts to gel in the bottom of your cut bucket before you get a chance to lay it up, either mix less resin by volume the next time or use less hardener.
I hope this is helpful. Fiberglass is time-consuming stuff but it's super dynamic and can create attractive, high-quality parts. Be sure to post up your progress.
Josch
