I just glassed the bottom of my first surfboard. They made it look really easy on youtube.
I’ve got two problems.
When I got to sand the thick resin spots the resin heats up and clumps causing it to leave thick spots on my sand paper, therefore making my new sanding pad useless. I have to change them too often. (Using an oribital sander). Is there an industry trick to sanding these spots?
I didn’t wet the laps properly and alot of the rail has spots where the glass has lifted during the drying process. So I’m looking for advice. Should I sand it down to the foam and move on to glassing the top?
The resin dried faster then I thought so mistakes were made due to me panicking.
Polyester. I let it sit for 24 hours. I used about 1% Cataylst mix. The tempature was about 68 degrees. And by touch the resin wasn’t sticky. I thought it had it perfect.
try a sharp file rather than sandpaper on the clumps and bumps. Ideally you would use a Vixen file (see pic below, curved, very sharp teeth) but a 4-in-1 file (multiple sizes of teeth on the same metal file) will work too.
Awesome advice, thank you for the chemical breakdown I didn’t know any of that. I just mixed it with no wax and started soaking the foam. I’ll send pictures asap.
I had exactly the same happen to me on my 1st board. It’s a nightmare but now on my #2 build I’ve made such an improvement but still not easy getting the laps saturated and bubble free.
You’ll never forget that 1st lam.
Good luck and don’t let it put you off. It gets easier
…beware, do not use wax in the lamination; the wax (paraffin) is used in the hot and gloss coats only.
So you have 3 steps: lamination (stratification of the fibers to the core); the hot coat (the filler coat) and the finish coat (gloss coat; spray finish) This one is done after you sand the board (sand the hot coat)
so use a brush and saturate all the dry spots then open the bubbles, etc then laminate the deck and proceed with the other 2 steps.
Laminating resin has no wax in it, and it shouldn’t. Not sure what you mean by ‘soaking the foam’. The resin should be saturated into the glass after you lay your cloth on the blank. To get your laps and rails good and wet use a brush and your gloved hand. Pull the cloth away from the rail by hand and squish the resin in via the brush. Don’t press too hard with the brush. When it’s all soaked really well, a couple of light passes with a clean squeegee to smooth it out, lay it down proper, and pull excess resin out.
68 degrees working temp should not cause any issues if the catalyst ratio was correct. For dry spots, it depends how bad they are. Obvious bubbles or lifted areas should be cut or scraped away via whatever method you can. I use a short surform with a new blade. An alternative would be 36 grit floor sanding paper or a file as suggested previously. Files can cause shredding in the glass, though. Leaving loose random strands. If your paper is gumming up as you sand prior to lamming the other side, there’s some ways to correct it. Use a heavier grit and go really slow (hand sand, or low rpm on a grinder). Or, just baste the area to be sanded with a light coat of sanding resin. Once sanded, the next layer will bind.
The best people to ask about the mix ratios of your resin, catalyst, and surfacing agent are either:
The retailer that sold them-the one I use hands out a copy of the mix chart at time of purchase
The company that made them
The reason is that all polyester resins do not use the same percent of catalyst, the same as all epoxies** are not** 2 parts resin to 1 part hardener. You need the right chart for your sauce. Shop temperature and desired working time also can influence the amount of catalyst for polyester resin. Your supplier should be able to give tech advice on what they sell.
It’s even better if you have the MSDS (material safety data sheets) and TDS (technical data sheets) for anything stronger than water you intend on bringing into your workspace.
And when you get to using surfacing agents, realize that you can botch the job by overworking the applied resin which results in a sticky mess. Yep, done it wrong myself. Search and read threads on hot coats and gloss coats, and also the the stuff SammyA mentioned.
All the best, post back and tell us that you got it in the water, had a good surf, and are making plans for the next one.
Yes. Probably the #1 rookie mistake when it comes to hot coats. The surfacing agent is wax dissolved in styrene. Its sole function is to act as a barrier to air and allow a completely hard cure. Polyester resins are known as air inhibited type. Meaning they stay sticky when exposed to air. In a hot coat, the wax floats to the surface and forms a film/barrier. This lets the resin harden. If you brush your hot coat too much the wax film gets disturbed and you wind up with sticky spots. These are often visible as streaks that reflect light differently after the resin sets up. Be quick with your brushing, then leave it alone.
…hello man; it s simple: you walk away after your brush the resin lengthwise then crosswise then lengthwise again but without applying force.
The problems are: cold + humidity weather and/or to not have a heated controlled room. Have not enough SA in the resin (if you prepare your HC resin) or to have too much styrene and not so much paraffin.
Bad technique as SammyA mentioned.
So if you do not have any of that cases, you ll finish with a right Hot coat always.
