Epoxy resin recommendatione

Kan, a squeegee was a game changer for me. I went to a boat suppy store. Got like a 5 pack for cheap.

Before buying those i would of used those hard plastic cards.... you know like a old gift card or somthing.

 

Go to Harbor Freight, they have a good selection of sizes and thicknesses.

 

Resin research is really good quality but most of the good epoxy resins are 3 times the cost of polyester resins like silmar,the fumes from any type of polyester resin are pretty dangerous to your health,if yu use it yu should do it outside ,if yu cant do it outside dont do it inside your garage use someone elses garage .so just for health reasons alone epoxy is way mo betta for folks doing own repairs and builds ,as for the bubbles in resin it is different than poly yu have to move a bit slower or it will get some bubbles in it ,the add F is a must

 

fish eyes in epoxy hot coats have given my FITS. its not a big deal on a small ding repair, you can just fill them in with dabs and sand it flat. Having fish eyes in a large ding repair hotcoat like a section reglass, or worse yet a new board is a huge pain in the ass. I wish i knew for sure how to avoid them, but it still happens so i know i'm missing something. Here are some things i suspect can lead to epoxy hotcoat fish eyes (holes):

hoatcoating with epoxy in high summer humidity...the board could be damp.

hotcoating with epoxy a board or brush or on a rack that has come in contact with wax, oils, oil-based paints, hand oils or perspiration, handling the board with bare hands. use a clean rag or paper towels.

grit like sanding residue, fiberglass particles, dust, etc.

blowing a board clean with an air compressor that has oil residue or condensation in the tank so basically as you blow the board clean you are coating in with spray that had fish-eye forming junk in the air stream.

Lastly, using epoxy resin with a slow hardener. I try to get epoxy resin as warm and runny as possible for hoatcoating with a fast hardener, and wait a few minutes stirring off and on so it will be getting ready to set up when i stop the brushing. Time spent with the epoxy resin sitting on the board in a liquid state is your enemy.

 

this would be a really bad case...but I've accidentally set a board on a rack with surf wax on it then hotcoated, or had epoxy react badly with a paint application underneath and had a patch look just like this. its almost as if the resin is being"repelled" from the contamination and piles up as it moves away from the contaminant - i might be wrong about the physics but this is exactly what a bad case looks like

 

There are a lot of pitfalls and down sides to building boards with epoxy resin. It is much more sensitive to environmental conditions, hand prints, dust, temperature and on and on. Its more costly, takes longer to complete a board and a pain to sand. You really have to have the right workspace to do the job right and you need to be a meticulous person with it. I built a number of boards with epoxy a decade ago then switched back to poly. The epoxies available back then were not nearly as UV stable as what's out there now. I had a batch of boards yellow pretty bad within 6 months and I was over it with epoxy. The epoxies have improved a bit since then but still aren't good enough to draw me back. Using poly I've already shaped, glassed, sanded and finished a board in less than 48 hours start to finish. To me the speed factor of poly is really hard to beat.

 

Regarding fisheyes in hotcoats... Grit, dust, dog hairs, brush hairs, etc... don't cause fisheyes; they cause zits, which are easily sanded out. You want keep things clean to avoid them, but at least they're relatively easy to deal with.

Fisheyes are from contamination or residues. Contamination in the brush or bucket, or residues from wax, oils, grease, etc. The key to avoiding fisheyes to to keep everything clean and/or new. I use a new plastic bucket, or a bucket that has only had fully cured resin in it that I can pop out and get back to clean plastic. Under no circumstances do I EVER reuse a brush for hotcoating epoxy. A new, 4-inch natural bristle brush only. If you're bucket, brush and stick are clean, the only thing left is the board...

Freshly sanded board, not put on any other rack except the glassing rack. I have another 4-inch brush that I use to brush off the sanded board, and when I tape off the rail to get a drip edge, I use gloved hands. I do not run tape all over the board to pick up dust... you can do that for poly gloss coats, but never epoxy. After sweeping off the board with a brush, any remaining particles of sanding dust will be minute, and disburse into the hotcoat. I used to use a clean, new shop towel and do a denatured alcohol wipe before hotcoating, but I found it wasn't necessary if you never contaminated the surface of the board with anything to begin with. If you're not sure... do the alcohol wipe; better safe than sorry. Follow with a clean sweep with the brush to remove any towel fibers.

Last tip for hotcoating epoxy... Take a clean piece of 80 grit on a soft block, and scratch the lam up good. I go nose to tail, rail to rail, then diagonal at opposing angles. This will give more tooth to the lamination for the hotcoat to grab onto, help remove any surface contamination (if there is any), and remove any surface agent (Add F) that rose to the surface before the lam cured. You're not "sanding" the lam... just scratching the surface to get a better mechanical bond. A clean, scratched up surface assures you will never get a single fisheye... ever.

 

My process is pretty much same as lb uses ,especially keeping oils, dirt ,junk from your hands off the board while yu shape , ive seen boards where yu could see the hand prints in foam along rails cuz just flippin it over on your stand can leave them , i never reuse brushes ,the cleaner yu keep it the better the result,the temps in area your glassing in have to be right. I have used poly for decades ,epoxy was complete crap yellowed out,cracked and got ugly,but the RR epoxy resin now with the optical clarifiers and all its pretty good stuff. The days of huffing all that poly are done for me i try to avoid using it unless its a restore job on a vintage board . But yu still dont want to just fill holes with resin of any kind .

 

Yu need to get the heavy duty nitrile gloves from HF they are pretty cheap latex wont hold up worth a damn

 

^^^Yup... I've had cheap latex gloves turn yellow on contact with epoxy... then everything you touch leaves a yellow stain. Nitrile is definitely best.