I’ve been having problems with the two boards I’m working on. I thought I’d start a separate thread to try and get some info or to hear others recount any issues they had with adhesion.
I’m making two “timberflex” boards. All seemed to be going well until I went to sand the laps and I noticed they were peeling up. I wasn’t about to strip off all the glass, so I kind just decided to go ahead and finish the boards. I sanded the lams with 150 before hoatcoating and wiped down with denatured alcohol. When I started sanding the hoat coat patches would just pop off like it was on wax paper. Again I peeled off the stuff that came off easlily, sanded like crazy, and put a second hot coat on. Yesterday I started working on the fins I laid up while lamming (or hotcoating, can’t remember), and the two layers of glass just peeled apart cleanly. WTF? Today,I was filling air bubbles/delam with a syringe and just the pressure of injecting resin was lifting off the glass. So I figure I got two disposable, mono use surfboards…
LIke they say at the end of the Coen Brothers movie “Burn After Reading”,
“Well, what did we learn from all this?”
“To never do that again!”
“Yeah, and I don’t know what the fuck we just did!”
It's almost impossible to figure this one out with real certainty without lab testing all your components, which is going to cost more than your two boards. Since it seemed to happen with each step (lam didn't stick to lam, hc didn't stick to lam, fin sheet etc.) it would seem to point to resin contamination/mix or an airborne contaminant in your lam room.
There's a lot of things that can go wrong when making a surfboard.
A simple test... try glassing some layers of the cloth together leaving little pull tabs at the ends.
Try it with fresh resin - epoxy and polyester just for kicks. See if you can pull the sheets apart after the resin cures.
If you want, send me a couple of pieces of the cloth and I'll do the same. I've yet to see any resin that couldn't hold a few pieces of glass together pretty good. I have some polyester resin, some Fiberglass Hawaii epoxy and some RR epoxy. I'll try them all and let you know what happens if you send me some cloth scraps.
Really a bummer to see these issues after all the work you put in to the shapes.
I just reread the original thread and something caught my eye... you wrote you sprayed the veneer softener. Was your cloth nearby?
Did you wipe with Denatured Alcohol everywhere you had adhesion issues? This is most likely your problem. After sanding blow off the surface and go for it. The guys that make the epoxies that I use whether its Resin Research, Greenroom or C3D will tell you not to wipe with Denatured Alcohol.
I have also recommended this about the alcohol wipe, the result of rapid evaporation is in a drop in temp. and the condensation of water vapor on the surface applied.
If you go back through the archives, everyone who has posted about chipping, peeling problems has wiped down with alcohol
I handle the laminations as very little as possible with my ungloved hands, always use some old #220 to scuff every thing before going to the next step, it makes a much flatter hotcoat and uses less resin too.
Thanks, for the replies. I always thought denatured alcohol was standard epoxy praxis. Guess I was misinformed. I reglassed an extra layer onto the back of the fins and used some glass from the lams and some really old scraps. No alcohol. Man, I was thinking of swearing off alcohol for my New Year’s resolution (a separate issue), now it looks like I have an easy out…“I meant the denatured alcohol I used when making surfboards.”
I have an eps/epoxy board that I am finishing. Before I did the bottom gloss coat I wiped the rails with alcohol. Then when I tried to tape it up the tape wouldn’t stick. First time that has happened. I had to get some 220 sandpaper and scuff it up to get the tape to stick. Weird.
Maybe the alcohol is the problem, my alcohol is old, and possibly contaminated.
On a side note, as a test I used a glossing epoxy from the hardware store and it was an interesting experience. The epoxy takes 8 hours to get to a non-tacky stage, and 72 hours to a full cure. The instructions say to use a gas torch to get the small air bubbles out. I didn’t do the torch part, but I used a squeegee and got most of the bubbles out and also was able to push the resin into what ever pin holes there were.
I must say that this was the nicest gloss finish I’ve seen. Problem is that the 8 hour wait is not good for the space that I work in, I got a few specks of dust in the finish.
Hey Shark, the torch could have been interesting- a new hollow surfboard building technique, melting the EPS and leaving a hollow shell…
I just sanded the resin dam for the tail and just the sanding pressure was creating new air bubbles.
I’m afraid the boards are a lost cause. I’m going to fin the bonzer, try both boards just to see how the shapes work, cry into my denatured alcohol and begin obsessing about my next build (which, after this fiasco, is going to be a harder sell to the better half, what with limited discretionary income and all).
Anybody have some personal board building disaster stories with which to console me?
PS- on a happier note, we finally got a decent swell and I’m on vacation and caught a few bombs. I was going to call it 2-4 Hawaiian with an occasional 5 footer, but I was studying the backs of the waves and the smaller ones I couldn’t catch (because I was too far out waiting for the biggies) had at least 6 foot backs. One guy was so happy he just kept saying, "I wait all year for this. Northwest swell. I live for this. I love it!’ I was thinking the same thing.
Lately, all my boards seem to have some problem. It’s usually during the glassing that I do something stupid or just don’t want to wait until I can use the right tools. Luckily, I’m riding all the boards, and they’re holding up. They just don’t look so good when you see them up close. There’s always something messed up somewhere. On the last board I finished, I wanted to get it done, so I hot coated it then the wind started blowing and I work in an open area. The board got coated with assortment of debris. Kind of like a tar and feather job. At least I could sand that down, but if you look carefully…
I broke my planer on the board I am currently working on so I had use a belt sander, disk sander/grinder, sanding blocks, block planes, surform, rasps, and cheese graters to finish shaping the board.
Regarding denatured alcohol... one of the issues Jeff had was layers of glass pulling apart when he did his fins. I assume no sanding or alcohol - just layers of glass and epoxy resin laminating the cloth all at once? I interpreted it as the layer of glass pulling apart from the other layer in a single stage lay up.
Disaster stories? The Brasington twins admit freely that they ''filled up dumpsters'' with rejects in the years they spent developing the Coil process. Pushing the limits has it's price.
My personal favorite disaster happened a long time ago (Jim Phillips will remember this one). I finished a brand-new board just in time to head for contest in Hatteras. Backed car over it and snapped it before I even waxed it. Much cursing and a detour by factory to repair, adding to 13 hr drive time....
I use 99% pure isopropyl alcohol that I buy at the local drug store or large grocery store…
On the bottle it has the percentage of alcohol which must be 99% pure for this type of use for this product…
Sitting right beside it on the store shelf is "rubbing " alcohol , which is 70% alcohol, 30% mineral oils…
Some rubbind alcohols are even mixed at lower (even) ratios… These different produts are sold /bottled by the same manufacturer…
If you use the wrong stuff the alcohol evaporates, and leaves behind a greasy film of mineral oil…
I wipe down boards, mix dye, thin dye/epoxy sealer coats., clean scissors/squeegees, etc…, with the 99% pure stuff, and I’ve absolutely never had a problem…
I used to use acetone for some of the tasks above,but I substituted isopropyl 5 years ago for the obvious safety / toxicity /cost reasons…
Perhaps rubbing alcohol was used by mistake, as this could surely cause problems similar to what’s going on here…
The only way you will find out what happened is to do some test panels with all the known variables accounted for. Denatured and Add F seem to be the most likely suspects. Least likely is cloth and resin/hardener but still a possibility.
I have never used Add f in my lams only my hotcoats. Have not had any adhesion problems between the two.
What epoxy did you buy and how old is it? Secondly, did you seal the blank? Thirdly, did you use plastic cups for mixing your resin from the supermarket as I think those can cause problems with epoxy?
As John Mellor said, the two layers of glass on my fin panel separated as cleanly as though there was a sheet of plastic between them. Obviously, no paint, no spackle, no alcohol. Alcohol is not the problem.
Like CJ, I don’t use add F in the lam (I’m too cheap). So the separation that occurred at the rail laps rules out the add F.
To answer Silly’s question- when I do timber boards I do free laps ( I don’t like to see the cut line and don’t want to do pinlines to cover them and cutting sems like an extra step). I just sand the edges and the “hangers”. Takes 5 minutes. When sanding the lap edges the laps started popping off. I sanded the laps when I realized there was a problem with adhesion, to “key” the surface and hopefully get a mechanical bond.
As far as mixing cups, they’re some cooking stuff I scavenged from my classroom at worfk (which use to be a Home Economics class). They’re wax coated paper so I suspected them but I used them on every board I’ve made. Never had issues. Not the cups.
Not the resin either, because I got the resin with AFOAF a couple of months ago and he’s had no issues.
When Mike Daniels mentioned the possibility of “airborne contaminants” I thought to myself, “Could my farts be that wicked???”