I need some quick advice. Bought some lam resin yesterday and just now poured it out to use it. Looks a lot darker than I’m used to. The resin I’ve bought in the past was aqua blue. The resin I just poured out looks much darker. It’s blue/green with a heavy grey cast. It flowed good and the can doesn’t have any rust or crystalized resin but it’s way darker and that worries me.
Is this the normal color of some lam resins? I’ll try to get a pic up soon. I needed to get this thread up ASAP because I’m in the middle of the project. Haven’t catalyzed it yet.
I appreciate any help.
EDIT
Okay here’s a pic. On the left is what I’m used to. On the right is the stuff that’s got me nervous. Should I just take it back and thank the guys for screwing up my Saturday project, or is this normal for some resins?
I don’t know if it’s necessarily bad resin. Ddi it harden up OK? I used to work at a boat builder and the resin we used was dark green like that and turned brownish. It might be what is known as isophthalic polyester resin, which is actually stronger than normal surfboard laminating resin which is orthophthalic (any other experts out there can correct me if I’m wrong). Of course boats get painted so the aesthetic aspect is not a consideration.
Howzit Ryan, Looks kind of like the resin we used to make molds. I would take it back and ask them what’s up,I think they sold you the wrong resin since it’s definitely not for surfboards.Some people working at material stores don’t have a clue as to what they are selling.Aloha,Kokua
Yah, it seemed to harden okay. A little slower than I would’ve expected. 18 drops/oz should kick regular lam pretty quick. Took this about 20 minutes to gel but it’s hard as rock now. The brown is about the color of iced tea. Sounds like you might have the right call on this one. The place I bought it from also supplies boat work which makes for a good chance to screw-up.
The side of the can has check boxes for C.Lam and B. Lam. B. Lam is checked on my can. Never heard of C. or B. Lam before. The guy knew I was doing board work. Oh well, a little time and a wasted drive is what I’ve lost. Not nearly as bad as if I would’ve done the lam. I’ll take it back to the shop this week and get the right stuff. I’m a little pissed because I’ve got to drive back there and I didn’t get done what I had planned.
I accidentally bought some of the same stuff, but I went ahead and used it anyway because it was all I had at the time and I thought “What the heck, I’ll give it a try”. It was actually the boat resin mentioned before.
Funny thing was, once it was spread out on the board, it didn’t look dark anymore since it was so thin. It’s mostly a white board with some colored stripes. The white looks white. It’s 6 years old and is still in use. Holding up fine.
Howzit Ryan, C. resin could mean Casting resin. Also if it's boat resin it should not be tacky like surfboard lam resin, boat resin can be sanded after it kicks off.Aloha,Kokua
when Aido [‘AJ72’] and I went to my surfboard supplies guy [? last week?] , he mentioned the [silmar] laminating resin was now a slightly different colour than before .
[from memory , more greenish …it used to be a very bluish colour]
I wonder if the same thing as mentioned …once it is spread out thin , no noticeable colour casts on a white board ?
perhaps when I eventually buy some , I will test it on some scrap foam first , I think …
Howzit chip, UV resin has a greenish color to it after the UV catalyst powder is added. Before adding UV catalyst the resin is a blueish color.Aloha,Kokua
I don’t know if it’s necessarily bad resin. Ddi it harden up OK? I used to work at a boat builder and the resin we used was dark green like that and turned brownish. It might be what is known as isophthalic polyester resin, which is actually stronger than normal surfboard laminating resin which is orthophthalic (any other experts out there can correct me if I’m wrong). Of course boats get painted so the aesthetic aspect is not a consideration.
I’m no resin expert either, but I’m pretty sure that all QUALITY resins used specifically for surfboards are isophtalics. I don’t know whether they are stronger or not than orthophtalics, but they are much less water-permeable. Hence their use for boats, surfboards, swimming-pools…
you are both right - surfboard resing and boat building resing are isophthalic polyester’s.
The difference being that surfbaord resing is processed to cure clear and has a UV stabalising additive, some companies also add a rubberising agent to make the resin slightly more flexible so it doesnt crack as easily (but will probably “ding” slightly easier)
The major difference is in colour/clarity and the fact that a standard isophthalic will go slighty yellow with age and sunlight.
I glassed my first longboard in standard iso for this exact reason as I wanted that 60’s yellow glass effect… old school…
I think you’ve already figured this one out, but it looks like the gel coat used for boat building, as it gets painted no worries about the colour, brown/orrange to pink.
If possible take your samples to them to help explain, or e-mail them the pics.
Once I was sold wax solution in a container marked as catylist, glad I trusted my instincs and didn’t go a head and use it.
No need for all that muck. I’ll be in their shop during my lunch today. But yah, I think you’re right. With the help of the guys here, it looks like they gave me boat resin.
They were trying to figure out the price difference and how to charge me the 50 cents or whatever it was. I said “C’mon, you’re gonna charge me and I had to drive down here twice”. They looked at me confused. Anyway they didn’t charge me the difference but made sure to let me know it can be confusing and I need to specify what I’m using it for.
Let’s see, I’m buying 4 oz. cloth, lam resin, gloss resin (not for boats), mixing cups, and asking about poly tints being used with epoxy, and I’m supposed to know that they have different Lam resins. I’ve been in there a half dozen times and never had to specify anything. I suppose they asked me what I was using it for the other times. When I bought it this time, there were two guys working and me and one other customer in the store. Not exactly a super busy.
Sheesh! You’d think when a customer asks for Laminating Resin, the counter guy might ask “What kind?”, and then I might say “What do you mean what kind? Are there different kinds?” and then we’d have more conversation that prevents this from happening. Not rocket science. Here guys, let me help you help me. I mean why did the guy give me anything if all I said was Lam resin.
All right. I’ve vented. They’re farther away than the other guy but they had the wider cloth that I needed. I’ll be back because they’ve got stuff I can get elsewhere.
I know what you mean… I used to work in the composites industry and to the uninitiated there is a whole range of product out there that is made with a specific purpose in mind and then there are others that are used for anything and the lines are often blurred by what people actually do with them.
There are hundreds of different resins for different jobs - fire retardant, chemical resistance, impact, torsional stress and even electro magnectic conductivity just to scratch the surface… just like there are hundres for different fibre blends and weaves (twill, crows foot, 3d knits, biaxial, triaxial etc. etc)
Its all good though - building a surfboard is pretty hard to get wrong even with the most basic of materials.
I recently saw a board for sale in a vintage board collectors store at Kirra that was “glassed” with GP Iso (general purpose Isophthalic - the brownish stuff) and fly screen!!!
it had a big label saying “the poor mans glass job - 1967” If that thing has survived all these years and looked pretty good (well… all things considered) then Im sure your board will be great.
even “not quite right” can turn out to be a blast!
even with the most basic of materials.