today i attempted my first lam. i got a 5 gallon drum of lam resin and enough UV catalyst for the 5 gallons. when i started today i filled my first bucket with resin. i initially thought that bucket was a quart, but i now am realizing that it was the 2 quart bucket. anyways, i nearly filled the bucket with resin. then, not knowing exactly the exact amount, i decided to eyeball the amount of catalyst needed for the resin. i put in about a tablespoon which might have been right for the 1 quart tha ti thought it was. i then mixed the catalyst thorougly and divided into two smaller buckets where i added my pigments. i then did my lam. it seemed like i put on a lot of resin, i went through a littel mroe than a quart. when i had finished everything, i set the board up outside in the sun. after like 2 and a half hours, it is still tacky. suggestions or input? for reference, this board is 6’0" with one sheet of 6oz cloth on the bottom. thanks.
“Tacky” is OK for a lam coat. That’s the way it should be, in order for the hot-coat to adhere to it. What’s not OK is if your resin is still “flowing”. Check the leftover resin in your buckets: how does it look like? Flowing, you have a problem. A solid piece of plastic in the bottom of the bucket, everything is OK. In case it’s still flowing, I’d suggest doing a strongly catalysed hot coat to make the lam-coat go off.
Sounds fine, lam resin should be “tacky” and will only go hard once the hot coat is applied, if you are worried obout this happening in the future try adding a very small ammount of regular Menkept catalyst to the batch as well, then even if the uv is not working is will still kick eventually.
Woody,
from what I read in Skinnyhb’s message, I assumed he had been using regular thermo-setting resin, not UV-setting resin, since he actually put “a tablespoon” of mekp in it. In which case, anyway, putting the board in the sun doesn’t sound like a great idea. (I got bubbles every time I did that…) So, Skinnyhb, what kind of resin was it?
ya, it was a UV setting resin. and i checked it again last night and it doesn’t seem to be all that bad, although it did bubble up in spots, i think i can remedy that.
The way I read it, he added a tablespoon of the UV catalyst powder? I buy mine pre-mixed but if I was gonna mix my own I’d stick to some easy to figure proportions. Not sure how much powder is provided for 5 gallons - if you weighed or measured it and divided by 5 you’d know exactly how much to add to one gallon. Also, what’s left in the bucket won’t kick until you’ve put it in the sun. What about the pigment? Is it super opaque? That’ll keep it from kicking properly too.
Howzit John, What I don't understand is why he didn't just add all the UV catalyst powder to the 5 gal bucket in the first place. That's what I would do and then roll the bucket around the yard for about 10 minutes to get a good mix. Fiberglass HI messed up one of my orders and had to send me the proper amount of powder for 5gals, it was 2 ozs for 5 gals. Aloha,Kokua
i got a 5 gallon drum of lam resin and enough UV catalyst for the 5 gallons.
I’m sorry. I should have read better. “UV catalyst”. Not MEKP. Sorry again.
Buy yourself some cheap 2 quart paint buckets at the hardware store, They have the measurments marked on there. $1.00 ea.
I use large PP messuring jugs (90 fld oz) the common kitchen varierty, the thing I like about these is I have to deal with both metric and imperial scales and these have all dif types of messurements on, not sure how large that is in quarts or gallons though, not measurements I’m used to using.
When mixing the resin I transfer a bit at a time into another bucket, mixing in a little cat at a time then when its all transfered i give it a final mix.
Woody:
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check the resin in the bucket, it it’s hard you’re okay.
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Adding extra catalyst to the hot coat resin WILL NOT do anything - not a damn thing - to change the lam resin already applied, once the lam resin has set. Once set, the lam resin just won’t allow the molecules of catalyst to sufficiently “penetrate” or “mix” to do any good. Some on this board seem to think it can, but no; it’s wishful thinking. When you’re setting off a chemical reaction that you can’t reverse, you gotta think and think again.
This is not to say I didn’t once brush out a hot coat without catalyst - I did. But I gathered the resin back into the bucket as best I could, added some to make up the batch I needed, catalyzed and re-spread. It came out okay. But that was with liquid resin. If it had gelled, I’d have been up the proverbial passageway with no possible means of propulsion.
IFFFF the lam is sticky, not just tacky, and the bucket resin confirms this, OR if you have any doubt whether the lam is sufficiently cured, I’d put it in direct sun till it gets nice and warm, or longer. Heat will help the resin go off; the UV would assist in the resin setting also. I have never had a problem with sunlight, except normally catalyzed jobs don’t need it; don’t let a rain sneak in on you; UV hot coats and finish coats (with surfacing agent added) should sit in relatively low light for say 10 to 15 minutes so the wax can rise, then out to sunlight or turn on the UV light.