I have about 2-3L of UV catalysed resin left in the bottom of a 20L bucket, and about the same in uncatalysed resin from a separate batch sitting on the shelf. Do you think if I mixed say, half the uncatalysed resin with the UV gear, that it would still go off in the sun? I’m trying to get my next board glassed without having to order a whole new batch of resin, which will cost upwards of $200 once you factor in shipping.
If it were me I would use one lot of resin (say your UV) to do the lam and then the rest catalysed with MEKP for the hotcoat. That way you use it all and dont have the potential problems for error.
I agree with tommorth and thirdshade, both great advice. If you have to “stretch” your resin like you are saying and you do have equal parts, 2 L UV and 2 L regular, you could mix the two together and it will eventually kick. However, I don’t recommend it because you’ll run into some issue, such as the resin draining, and debris landing on your board while it sits waiting to cure. I’d suggest ordering some UV powder that you could add to your resin. We sell it in 1 gallon up to 55 gallon sizes. Good luck.
Thanks for the responses. I’ve got some MEKP, so no problems there. It’s just that glassing with UV is so much easier for a novice like me. There’s less pressure to get it done within a certain timeframe, whereas with MEKP you only have a limited time to get it done, or else you’re fucked.
Mind you, it’s a skill I should probably learn at some stage (and I should stop being such a tightarse - it’s only money, after all). Man up Cass!
While I’m on the subject; what ratio would you use for a hotcoat (%MEKP), as opposed to laminating? Would they be different, or the same?
Tommorth - I’m glassing a little number I’m calling it the Bastard Fish - 6’ x 20" (15" at tail and nose) x 2.5ish. I’d post a photo, but “computer says no”. It’ll be my go-to board for the 2-3 foot beachbreaks we mostly get over here in the Adelaide region. I think I may have posted pictures somewhere else recently…
Hey fiberglasshi, I would order some sort of UV agent, but I want to glass this f**ker on Friday, and my supplies have to come all the way from the east coast, which takes at least a week and a half (even longer while the Quiksilver Pro is on at the Goldy - “Gone Surfing” signs on all the businesses over there at the moment).
"Thanks for the responses. I've got some MEKP, so no problems there. It's just that glassing with UV is so much easier for a novice like me. There's less pressure to get it done within a certain timeframe, whereas with MEKP you only have a limited time to get it done, or else you're fucked"
I get it............but you are only "fucked" by not having a proper mix.
I'm almost 100% epoxy now...but.....my friend in San Diego does excellent poly glass work.....and he takes his time...no stress.....my friend can do them fast but I see 20 min lam jobs all the time...sometimes longer...you can lay up a board in 20....right? .......maybe you need a helper.......I do longboards with no help...but when my buddy Mark helps....it takes away alot of stress...................
Yeah, the 2L should be fine for laminating. I was trying to stretch it out to cover the hotcoat too, but I think that will have to be done with the MEKP.
20 Minutes shouldn’t be a problem Ray. It’s only my 7th board, but while I’m a long way from what I’d consider competent, I’m not a complete nuby. What sort of ratio would your mate use to aim for a 20-minute lam? I was thinking something in the range of 1-1.5%?
C’mon guys, I know it’s a bit of a rookie question, but I’m going to be glassing tomorrow and would very much like to not fuck it up by adding too much/not enough MEKP. What’s the sweet spot for mixing it so I’ll have at least 15 minutes to play with when laminating a 6ft board?
BTW - it’s forecast to be about 33-34C (93.2F) tomorrow, so I’m going to try to get it done mid-late morning, to avoid being stuck in a hot tin shed for the afternoon.
Do you have the supplier’s mix chart or manufacturer’s technical data sheet on your resin? One of those should give you the baseline % of MEKP plus a working time at a given temp. My lam and gloss resin each took different amounts. With the heat I don’t think you would want to add extra MEKP.
I hope it goes well, I really like the stripes on your profile pic.
Hi cass, I would use a little under 1% or it’s going to kick pretty quick over there in your summer heat. There’s a risk of slowly catalysed resin draining into the blank, leaving your lam dry but I guess it’s pretty warm over there so you won’t have that problem. If you go as low as 0.8% you should be fine.
Cheers
Rich Www.thirdshade.com
No worries. We send containers over monthly and we ship out daily so I’m sure we can get you what you need sooner than later next time. Good luck and let me know how it works out!
I'm not clear on how you are mixing your UV cure with conventional but at 90 degrees+ you don't want to mix it too hot and you don't want to accelerate the cure rate further by UV exposure. I think it was Kokua who once posted that his UV resin seemed to kick faster than conventional resin when he used MEKP with it... with no UV exposure.
HERE is a link to a catalyst chart. Stick to the light side (1% or less) of MEKP proportions... with UV resin a bit less than the smallest amount recommended in the chart. Just remember you have two things already acting as accelerators - heat and premixed UV catalyst.
Yew! Awesome, thanks everyone for the advice and JM, thanks for the link. I’ll go carefully and hopefully will be one step closer to finally having a board that suits the waves I’ve been surfing for the past 7 years.
Yeah, the 2L should be fine for laminating. I was trying to stretch it out to cover the hotcoat too, but I think that will have to be done with the MEKP.
20 Minutes shouldn't be a problem Ray. It's only my 7th board, but while I'm a long way from what I'd consider competent, I'm not a complete nuby. What sort of ratio would your mate use to aim for a 20-minute lam? I was thinking something in the range of 1-1.5%?
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The number One reason I switched from Poly to Epoxy is the smell.....or lack of smell....low VOC.
The number two reason is that RR Epoxy is always a 2:1 mix....no matter what......no 1.5% or other half baked guesses due to temp or humidity or spin of the earth.......There's plenty of charts out there for you.....a 20 min lam is possible.
A proper batch will yeild a proper lam.....I'm done with poly...I only use it for repairs now...