Hey guys.
Seen alot of people using uv cure poly resin. I use straight mekp as a hardner and was wondering…
Will using uv cure shorten the polyester resin smell since its hardening faster? Im thinking since the resin isnt wet, it will still smell but not as bad?
Just a thought…
It’s the same resin just different hardening agent. It does smell less.
Mako,
okay yeah always just wondered if it smelt less… with the remval of the MEKP, i was assuming it had to.
how much less would you say it smells compared to using the mekp
It is the chemical reaction that puts off the strong smell and noxious fumes. With UV the smell is essentially the same smell as uncatalyzed Poly resin. It’s not odorless and still requires a resirator, but isn’t anywhere near the same. Of course if it doesn’t smell like lavender or some other potpuorri(sp) it’ll offend most on this site.
Not only does the smell dissipate quicker (once you expose it to UV rays) but it also cures harder, faster so you don’t have to wait for a “full cure” to ride your board…not that any of us actually wait anyways:)
its fantastic stuff IMO, less smell when laminating and hardens to rideable in minutes.
Also whilst some boards seem to always have that “raw resin” smell, especially when warm, UV cured boards don’t. Even if there is MEKP in with the UVP.
I am not a chemist but I have some understanding of chemistry so I will probably make a mistake somewhere in this post. First of all, the smell in resin comes from styrene which is mixed in to thin the polyester resin down allowing it to flow. It is not from the linkage reaction. UV catalyst is dispersing in nature, in that it is blended throughout the resin in a more molecular way than MEK. You add the MEK and stir and hope it is evenly dispersed in the batch before it starts to gel. (Most of the sanding coat problems with poly brought up here on Sways are due to miss-mixed or under catalyzed batches).
By dispersing the catalyst in the resin and exposing it to UV, it causes an immediate linkage through the lam/hot coat, binding up the styrene and reducing the fume-off. UV boards do smell after laminations & hot coating, but the release is slow and over time. (Sniff some shop boards in the spring & you will see) A full linkage (cure) and out gassing of styrene occurs over about 2 weeks time.
From a safety & health standpoint, UV provides a limited exposure over time. High volume exposure over a short period is what most of the tests show is where the danger is. You will still need an appropriate molecular respirator to apply the resin. I use UV for repairs because it allows me to sand in an appropriate time frame, and if I were doing my own glassing (which I could do but don’t want anymore exposure than I already have) I would only use UV for poly.
I am lucky that I don’t have any problems from the exposure I had back in the day. We lamed, hot coated, etc. with a cigarette in our mouths and sometimes walked in circles in the parking lot before driving home for the day! Just my 2c….
Hi hansel -
Surfteach is correct.
I’ve used both (MEKP and UV powder catalyst) and believe me, the smell is still noticeable with powdered UV catalyst. I spread a plastic drop cloth in the garage and make sure I take it out in the sun while the board is curing just to make sure I don’t have some unkicked resin sitting there on the floor spewing styrene fumes. IT STILL STINKS.
And it is the styrene evaporating that gives off the main odor. Anybody not involved with fiberglassing seems to find it offensive. My girlfriend and the neighbors notice immediately if I’ve been glassing with poly in the garage. I was in a bicycle shop the other day and one of the shop guys noticed a “resin smell” and I hadn’t even been glassing. Maybe it was coming from one of the other units in the industrial complex? (I couldn’t smell it.)
Nobody seems to notice though when I use epoxy. Even with an attached garage, nobody notices the smell when they enter the house.
I remember doing quick poly gloss resin jobs before school back in the day and the smell from just a couple of drops on the bottom of my shoes would be identified by people sitting near me. Or maybe it was just my B.O. - I just noticed that the Google ads are popping up with ‘AXE’ deoderant.
If you’re really interested in cutting back on the smell, try epoxy.