hello swaylockians- this is a copy of a message i sent to greg loehr concerning his rr epoxy. i tried it for the first time this weekend. i know some of you are using the stuff, and ive scoured the archives, but im looking for some suggestions or possible solutions. if any of you could help, id appreciate it. does anyone have any experience using this stuff in colder climates where 70 degrees is a luxury in a house, let alone a glassing shed? im freezing my ass off up here in new york. anyway, i attempted to test glass a handboard this weekend and it turned into a gummy, flexy mess. now, im trying to be as anal as i can about the mix ratio and temp, but being a backyard/basement type of guy, its a little tough. here is what i did: 1) i have two large glass beakers and 1 10ml graduated cylinder courtesy of my school district (they are my “sponsor”) 2) i measured the resin in one beaker, and the hardner in the other. exactly half. 3) i then measured the additive f in the graduated cylinder, making sure i had 1ml per ounce of resin/hardner mix 4) i poured all three into the a paper bucket, mixed for about 4 minutes straight, and then poured the mix onto the board 5) let the mix sit on the flats until saturated, then spread over the laps & tucked. results- two days later, its crystal clear, but i can still put a finger print in it these are my thoughts on possible problems: -temperature: i did all this in a basement (unventilated, with a mask- girlfriend not happy) and the temp was in the low 60’s----is this too cold? -mix procedure: i read a post on the sway about the leftover resin in the measuring container causing problems—this makes sense, but how do i avoid it? mix everyting in one container? i havent found a disposable bucket that would be accurate enough & i cant keep using the beakers. ok- so what are your thoughts? im thinking that i need to make a heat box out of insulation board, but im not sure if i need to glass in there, or if i could glass in cooler temps, and then let it cure in the box? would this change in temp lead to off gassing? once again, thanks again for allowing me to pester you with my ignorance john
John: I’ve only used Greg’s R/R products for 6 or 7 boards so my experience is limited. First let’s clarify your mixing ratios, 2 parts epoxy resin to 1 part hardener. Right? Another way I’ve tried to solve the sub-70 degree temp problems is to use an ice chest with my 2 plastic epoxy jugs sitting down inside. Next I take a Salvation Army $2.99 water bed heater and toss it down inside around the jugs set at 70 degrees +/-. Doesn’t take long inside the cooler to improve the viscosity. (my last lamination batch, resin/hardener/Add F, I used Plus One Shaper’s method of 15 seconds on high setting in an old microwave, it worked great! Free flowing and no adverse curing effects) For mixing I use the one quart plastic graduates that almost any ACE Hardware or lumber yard carries in the paint isle. They are milky clear plastic with green graduation marks. Perfect for measuring mixes for a 6’ board on up to a 9’6". I reuse these many times over. I NEVER use any container that has had Polyester resin in it. Not sure why your batch is still soft unless it was contaminated or the wrong mix ratio. Tom S.
tom- thanks for the tip on preheating the resin/hardner/add f mix- you mentioned that you have battled the temperature as well- do you glass in a cool environment and then cure someplace warmer? thanks
I always save the left over resin to check the cure. Is your left over hard or gooie?
Hey John O If You’re gonna use one container try using a scale and work out Your ratios by weight not volume. Works great and You can use any old container for mixing. I’ve used well washed and dried out old milk cartons (Tetra pak) Good Luck p.s I’m no expert on the subject
phil- thanks for the response- i actually saved a few small (dixie cup) containers of the batch- i kept one in the basement (to keep same temp), one in the living room (aprox 70 degrees), and i placed one in an oven that started at approx 100 degrees and cooled to room temp. im still in the process of testing these for a full cure, but it seems as though they are still going to be gummy. im a science teacher & well versed in the scientific method; im trying not to butcher the process, but i think im getting desperate. any application or curing suggestions? thanks
Oh yeah another thing if You decide to measure by weight. The mix ratio might be slightly different if You measure by weight instead of by volume, make sure You check Your epoxy sytems product sheet. I use Epoxy from Spsystems in the UK, this is what it says on the manual for it:Mix Ratio (by weight) 100 33.3 Mix Ratio (by volume) 100 40 Well just an example for You, the first figures are for the Resin and 2nd for the hardener
as if i havent asked enough questions: has anyone using additive f come up with a good way not to spill that stuff? im pouring from the metal pint containers (look like acetone/thinner containers) and i believed ive quenched the floors thirst for it.
I have often done laminations when the temperature is around 55 degree with R.R. epoxy. When it get colder than this the material doesn’t flow well so I find this to be the lower temperature limit that I’m will to venture a lamination in. Once the cloth is wetted out well and I want the lamination to cure. I simple hang a 60-watt incandescent bulb with a larger bell shaped reflector over it about 6 inches for the surface of the lamination. This will very gradually and gently warm the resin clear through and make it cure very nicely. A panel of lights such as this placed over the lamination with a white reflecting panel over it will accelerate curing time when temperatures dip to as low as the high 30’s. If the resin is mixed in the wrong proportions you have an irreversible mistake on your hands. Mahalo, Rich
Limited personal experience here… I’ve read that if you use the same measuring container that even what’s left over from the part 1 and stuck to the sides will affect the amount you measure of part 2 (i.e. a little too much part 1 and a little too little of part 2) Scraping the sides and bottom of the mixing container will enhance total mix. System Three has a pretty nice website with various tips, pointers and FAQs. Here’s a sample… Q: I made a small batch and after a week it has not cured. What happened? A: It is difficult to measure a batch of resin and hardener less than three fluid ounces by volume. If you need to make a small batch, measure it by weight. System Three offers a small digital scale perfect for this use. Also, please don’t think that this is the same or better than Greg Loehr’s product. Greg has been very responsive to everybody’s questions and has delivered good product and great back up. Several people have had good success with his stuff. Consider the link an adjunct to his info. http://www.systemthree.com/index_2.asp
I can identify two areas of concern. First, if your epoxy batch is thick to stir, then you are having a certain degree (no pun intended) of temperature issues. What you do about it will obviously vary and like Tom Sterne says preheating will really help working viscosity; if you have a microwave to spare (not for food use) then I suggest “nuking” your batch. DO NOT exceed 20 seconds on high power, as most polymers will heat much quicker than water. Your goal here is not to exceed 90F. This is assuming a small batch for a board bottom 9-12oz total. The second thing has been a huge benefit in our factory (with temps as low as 55F) and that is post curing. We have an oven in our place (10ft tall x 10ft long x 2ft wide). In the above situation, I can have a side lammed and dry to the touch in about 45 minutes!!! We’ve built boards from shaped blank to ready to ride in a single work day. Please hear me out, the oven can be down-scaled for a single board. I explained this a couple of months ago. Basically, you build a foam box around your board after you glass it. A space heater (oil filled safety type preferred) is placed on the floor in the box. The heat rises into the upper portion of the box where the board is and the post curing takes place. Greg told me that 24 hours at 125 degrees gives me a full cure (two weeks at room temp). The box is made of the foam insulation sheets from home improvement centers/hardware stores. Some ingenious contributor suggested that skewer rods could be used to hold the box together. The latest version of the “curing box” has the space heater well exposed and away from any foam structures (chopped away for safety and for quick inspection). That heater should not be set on “burn the house down” mode and one must not go and “take in a movie” only to come “home” to clean-up/fire crews. If you use a heater in the house or space heat a room then you are utilizing the same concept. Heck, if you’ve got the dough, just heat the whole room to 78F and the lam will be touchable (albiet, not as cured) in a decent amount of time; the room is a “cure box”. Another suggestion was to stab a candy thermometer up near (not through) the board so your heater settings can be optimized. Inspect regularly for the hour or so it takes to cure the lamination. One last note on mixing. Try using a common container that will accumulate the resin, hardener, and F. The reason is to cover yourself for any losses due to transfer of material. You’d be surprised on the amount of material can be “hidden” as film on the measuring container; try playing with the containers the resin comes in to see an example. So, use graduated cylinders to measure some water to say, 3oz and pour it into a clear plastic container; make a mark (tape, pen, etc.) Do this for 6oz, 9oz, 12oz etc. The clear plastic container becomes the only thing you will be pouring the actual materials. Okay, finally here’s a tip on the additive F, I found it to be pretty “loose” with respect to measurement; that is, you can be off a little and it won’t kill your project. Knowing this, I found Greg’s pint cans have a lid that holds about 10ml/10cc so for every oz of HARDENER add 1ml of F (hey, that’s metric to standard). For a 9oz batch I use just about 1/3 of a capful. Hope Greg doesn’t kill me on that one, AND he doesn’t change the additive F containers any time soon. Anyways, hope this helps; sorry for so many words. Good Luck. PS. small batches can be done using a tall cylindrically shaped container (such as a drinking straw that is calibrated with marks) and using a pipette drawing technique (get someone else to do it, j.k.) Squeeze the measured contents of each straw onto a flat surface and “smear” to mix the batch.
I’ve had epoxy that cured to a very flexible state. Not gummy to the point where you’d see your fingerprint in it, but it seemed much more flexible than it should. Someone mentioned mixing in one container and using weight, I think that helps alot. Due to the viscosity of the resin/hardener it’s hard to get all of it out of the container you use for messuring. Secondly, I always stir in one container for a few minutes, then pour it into another container and stir it a few more to ensure a good mix. I’ve not had any problems since, even with smaller batches. I’m using a generic epoxy, but I doubt that Gregs product is inferior. regards, Håvard
Everybody’s taken it easy on you so I’ll say it. You screwed up the mix ratio. Nothing else makes sense. You probably mixed two parts hardener to 1 part resin. If you go back and measure leftover stock you might confirm this, but maybe not if your stock started in reverse ratio. On the other hand… maybe you mistook that old chicken soup stock for additive F.
I’m guessing it’s the residual left in your measuring devices that’s throwing off the mix, especially for such a really small batch. I always use three of the same sized containers to measure a batch, two for the resin and one for the hardener. If you use three separate containers, you will have three similar residual amounts in each container, thereby keeping your 2:1 ratio constant. I work in a brewpub and use small plastic sauce cup togo containers. You can get sleeves of these at Smart and Final AKA United Grocers, Cash and Carry. They come in several sizes. I mix up a batch and throw the cups away. I have mixed a ton of three oz batches with no problems. Good Luck, Gary Geist
filchwater- thanks for the response- i thought the same thing- i must have done the mix wrong- turns out im dumb, but not that dumb. i got the two parts resin to one part hardner thing down pat- i even got the right amount of add. f. after reading everyones post, im thinking that my major problem was that the resin & hardner were not in the magical temp. range to start with. that, combined with my having used two seperate measuring containers and then a third mixing container is probably where i went astray. in my “preparation” period today at work i marked a nice sized plastic pitcher with graduate marks at every ounce (sharpie, on the outside). im going to use this tonight to test out another sample after putting it in a microwave for 15-20 seconds. ill keep you posted. as far as my other batch, ive had some pretty interesting results. the cup i left in the 60+/- degree room is still gummy, but no longer in a liquid state (more like an amorphous solid). the cup that went in the 100 degree oven and cooled to room temp is hard as a rock- definitely solid all the way through (about 2cm thick). the third cup (70 degree) is somewhere in between, but closer to the gummy side. this would lead me to believe that the starting temp and curing temp were too low, with the added slight f@#% up of the mix ratio. is anyone in the market for flexy, gummy, but not tacky resin? i seem to be pretty good at making it. there has to be a need for this somewhere. again, everybody, thanks for all your help. as i was marking my pitcher today it occurred to me that every new shaper on this site should donate his/her first sold board profits to it’s upkeep. that should keep mr. swaylock drinking good beer while he is sitting at his computer. thats the least we could do. i will be the first to make the pledge after my work becomes presentable to the public.
before you go nuking your resin - just leaving it indoors might be ok if you let it stay inside long enough, or putting your small containers of resin ( 1-2 oz, no more than 100 ml or so ) in a pan of hot ( tapwater hot- say 100 degrees F) water, mebbe change the water a couple times at 15 minute intervals. This will work fine with small batches. Avoid using the family microwave - you never know when you’ll want to reheat some soup, y’know? If you must use the nuke machine, use one that’s not gonna be used for food ever again. Or else you’re likely to wind up with a microwave that’s not gonna be used for food ever again. Also- check your thermometer - it may be off a few degrees and a few degrees can make quite a difference. It’s bound to be colder up in NY than it is here surrounded by Atlantic, and my cellar here is a lot closer to 50 degrees than 60, even with the furnace in it. Your’s might be considerably cooler. Under 50 degrees a resin that’s meant to go off in 70 degree temps is gonna be real slow if at all. Some resins have low temp or fast hardeners available that are meant for cooler conditions, though I’d say only a few specialised resins will work at all once you get around freezing to 40F. Again, Greg is gonna have a lot more data on this - hell, it’s his resin - so I’d hold off to hear from him before making any major moves. hope that’s of use doc…
i’ve been using greg Loehr’s epoxy for 20 years now…Take a heating pad,put it in the bottom of a cooler( like the one you put your beer in)turn it on hi and this will keep your resin warm…HEAT THE RESIN ONLY!!! good luck ET