I know it varies depending on what you use but just post what you are using and how much epoxy you use per pair.
I would like to get entropy but I want to figure out how much I need to order. I dont want to over/underorder.
Thanks
About 1/2 kg of resin per pair with 750 gsm (22oz) glass
180 skis 100mm underfoot - 50% more if I'm sloppy
so a gallon of resin will do about 8 pairs?
I typically mix 800g for a 185 cm ski. I may try to get away with less. Something around 700-750g since I usually have about 100g give or take left over.
i'm around 900-1000g per pair using entropy, working on cutting this back. need more experimenting, maybe a separate wet layup table. why not buy a small kit and test it out?
also, i see your in NH...these guys sell entropy resins, can probably save on shipping coming from RI versus entropy hq in Cali
whoa thanks a ton for showing me that
it's sort of a one stop shop because they have a lot of composite materials too, although they didn't have the entropy CPM resin which is their compression molding specific resin. I'm not sure if any of the other resins would work, does it have to be a compression molding resin specifically or can it be any resin?
WOW thx
Jamestown distributors not too far from me
. If they have it... probably Comprising One have Entropy too. Only Jamestown website showing no super sap CPM.
100/1000 for press without heat?
I would only use heat curing epoxies. Non heat-cured epoxies are like 1/3 as strong as heat cured.
yeah i use the 100/1000 for room temp cures, no heat yet for me
For now I don't have plans for blankets because I'm not an electrician and somewhat uncomfortable doing electrical work like making PID controller.... it shouldn't be difficult to make the blanket....anybody up to group build of blankets?
I mean I live fairly close to you so I would be down, but I won't be available to do anything until late June, if you want to wait that long
I can get 4 -5 pair of skis out of a gallon of resin, 1qt hardener. I've been using QCM epoxy.
I'll have to check out Jamestown pricing for Entropy. I'm in MA. I could take trip down to RI and make a day trip out of it.
I think Jamewstown is just an online supplier, and they dont have the cmp resin, Im not sure how good the other ones are
My rule of thumb is 1:1 (not 100% exact, but you get a good wet-thru)
ex. 100g FG = 100g epoxy
Carbon fiber draw more, 1:1,5 (ca...)
There may be some info on this forum On the difference between the entropy 100/1000 vs the CPM products. From the looks of the data sheets viscosity is the main difference.
Desi is pretty good about answering questions so someone could
Contact him to see about this.
the problem with that system is that it has a 7 day cure cycle, opposed to CPM's 20 minutes. CPM is also a little stronger
i havent had any problems with the supersap 100/1000. press for 9-10 hours no heat (45-50 psi), leave in press for 24 hours, take out (usually bring inside) and wait 5 days before cutting the flash. long process but works. i hope to make the step towards a heat blanket or two this summer
unfortunately local composite one don't carry in stock Entropy...only California branch
.
ah thanks for the update MR
I'm using Entropy CPM, and for the two pairs I just did this last week I used 400g per ski (800g for the pair). Works out pretty good for me to mix up two batches of 200g worth of epoxy in two cups (with the 100:40 ratio, that's 57g of hardener in the cup, then add resin up to 200g), I use 200g for everything below the core, and 200g for everything above the core.
I got the 3qt kit, but I'm not sure how much it weighs, so I don't know how many skis I can get with the kit.
Wow tizz that seems low to me, what weight glass are you using? With 22 oz glass I feel like there is no way I could use less than 700g. Granted the skis I build are generally long and wide but not too much different from your designs.
We are at about 900g total for a pair of longish fat skis with the cpm. Prolly too much but better to much than to little.
I'm using 19oz triax, plus a 3" wide strip of uni carbon top and bottom (can't remember the weight of the carbon, it's not much). The powder skis I just did are 160cm length, 155/130/145, and with 400g of epoxy I got nice and even wetout during the layup with basically no epoxy left over, and when pressing I still got a fair amount of squeeze-out. I figure as long as I'm getting squeeze-out, there shouldn't (hopefully...) be any dry spots inside the ski.
Nice, I hear you on the squeeze out, but I'm with MM on this one. I'd rather use a bit more epoxy than be worried about potential dry spots.
I think I can comfortably get away with 700g. I typically use 300g above and below the cores and then 100g as a top coat. Right now I'm mixing 800g in 4 batches. But I usually throw out 100-150g at the end. I think I'll just do 3 200g batches and then mix what I need to do the top coat. This might extend my material a little and save a couple $$ even.
I always just weigh my fiberglass, match that weight with epoxy plus 10-15%
