After 4 months on the project, I am getting very close to layup. To date, I have build all required tools for the job, laminated cores, bent edges, created base template and own all materials to move forward. I am hoping to press by the end of the month and get some days on them in March when there's good base and it typically snow in Maine/NH.
My questions are:
1) For those with West System experience, how many metering plunges of West Systems are you using to:
a) Wet base?
b) Wet 22oz glass?
c) Wet core, and do you look for absorbtion?
2) I will be pressing in a 60 - 65 degree basment, will 12 hours suffice in the press?
3) You don't flame prepare your bases do you?
I appreciate any help you can afford.
West Layup
Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp
Re: West Layup
I did not use west epoxy but I would suggest only mixing a bit at a time, no more than 3 or 4 plunges, just go back for more. The reason for this is that in the container if the glue starts to go off it gets out of control. If it is on the ski it is spread out so it does not get hot.Enduro_Skiin wrote:
My questions are:
1) For those with West System experience, how many metering plunges of West Systems are you using to:
a) Wet base?
b) Wet 22oz glass?
c) Wet core, and do you look for absorbtion?
2) I will be pressing in a 60 - 65 degree basment, will 12 hours suffice in the press?
3) You don't flame prepare your bases do you?
I appreciate any help you can afford.
When wetting out wet the base out then lay the glass on and try and squeeze the epoxy up from the bottom and then soak the top. It does not have to be thick and it is pretty obvious when the glass is wetted out. I use a flexible scaper to spread the epoxy.
In order to check your set time just glue some pieces of scrap wood together and set them near your mold. That way you can try and break them apart at various times and once you find the samples are glued you can release pressure on the mold
Are you using fast or slow hardener, I found that working by myself it took almost 1.5hours from the time I started until the ski was in the press and you don't want to have the cure start to early. I used medium speed MAS epoxy and vacuumed for 10 hours in a cool basement but I did have a radiant heater shining down on the mold assembly making it just warm to the touch.
I did not flame treat the base as this was already done by durasurf.
Good luck, Tony
Personally I would not depend on the pumps. The last time I used them the hardener pump would always have a bubble in the chamber. When I started weighing the parts I had a .10 oz error on the light side for the hardener.
I also found that I had way more waste when I used the pumps, because I was stuck with the pump ratios and had to mix 1 1/2 oz. at a min. (the last set of pumps from Raka would only do a 3 oz. batch min.) There was always too much resin mixed for the job.
When I started using the scale I had a better/more accurate mix ratio and less waste. Even if you just used one of those calorie counter scales from the local market, which I had to do once) you would be better off than using the pumps IMO. Try to find one that measures in grams and oz.
I can't help with amounts, but I did see measurements that the Kams have used. If you do a search you should be able to get a good idea of how much you will need per ski, and what tonyt said about mixing small amounts is a good ideas. It will take a couple of tries to get the amounts for each ski right. In most cases you could mix up some for the base and first layer of glass. Then mix more for the core and next layer of glass. You will have plenty of working time to do this.
If I understand some things I have read right you could mix the same amount of epoxy as the glass weighs + some for the base wet out. That would set you up for a 50-50 ratio glass to epoxy by weight in the composite.
Good luck. If this is first time you've used epoxies be sure to read the directions well and mix completely. Its very critical to mix completely or the final product will have problems.
Hafte
I also found that I had way more waste when I used the pumps, because I was stuck with the pump ratios and had to mix 1 1/2 oz. at a min. (the last set of pumps from Raka would only do a 3 oz. batch min.) There was always too much resin mixed for the job.
When I started using the scale I had a better/more accurate mix ratio and less waste. Even if you just used one of those calorie counter scales from the local market, which I had to do once) you would be better off than using the pumps IMO. Try to find one that measures in grams and oz.
I can't help with amounts, but I did see measurements that the Kams have used. If you do a search you should be able to get a good idea of how much you will need per ski, and what tonyt said about mixing small amounts is a good ideas. It will take a couple of tries to get the amounts for each ski right. In most cases you could mix up some for the base and first layer of glass. Then mix more for the core and next layer of glass. You will have plenty of working time to do this.
If I understand some things I have read right you could mix the same amount of epoxy as the glass weighs + some for the base wet out. That would set you up for a 50-50 ratio glass to epoxy by weight in the composite.
Good luck. If this is first time you've used epoxies be sure to read the directions well and mix completely. Its very critical to mix completely or the final product will have problems.
Hafte