Polyester resin

[roko]

Hei people

I need some help with polyester resin core time.
i have polyester resin that is allready mix with catalizator only need to put in some hardner.
Now the question is how much hardner i need to put in 1 liter of poliester resin and still to have great time to work with resin.
Eny CORE TIME DIAGRAMS???????
Thank you for future answer!!!!

[yipster]

there may be diagrams but experience is the best teacher here, forexample cooler temperatures, but not to low, can double your time

[roko]

yipster thank you ,
i need info how long that time can be and mix ratio!!
What your exspirance can tell me?
Thanks once again

[yipster]

i have some good books on the subject and talk with my supplyer.
if you do a search youll find planty information. what i'm saying is get on your "trow away gloves", put some floor cover down and DO it.
if your not sure mix a little first and see how it reacts.
say half an hour is normal but time is critical and if resin gets hard before your finished dont try to use it.
really, just get started and soon enouch you master hand layup.

[yokebutt]

0.75% is usually considered the lowest safe amount as long as it's not too cold.

Yoke.

[roko]

thanks yokebutt

[Ssor]

I always weigh my resin and measure the catalyst with a 12 cc hypodermic syringe. From .75 % up to 2 % is the range that I use.
Trying to use polyester resin in direct sunlight will shorten cure time dramatically. But you must play with it a little to learn how it and the cloth behave. Get some pieces of scrap plywood and work up different shapes
, bore a big hole in it and make a patch, try glassing a 1x2x3 block of wood to the plywood. 1 1/2 ounce chopped strand mat will conform to a ball if you are patient. Work with a throw away bristle brush, disposable gloves and buy a can of acetone for clean-up. 2 ounces of resin is enougth to saturate 1 ounce of glass cloth with plenty to spare.

[gonzo]

The amount of catalyst is also proportional to the thickness of the laminate. Too much can make it go on fire.

[Sander Rave]

Just do it some testing and try to detect when the matter changes. That's the moment to stop. The ratio I use (as a hobbiist) is 1-4% and temperatures above 10 deg.C.

[roko]

thanks guys any more comment is more than welcome

[jimslade]

1 to 2,5 percent is the norm. trying to laminate in cold or very hot situations is problematic. always try a sample in the temps you are working with.