Hello,

Hi,

Thank you and helpful.

Hi, the ratio 100:30 is the ratio of resin to hardener so:

you have 100 parts of resin to 30 parts of hardener, or 100g resin, 30g hardener.

The 1.3 factor noted above is the multiplier to work out the resin based on the total amount of resin required so:

if you have 50/50 fibre/resin ratio and 300g of fibres you use 300g resin (total mixed weight),
From that 300g of mixed resin you have the main resin and the hardener at a ratio of 100:30 so: 300 / 1.3 = 230g resin, therefore the harderner is 300-230 = 70g or as mentioned, on the scales pour on 230g resin and top up to 300 with hardener

100:30 means that for every 100 grams of epoxy resin you need 30grams of epoxy hardener, for a total of 130g of final resin mixture.

This 1.3 factor ozonedge used in his calculation is actually 130g divided by 100g in the above example, 130/100=1.3. or the ratio of final mixed resin divided by the epoxy resin used. It's a maths thing...

Your homework: calculate the following. Take pen and paper and a pocket calculator and try to work it out.

A) How much hardener do you need for
1. 10g of epoxy
2. 50g of epoxy
3. 80g of epoxy
4. 220g of epoxy

B) You have only 66g hardener left. How much epoxy resin can you mix together with this limited amount?

C) You need 286g of mixed resin. How much epoxy and hardener do you need for this mixture?

Report your results and we will check whether they are correct. (If you like)

You really need to be able to solve part A. This is most important. If you can solve B and C that's a bonus.

Thank you Brainfart,

Oops, for the last three I accidentially picked the same example. Sorry.

Yes seems to be right.

If you are not sure, just keep it simple and mix in batches of 100g of resin.  That way for every 100g of resin, you need 30g of hardener.  Simple enough to do in your head and be confident youve got it right.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Hi,




Also suppose you have 5 kg Epoxy. Then the Resin would be 5kg x 0.77 = 3.85 kg and the hardener would be 5kg x 0.23 = 1.15 kg.

What Warren said,or be really lazy and use the back page of the EC catalogue as it has a mixing ratio chart for most of the EC products (great for mixing very small amounts )