Al,

I have been using Pete's method for years. My digital scale was fairly expensive but it has seen many uses around the shop and kitchen and is a valuable tool.

But your method for the single cup balance would work well. You still have to do calculations though the same as for the scale.

Why not make two different weights, one which is 2.381 times the weight of the other (or whatever ratio your resin/hardener requires). That one would become your 'resin' weight. The other would be your 'hardener' weight. The weights could each have a hook and hanger to allow hanging the weight from the balance arm and/or each other.

To measure your resin you would place the more massive 'resin' weight on the balance arm, at whatever distance you need to end up with the batch size you want, then add the resin to the cup until it's balanced. To add the proper measure of hardener to the resin you would then hang the less massive 'hardener' weight from the first weight and add hardener to the cup until balanced.

If you mess up on the measure of resin, simply move the weight on the balance arm until it balances before adding the 'hardener' weight.

If you mess up on the measure of hardener.....

well you don't want to do that!

You would need an accurate and sensitive scale to calibrate your weights, but once that was done, no more calculations.

There are a few more details to work out to be able to pre-determine batch sizes, but they are relatively simple.

Just something else to think about,

Doug K.