Equipment calibration/testing

OK, getting ready for my first brew day on a new keggle setup. I'm going to brew an extract batch next week while I'm still saving for some more AG equipment.

I'm wondering what tests I can perform before brewing to figure out things like heat loss, evaporation, and efficiency in order to make the most accurate calculations when they count.

Has anyone tried mashing with a cheap substitute for malt to test efficiency?

Any formulas or test methods would be greatly appreciated. Also, anything I can do during the extract batch that will help with calculations for AG.

Thanks

When I built my new system I brewed a bunch of the same AG recipe in a row. In my case Scottish 60's. Ingredients were cheap. I measured everything fanatically until it was dialed in. It is all in a spreadsheet now so I can quickly and easily calcualte everything I need for a new recipe and consistently hit within 1-2points my OG.

You will be able to measure your boil off rate with the extract brew.

Good luck and have fun...

GT