Going to do some brushless motor tests.....
I've been doing some motor testing as well, for the EezeBilt boat range, so I'm looking at smaller sizes. Early days yet, but I do have a test rig. Some data:
Brushless Tower 2408-21T-3A - KV 1400 this one -
http://www.brchobbies.co.uk/?page=shop&action=additem&item=1849v dry batteries - coarse 30mm prop - thrust 125 gm fine 30mm prop - thrust 67 gm
6v Gell Cell coarse 30mm prop - thrust 238 gm fine 30mm prop - thrust 255 gm
7.4 v Lipo coarse 30mm prop - thrust 395gm fine 30mm prop - thrust 427 gm
Small 3-6V brushed motor - this one
http://www.mutr.co.uk/images/mm28.pdf 4.8v NiMh coarse 30mm prop - thrust 75 gm fine 30mm prop - thrust 22 gm (around 1.4A)
6v Gell Cell coarse 30mm prop - thrust 162 gm fine 30mm prop - thrust 192 gm (around 2.2A)
7.4 v Lipo coarse 30mm prop - thrust 209gm fine 30mm prop - thrust 269gm (around 7A)
I have two more brushless - a Tower 2410-12T-3A Kv 1000, and an Emax CF2822 (see Giant Cod) to do, as well as a Graupner Speed 400 6v. I was going to put the data up on the EeZeBilt web site once I had interpreted it, but I probably need to get a bigger selection of props together. What seems to be happening is complicated - sometimes the motor power is limited by the amps it can draw and sometimes it is limited by the drag on the propeller.
All the above figures are from a static test rig (AKA my bathroom). When the boat is actually running the propeller will be unloaded and figures will change considerably. In fact, you need to baffle the water in a bathtub, otherwise it swirls and makes readings vary....
DG