Balancing of a turbine

What a busy week i have had this week, with allot of it taken up with messing around with turbines, not a bad way to spend some time. well this weekend saw Brett from ausjets.com and myself balancing the turbines, most would assume this would have been done in the factory and in most cases it would, one was already balanced and tested but due to the MASSIVE delay the only way to retain some form of reasonable time line was to send the other motor out untested and not balanced, this was ok with me as we had agreed that we would balance them our selves once they arrived anyway, balancing is is one of the single most important things we can do for the turbines, it will prolong the life of the engine as well as the bearings, it also helps stop the engine from ripping it's self apart. below you can see one of the turbines being spun up to find out where the imbalance is.

you can see in the picture below that the target on the left is the rear turbine and the target on the right is the front. picture looking at the turbine head on or from directly behind, the dot is showing where there is an imbalance in the turbine and impeller. In this case the rear turbine needs 3.79 grams taken out of it, while the front only needs 153 milligrams taken from it to get it just right. The 220 and 209 degrees at the bottom is not temperature, it is actually showing how far around front top dead center you need to remove  weight, in this case it is 220 deg of 360 deg on the rear turbine and 209 deg on the front. 

Below you will see Brett as he shows me where we need to take some weight out of to have the turbine spinning true. this is simply done with a marker and then grinding it out.

below you can see as Brett takes out some meat from the rear turbine to help with the balance of the engine. That line you see on the center nut is reflective tape and helps us tell where top dead center is, it also reflects a laser top help us tell what speed we are spinning the motor up to while balancing it.