Here is an email correspondance between Nick from Metrix and myself.

Hi Nick,

My name is Nathan, one the researchers on this project. Some of the issues we are having are that some of the stepper motors are really hot.

This is normal for steppers. Even if they are slightly above "too hot to touch" they are still happy. They should not got hot enough to boil water though. The stepper drivers should not get this hot though, if they do, they will need heatsink on the driver chip or you need to turn the current down until you can fit them with heatsinks.

When the z-stage is travelling up it does something to make a lot of noise.

This could be the stage stalling out, it really depends on the noise. A Z axis crank is a good way to tell if the Z axis is stalling since its motion would not be fluid during a Z move if it was stalling

Another issue we are having that is probably related is that when printing the makerbot will re-adjust its zero settings and start printing at a different location.

This is a problem with all systems that are open loop, though there are things you can do to reduce the chances of this happening (Most errors occur when pausing/stopping a build or if your skienforge settings are incorrect)

We just filed down the side of the z-stage that is closest to the chips. It was catching on the bolt heads located on the inside.

If you have any insite into these issues that would be wonderful.

Thanks,

Nathan