Shane, The reason for the shaft breaking would be because when you are using the machine you are reving it up and down a lot. In order to reduce the problem I suggest that you run the machine at full RPM'S as that is how it was designed to run.
I hope that this is of some help to you.
Regards, Bruce
Regards,
Bruce
Please do not PM me asking for support. Post on the forums as it helps all members not just the individual.