What prop?
 

I have an atomic force motor and a wattage 30 amp speed controler and 1050 8cell MH bats. LHS told me to use a 9x6 prop but the controler cuts out after a few seconds of running full power. stuck an 8x4 prop, runs a few seconds longer but allso cuts out. Im trying to power a glider that has been running good on an OS .10 but I wana make this thing electric with good power with out spending to much.

RE: What prop?
 

Between the limitations of that battery, and lack of a gearbox, the prop is going to be pretty small. On the order of a 6x3, in fact, if even that large.

Those 1050mAh NiMH cells do well to produce 12 Amps on a continuous basis. An Atomic Force direct-driving a 9x6 prop is drawing upwards of 50 Amps or more by my estimation. Even with an 8x4, the current is in the 35-45 Amp range. Way too much for the cells to handle, and why the motor cuts out after a few seconds.

Between the plane and the battery, a cheap 6V Speed 400 motor with a 6x3 or 6x4 prop would suit your needs much better. Not only is that combination better suited to the battery, it's lighter by a couple of ounces at least, reducing your need for the power a big heavy motor can handle.