@merchant67
The fuse is going to depend upon the current draw of the motor. That will be determined by the motor windings, the weight of the model, whether the motor is geared or not, and the prop size and pitch.
One way to cover you bases is to place the motor in a holding device, like a vice, but don't crush the motor. Place an ammeter in series with the motor leads and, here is the tricky part, you want to determine the current draw when the motor stalls, ie, with current flowing the shaft of the motor is held immobile. This should be done some that it is a momentary reading and load on the motor, otherwise damage can and will occur. That current reading will be the stall current and can be used as a guide to determine the fuse, or circuit breaker size, for use on your model. Your choice, go either side of the reading you got.
Folks will advise either way.
I personally prefer to use auto-resetting circuit breakers because they will reset and hopefully allow you to get your boat back. Fuses are generally more reliable, but one time use only, AND, you need to have a way to get your boat back to shore.
The fuse is going to depend upon the current draw of the motor. That will be determined by the motor windings, the weight of the model, whether the motor is geared or not, and the prop size and pitch.
One way to cover you bases is to place the motor in a holding device, like a vice, but don't crush the motor. Place an ammeter in series with the motor leads and, here is the tricky part, you want to determine the current draw when the motor stalls, ie, with current flowing the shaft of the motor is held immobile. This should be done some that it is a momentary reading and load on the motor, otherwise damage can and will occur. That current reading will be the stall current and can be used as a guide to determine the fuse, or circuit breaker size, for use on your model. Your choice, go either side of the reading you got.
Folks will advise either way.
I personally prefer to use auto-resetting circuit breakers because they will reset and hopefully allow you to get your boat back. Fuses are generally more reliable, but one time use only, AND, you need to have a way to get your boat back to shore.