HI. In my 1/24 scale Perkasa MTB (48") I have a brushless motor and use an inline 60 Amp car type fuse. Never had it blow it's just in case I do something stupid. The Lipo 12,500 mAh batteries are capable of over 300 Amps if shorted out.

I have both a 1/35 Elco on the go as well as a 1/72 PT15.
The Elco has a 2 brushless set-up so no fuses in there then.
Just for fun in the smaller boat I'm actually trying out one of the thruster type drives rather than props and in that I'm using a brushed 380. Can't remember off hand the esc numbers but I'll get them tomorrow and can get some opinions on recommended fuse.
Thanks again all.
Update: esc is 60A waterproof and battery is lipo 2200mAh if that's the info needed?

In favour of fuses??

In Brushed motors.. Maybe! the the event of pond weed or sticks etc. stalling a motor, they could save the ESC/Motor from burnout.

In Brushless motors... Maybe NOT! Brushless motors and ESC's have the potential of sinking much more transient current than most DIY fuse holders can handle. Every time you overload the fuse holder, it will heat up. Every time it heats it stresses the contacts and increases the resistance which causes more heat. The path to a final failure of the holder has started.. Brushless ESC's have far more motor/esc protection technology in them than a fuse will offer. In these setups, I think Fuses are a liability not an asset!!

Hi jostro65.

PeterD's experience is very important and valuable.

The car blade ones are the ones I use too.
As for the amperage to cut, it depends on what you want to protect.
For example, for an electric motor (I'm talking about the fuse between the motor and the esc) 10 amps could be too few.
It could break and open the circuit when it is not needed.
For example: for a motor (which has an operating voltage from 3.6 V to 8.4 V, 18200 rpm, no-load output current: 2 A, output current at max efficiency: 12 A, output current at blocking 85 A) I would not put a 10 A fuse.
Do you have data for the ESC, the batteries and especially the motor?

Ciao jostro65.

I was waiting for someone more experienced and skilled than me to answer, but I decided to write because I'm sorry that you haven't had any answers yet. It must have slipped by (apart from PeterD of course).

This is always a very interesting topic and always much debated in this forum.
I am always in favor of fuses.
I will summarize in a few words the concepts that in my opinion are in favor of inserting one or more fuses.
The main problems that can concern a RC naval model are fire, sinking, loss of control due to failure (the ship remains in the middle of the lake or goes in an unwanted direction).
Of these problems, the most serious and irreparable is certainly fire.
Sinking (not caused by fire) caused by collision is very rare and in any case not connected to the presence or absence of fuses.
Possible infiltrations can cause sinking but allow you to understand the situation in time and in any case have no connection with the presence or absence of fuses.
Loss of control can be caused by the fuse because if it breaks it opens the circuit.
In this case the model could still be recovered intact.
In the same situation that caused the fuse to blow, a fire could have been generated or an important element could have been damaged if the fuse had not been there.
In addition, there are cases in which the fuse intervenes and navigation is not completely interrupted.
I will give an example (it is a particular case not a general one):
"A model ship RC has two electric motors.
Due to a jam in the propeller (leaves, branches, or a wire on the surface has tangled and blocked the propeller) the motor is stopped and absorbs the maximum stall current. This is not a rare case.
If the modeler continues to push the motor forward and does not have a fuse, the electric motor will probably be damaged.
If the modeler has placed the fuse between the esc and the motor, the fuse will blow and the motor is safe.
I believe that the modeler can make his ship return home with the other motor and the rudder."
Of course, if the overcurrent occurs between the ESC and the batteries and a fuse placed there trips, by opening the circuit it cuts off power to everything downstream.
However, without considering that it could have saved the ESC and batteries, if the modeler has powered the radio and servos (rudder and winches if there are any) with a separate battery instead of powering them with the ESC's Bec, he could slowly get closer using the rudder as a paddle.
I hear someone has done it.
I power the receiver and servos with a separate battery and isolate the BEC.

There are various types of fuses, you can choose (as more than one modeler has suggested) the restoring ones.

I am of the opinion that it is good to put fuses both between the ESC and the motor and between the ESC and the battery.

The problem with fuses is the right choice of their sizing.
We have discussed this a lot in the past.
If you are interested, I can search for old topics and post the relative links or give you a summary.

I have not used fuses - yet. I had an esc overheat on one occasion with a lot of smoke coming out of the hatch. It was the fastest 100 meter sprint I have ever made, luckily the water was shallow and I was able to turn off power and rescue the boat. Brushed motor and esc but I may have been stretching things.

A simple inline fuse would have saved a lot of anguish, not counting the near loss of that boat.

When I did my 1/35 the deck does have the screws, but instead of glue, I used clear silicone around the edge then the screws. The thinking was that if I ever needed to remove the deck it would more easily come apart. I have no water issues with this method.

If your kit has port holes, those must also be sealed or glue them in and paint black as light would rarely be visible during operation.

For the access below deck, adding a plastic bulwark around the opening is a safe way for keeping water out.

If you like what I am doing ask for more information.

My model uses 1 brushed motor.