hI Peter the reason for the half size d's is A, keeps the weight down B, because they are high amp they will give their power up slower and give me more run time with the set up I'am using going on past experience,as I'am going for a more scale speed then power boat C, already had them at hand D, as I said working to a budget, if I had the money to by brushless and lipos I would but one dose not have the money at this time so will have to stay in the dark ages for the time being


bat44

can I ask is there a reason why you are using half "d" cells as they are not usuly very good at giving up there power in a hurry more industrial use.

peter

hI rooksailor as I'am on a budget I will be using 600 8.4 graupner motor with mtroniks 25 amp speed controller powered by 9.6 3600 nimh half size d cells pushing 35 or 40 mm prop on my 34in fire boat should get up and go,if you go to the photo gallery you can see some pics of my boat


bat44

rooky its a very difficult question to answer, really depends on budget, and the performance you want, but it does not end with the motor, there is the battery power, and the prop, all influence the run time, speed, and efficiency. Brushless motors are really good for performance, but your esc will not work with one of those. Have a look at the section that covers power set up, you can choose what sort of performance you want. I personally use a graupner 700 bb turbo, a choice of 3, 12v, 9.6v, and 8.4v. The 12v needs plenty of volts to make it perform but on direct drive went well. I now use a gearbox and have the 9.6v motor installed

pmdevlin.
Many thanks for the reply. I really don't have a budget, but I would prefer to buy once, and get it right, and of course the best and easiest way is to ask what other model sailors use in the identical craft. As far as performance required, I would like it to move as near as to the original craft. (scale speed of course) Dave suggested I try brushless but without using lipos, maybe that's the direction I will try.

Rooky. I have a 34" Fireboat and would recommend using a brushless motor. Giant Cod have some available. As Peter says you will need to also buy a speed controller, just make sure you buy one that will reverse from the radio signal. You can use NiMh batteries but if speed is really Important consider LiPo's, but this will add considerably to the cost as special chargers are also required.
As the 34" boat is quite small it is Important to keep the weight to a minimum and I found that Brushed motors coupled with the batteries required to produce the power made my model far too heavy. My boat with motor, ESC receiver but without batteries weighs 3lb 15oz, 4lb 4.4oz with 11.1v Lipo, 4lb 15oz with 8.4v NiMh.
Good luck with your model
Dave

rooky its a very difficult question to answer, really depends on budget, and the performance you want, but it does not end with the motor, there is the battery power, and the prop, all influence the run time, speed, and efficiency. Brushless motors are really good for performance, but your esc will not work with one of those. Have a look at the section that covers power set up, you can choose what sort of performance you want. I personally use a graupner 700 bb turbo, a choice of 3, 12v, 9.6v, and 8.4v. The 12v needs plenty of volts to make it perform but on direct drive went well. I now use a gearbox and have the 9.6v motor installed