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[dickyp]

I am considering buying one of "veteran model boats" 46" air sea rescue boats.

I am out of date with modelling and would have no idea what motor, controller battery, etc to use.

VMB are suggesting a Graupner 900 with 3-6v 7 amp gelcell batteries and 35amp controller
or
a brushless motor controller with  nicklemetalhydryde batteries

It is all double dutch to me and your advise would be appreciated

For anyone that may be interested, the current cost is £220 + p & P

Thanks

[john s 2]

A Gruapner 900 will not be very powerful on 6v id go for 12v.Action do a motor as good for a lot less,its as good. Batteries are more controversial Nimh would be fine but please remember that run time would be short unless of a big capacity.John.

[Shipmate60]

I would consider 2 shafts in her.

Bob

[dickyp]

Pardon my ignorance but would I require 2 power sources and 2 speed controllers ?

[HS93 (RIP)]

which particular boat are you building. is it the firefloat mk2/fireboat kit that you are building from lesro / Vintage Model Boat Company

Peter

[HS93 (RIP)]

where are you by the way?

Peter

[dickyp]

I have not yet purchased the kit. My plan is to purchase one from Vintage Model boats, Mike Cummings, but untill I can work out what the final cost is likely to be, I don't wish to commit.

VMB have been very helpful in providing me with information so far, but I was concerned that their suggestion on the type of motor, speed controller and battery mat not be what forum members may use, considering the size and potential weight of the boat.

I live in Huddersfield

Thanks for your responses

[HS93 (RIP)]

I am helping someone convert a old 46 in boat to twin screw we are using two brushless motors as they are cheap and more deficient we will run each on 14v nimh's I have also done a conversion of the 34" version some 20 + years ago and it is the way I would go if building from scratch, Ill post a picture of mine but all it is is a pair of keels for the new shafts on the pre built 46" boat we went a different route and I will ask the owner to post some pictures as it is not my boat. there is plenty of room, the idea is to use two buggy packs per motor. but you could even go lead acid if you wanted to just get reasonable performance and long runs, the boat has the displacement to take most battery set ups.

Peter

[dickyp]

HS93

Thanks for your post

As I say I am out of touch with things

Could you advise type (name) of motors, speed controllers and battery. Do I need 2 of each?

Sorry for sounding thick but I just don't know

Any idea on costs ?

Thanks again

[HS93 (RIP)]

the batteries are just 7.2v buggy packs depending on how long you want to run and how much you want to pay Ill get him to come o  with the motors used and some pictures and ill find some of the way I did it when i had a 34" kit build
 you would need 4 batteries and two motors and two speed controllers
peter

[irishcarguy]

Hi, Johns suggestion of contacting Dave @ ACTion will be a big help to you. They make a controller that will handle both motors at once & their electric motors are as good as the best you can buy elsewhere & a lot less than most others. As a bonus Dave will do your wiring layout too, just ask him. Mick B.

[red181]

dicky, what sort of performance and runtime do you want? this will determine what set up to use, just plod around all afternoon, or very fast, which will dramatically shorten run time, or scale speed? what sort of budget do you have, for motors, speed controllers, and battery packs, then we can offer constructive advise to fit around the desired performance and budget,

The 900 on a gel cell will give  areal slow performance, but will last for ages

[dickyp]

Hi Red181, thanks for your input

What I'm trying to work out what it is likely to cost in total as I'm short of funds being out of work.
I know the kit costs £220 plus p & p and was hoping to get it in the water for around £320 (hopeful)
I was hoping to get the boat plaining for say 10 minutes and lasting for 20 - 30 minutes overall
Please be aware that I no absolutely nothing about controllers and batteries, so your help appreciated.

[Norseman]

Hey dicky p

you sound a bit embarrassed about asking the questions - but please remember that there will be lots of people like me who read the answers and learn too - so ask away mate. I see Peter has been helping you - just as he did for me when I wanted info. Great place this forum.

Regards Norseman

[dickyp]

John s

Have you any contact details for dave@action please

[john s 2]

Hes listed on the traders section of Mayhem. You could google Action electronics for his Website, or ring him on 0115 960 7951. John.

[HS93 (RIP)]

There is a web site that was started for people who have an interest in fire boats . you will find info on there about powering your boat

http://modelfireboats.com/index.php

you will see some of thekits that have been built from Mike Cummings, plus original aerokits and others, one thing to do is before you start glueing the first pieces together think about weight, and remove as much as possible that way your run time will be longer as you will not need as much power to make it plane, also if you decide to go twin screw it can be done very simply at the start,I would build the hull with twin screws and worry about motors later, but before you skin it. prices for brushless have drooped so dramatically over the last year or so and power has increased they are about 20% more efficient and getting better and cheaper all the time.

Peter

[red181]

Hi Dicky, everyone will have their personal preference on how to power the boat. I am biased to brushless and lipo batteries , and this is just my opinion!

My 3 foot aerokits fireboat is powered by a graupner 700 bb turbo, 9.6v, running on 19.2v, and 45mm  propshop cleaver 3 blade prop, and a gearbox reducer, its fast for 15 mins, and is over scale speed. If it was direct drive, on say 14 volts, it would be very acceptable speed. That setup, approx £15 for motor, a good electronise 35amp speed controller, £35, two 7.2v lipo battery packs, or two 7.4volt nimh packs, probably £12 each (all approximate). You could use a plastic 2 blade "x" prop, £1.50, and have a reasonable set up, this is all a brushed setup.

My current build is a 4 foot aerokits fireboat restoration. THis is a completely different set up. Twin screw, direct drive, brushless 900kv motors (£14 each from giant cod, UK seller) two reversing Turnigy speed controllers (£25 each) and will run on 14.4 volts per motor, so 4  2 cell lipo packs, 2 per motor, approx £10 each. This will be a brushless setup, much faster than the other one, more serious, and more money, but thats the way I like them, fast!  

As HS93 has suggested, go on the fireboat website, look at all the videops, and pick what suits you in terms of performance, then you will have a good idea what to do, then, keep an eye on ebay for some bargains with motors etc, I got two Align brushless motors for my Huntsman, should have been £80 each, for £15 and £25, risk was second hand, but rc helicopter motors are usually less stressed than boat motors so it was worth the gamble!

The smaller boat, with simple direct drive pictured here