Hi Andy

The only way that I can see is to remove the superstructure, adapt the deck and put on a new superstructure.

Good luck

Paul

Ray of course means NiMh battery packs, not NiCads!

600 size motors would indeed do you, however not all 600ks are created equal, and there are considerable differences between them.

The Mtronics one appears to be fairly slow revving, and at 12v the spec says it will do 5200Rpm which is not much and at 7.2v might only do 3000 rpm.

The Graupner speed 600 rated at 7.2v produces 18000 rpm, at 7.2v.

The Aeronaut speed 600 is a 6-12v motor and it says develops 14000 rpm presumably at 12v. We could say that roughly on 7.2v you might have 8-9000 rpm on tap.

(all figures unloaded…which means just spinning whilst held in the hand)

So there we have it. Three outwardly similar motors with differing offerings.

As usual I would ask how fast do you want to go? In order, fastest Graupner, then Aeronaut and trailing, the Mtronics.

It’s horses for courses really. There is the brushless option but this gets much more complicated and will use two esc (electronic speed controllers). Unfortunately the choice here is massive and everyone has their own favourite setup. 

On the face of it, the Aeronaut ones are a halfway house, the Mtronics is for slower scale vessels hence the lower revs and high torque, the Graupner will deliver good performance using a smallish S35mm prop.

Ashley

Edited By ashley needham on 17/08/2020 08:39:39

You also ask what can be built on to the basic Sea Commander bull. At the risk of saying the obvious, the original design is excellent, you could go back to that. Then you could make improvements, carefull use of veneers can make huge difference as can a well chosen carefully done paint job. Make it into a gentleman's cruiser.

Chas

Hi Chris,

Yes I fly brushless & Lipos now, but back in 96 all I had was a S400 & 8 AA cells in a Model Designs FW 190 and it flew very well then moved onto the Blenheim which had 600's, those were the days

Regards Ray

Hi All

Totally agree with Chris E !!!

A good example is the banggood hobby surpass brushless motor, standard 540 motor mount.

Weight 132grams, 5mm shaft , a pick of three kv types.

Size 35mm diameter ,42mm long and handle 7-15volts(2-4S Lipo batteries).

The 1000kv 750Watts 55Amps.

The 1250kv 850Watts 65Amps

The 1450kv 1050Watts 76 Amps.

All Watt ratings are on 4S batteries.

I have a 30" Huntsman with a 1250kv on 3S and a good turn of speed.

Tested on 4S which turns it a bit of a speed boat!!!

As for brush motors the rock crawler ones are the only ones I found good specs on !!!

All on 7.2 volts(2S).

35 turn 13000 rpm, 45 turn 9500, 55 turn 7700 , 65 turn 7000 and 80 turn 5500.

The 80 turn I use in my fishing boats and handles up to a 3 blade 60mm prop.

Boat size about 860mm long( 2 Helens,1 Eileen and a French fishing boat).

Harry Smith

Edited By harry smith 1 on 17/08/2020 12:57:46

There is nothing like the sound of a big twin model aircraft doing a flyby, my engine of choice are old school Super Tiger 3000 as they are dependable and, with the right exhaust, sound super.

There is also nothing like the buttock clenching fear when you fly a big twin, if one of those motors die then you have massive Catherine Wheel on your hands closely followed by a big hole in the ground.

I'm always widely off topic.

Paul

Or to make them comparable with brushless (dividing rpm by 7.2v):

35 turn = 1800kv

45 turn = 1300kv

55 turn = 1070kv

80 turn = 760kv

Sensible decision Andy, they may not be the optimum, but they will be adequate. You can always do a straight swap upgrade later if the mood takes you.

Ashley