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[ferny]

Here is my attempt at a Flower class, all points of praise and criticism welcome !

I have replaced the kit cross members with I beam styrene for strength .



Also made servo mount and rudder access panel, I like use lite ply as I find easier to work with than styrene sheet . The kit rudder has been epoxied to a small brass one .


All though I have seen it recommended a lot the 385 motor looks tiny in that huge hull. Also not sure if I use 6v sealed battery or 7.2 lipo/nimh or which esc to use with either one?

[Shipmate60]

For extra strength on mine I glued a thin strip of evergreen plasticard over the hull joints.
The motor is fine.
When getting her ready for sailing ballast her deep which gives her a far more realistic motion.
6 or 7.2 volts will be fine.


Bob

[Netleyned]

Looking good so far.
The strenghthening is
sound advice.
I assume the motor is not
fixed in position yet!


Ned

[ferny]

Thanks and no its not :)

[RAAArtyGunner]

And here was I thinking it was mounted to overcome torsional forces and aid steering.

As someone has said what do I know

[HMS Invisible]

...All though I have seen it recommended a lot the 385 motor looks tiny in that huge hull. Also not sure if I use 6v sealed battery or 7.2 lipo/nimh or which esc to use with either one?

A 385 motor has enough power but insufficient torque for the scale propeller without a reduction gear. The larger and heavier 555 motor would be perfect.

[ferny]

I was planning on using a 30mm prop as I have one already

[HMS Invisible]

If you have a tacho you'll find the 30mm prop drops a direct-coupled 385 rpm below 1/2 its no load figure.
Most of the power will be converted to heat.

[ferny]

Oh back to the drawing board, I take it a 555 motor has plenty of torque but low rpm? what voltage would you recommend?

[HMS Invisible]

It has. If you can stand the noise, a 385 with a 3:1 reduction or smaller prop will be ok.
2s lipo (7.4 volt) or 7.2 NiMh for battery with additional ballast.

[ferny]

Like this : http://www.robotshop.com/uk/rs-555-motor-7750rpm-12v-2916oz-in.html ?

[HMS Invisible]

Yes, like that, but the stall current figure of 15 amp at 12 volt is suspect
It needs a 3.2 coupling insert.

[TheLongBuild]

Good build here, think it is a static build.


www.britmodeller.com/forums/index.php?/topic/234929377-172-revell-corvette-snowberry/&page=1


also this by Dave Abbott


www.modelboats.co.uk/news/article/hmcs-snowberry/10039

[TheOldMan]

A 385 motor has enough power but insufficient torque for the scale propeller without a reduction gear. The larger and heavier 555 motor would be perfect.

In the Compass Rose I have used the 385 and a 7.2 Ni MH battery, strait drive, she is very quiet and has more than enough speed, and its like scale speed as well, you need a lot of ballast, the prop is about the same size as the kit one. Re enforce the front as mine split when i dropped it and it could happen if you ram it against something. also see Dan Lord's and other thread on this model, hope it helps.
chris

[Plastic - RIP]

In the Compass Rose I have used the 385 and a 7.2 Ni MH battery, strait drive, she is very quiet and has more than enough speed, and its like scale speed as well, you need a lot of ballast, the prop is about the same size as the kit one. hope it helps.
chris

I use a 385/7.2V with correct prop too - no problems. At full throttle it almost planes 

[HMS Invisible]

In the Compass Rose I have used the 385 and a 7.2 Ni MH battery, strait drive, she is very quiet and has more than enough speed, and its like scale speed as well, you need a lot of ballast, the prop is about the same size as the kit one. hope it helps.
chris

You don't get the noise without the gears but most of the power is converted to heat.

[Captain Povey]

Hi, When I built mine I was quick to put the assembled hull in a bath of water and soon discovered it leaked like a sieve. It might be worth checking before you go too far building up the superstructure and fixing the de )cks that all joints are water tight. Its easier to seal it now that later. I got all my running gear from Deans marine. Nice work. Graham.

[TheLongBuild]

Hi, When I built mine I was quick to put the assembled hull in a bath of water and soon discovered it leaked like a sieve. It might be worth checking before you go too far building up the superstructure and fixing the de )cks that all joints are water tight. Its easier to seal it now that later. I got all my running gear from Deans marine. Nice work. Graham.

what motor did you use ?.

[Allnightin]

I have run a Flower class for almost 30 years using what I always believed to be a Mabuchi 385 on a 6V 4Ah battery via a Bobs board controller turning the kit propellor directly without any gear reduction.  The motor is the same dimensions as those stated for the 385 and is 5 pole and never seemed to get particularly hot.  It is true that the prop is larger in diameter (40mm) than the motor but is fairly fine pitch and I always had good performance from this set up with the wake pattern looking comparable with full scale.   I know a lot of people change the prop for a higher impact type plastic one which probably has a steeper pitch but if it works with the scale one supplied why change at all?

[Captain Povey]

Hi Longbuild, Sorry but I cant remember exactly what the motor is and I cant go and look as since the house move all my boats are in store at a friends house. I do recall that it is not very big and is a direct drive to the prop shaft. It has plenty of speed and runs off a NiMi 7.2v battery through an Mtronix speed controller and planet t5 Rx. When I get them back I will have a look. Cheers, Graham.

[g6swj]

This is the motor in the Dave Abbot build of Snowberry - sorry if you already knew this - have not read the whole thread...

Regards
Jonathan

[ferny]

Thanks for all the info gents watch this space for developments.

[ferny]

Well as predicted she leaked like a sieve!




So while the glue was setting on hull I made a start on the electronics.





So in the box is a mock up of an Mtronkis ESC, a cheap brushed ESC to contorl the lights from channel 6 it can control the brightness and by using forward and reverse it can switch from red to white all from the rotating knob on the TX. It also contains all the electrical conections in one place.

[ferny]

A bit more done this week, attached rear deck and re work large opening ( seem to build every thing at least twice!)





Also cut down and sanded the rudder post to shape.





And made a start on the electrics/controls





Thanks for looking

[gregk9]

If you needed to reinforce  the joins, especially bows and along the keel, id suggest some stabilit express or UHU acrlyit alternative. makes in to a nice runny resin but sets like stone and holds plastic together with ease.