Model Boat Mayhem - Forum

Dry Dock / Shipyard: Builds & Questions => Pleasure boats, Sports, Race, Power and Leisure Boats: => Topic started by: Eddie W on July 24, 2018, 03:18:54 PM

Title: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Eddie W on July 24, 2018, 03:18:54 PM
I am currently building the above and am at a stage where I need to decide on running gear. Can anyone please suggest a suitable motor, ESC etc either brushed or brushless? Research I've done suggests that the boat is underpowered if you use the Dumas recommendations.


Thanks
Eddie
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Martin [Admin] on July 24, 2018, 04:05:16 PM
 


(http://www.dumasproducts.com/images/1241_1.jpg)

http://www.dumasproducts.com/product_info.php?products_id=180

Length: 40-1/2 inches
Beam: 10-3/4 inches
Scale: 1/8th
Running Hardware: Included in kit


*Additional parts required for R/C: (sold separately)

Power: #2025 High Speed Electric Motor
A great little economy high speed electric motor that can be used in lots of projects. This is the motor we use to power our Chris Craft line of models. Includes mounting brackets and complete coupling for 1/8" shaft.

30 Turns
Can operate on 6v - 8.4v
Length:   2-3/4"
Diameter:   1-7/16"
Weight:   5.6 oz.
Will draw 8 to 10 amps and not for use with props over 1.5" max.
  Also should not be used with adapt-a-drive gears.   
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Martin [Admin] on July 24, 2018, 04:09:43 PM
 
I would say 'Go Brushless!'
 ( ....but then again I would always say that! )

But what Brushless motor? .... recommendations Gentlemen... Ladies!
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: martno1fan on July 26, 2018, 08:12:34 AM
A lot  depends on the weight of the model as to what motor you could use .
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: canabus on July 26, 2018, 10:26:16 AM
Hi Ed
I recommend a Hobbyking 3639-1100kv 35mm brushless(bolts straight in replacement for the 35mm 540 brush motor).
The drive line is totally to small and requires a 4mm setup .
Prop size a 2 blade 40mm 1.4 pitch or a 3 blade 37mm 1.4 pitch.
ESC 60 Amp and a 3S lipo 3700mah.
I have this setup in my 1920 SG&K Gentleman's Runabout and works well.
Good run time and speed, maybe a bit over scale speed.
 
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Hotglove on July 26, 2018, 07:47:06 PM
Acting on advice from Canabus I fitted a Turnigy 3648 1450kv motor and Leopard Hobby (Hobby Wing) 120a ESC to my Dumas Chris Craft 1930 runabout. Prior to the conversion it was fitted with an MFA Torpedo 850, the difference is remarkable, the boat lifts on to the plane effortlessly and after a typical mixed 45min run on two 3s 5000 mah Lipos the motor temp is under 50c and the ESC and batteries are not much over ambient temp. this weekend I spent more time than usual at higher throttle settings and the battery voltage after nearly an hour just dipped under 12v for the first time.
Still experimenting with props to try to find the optimum setup, tried 35, 40 and 42mm props,(all X types) with the 35 giving the best performance so far.
Testing with tachometer the motor unloaded gave 18600rpm, 42mm gave 12000rpm, 40mm 14000rpm and 35mm 15000rpm   
Currently running the original Dumas 3 blade bronze prop which looks great (polished) on display but seems to spin rather too easily  (17500rpm) and moves less water in the test tank (paddling pool)
When it comes to "scale speed" I have attached a pic of a full size version of my boat that is fitted with a hot V8, so fast brushless models are not that outlandish when full size 80 year old Chris Crafts can hustle along like this old lady
Hope this is of some help
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Eddie W on July 26, 2018, 08:49:02 PM
Thanks for all the replies. Given me lots to think about.
Eddie
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: canabus on July 27, 2018, 03:05:18 AM
Hi Eddie
If you change to 4S Lipo you will turn it into rocket with that motor.
I have been down that path, well over the hot V8 speed !!!
Canabus
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Hotglove on July 27, 2018, 07:34:02 AM
Hi Canabus
Thanks for your original advice, as a novice boater the 3s is more than quick enough for me, but great to have such potent reserves in the tank.
Now happily learning boatcraft with my Robbe Turo L plate special RAF tribute (documented elsewhere on Mayhem)
Thanks again
Ian
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Eddie W on March 26, 2019, 01:36:51 PM
Due to family issues I didn't manage to buy the Turnigy 3639 or the 3648. They are both now out of stock. Has anyone got any recommendations for any other motors?

Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: shadysadie on March 26, 2019, 07:14:51 PM
How about a "Tornado Thumper V3" 3536/08 1050kv by Overlander. Runs on 2-4S Li-po and should give all the power you need on 3S. Alternatively, a "Thumper V3" T3548/05 900kv will prove more than adequate.
Title: Re: Dumas Chris Craft Triple Barrel Back running gear.
Post by: Eddie W on March 27, 2019, 07:15:49 PM
Thanks for the suggestion  :-))