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[trelawney]

Model boat 30 inches long , 5 inch beam . Wood construction - not balsa.


Would welcome advice on a suitable electric motor and radio control gear  please.

Thanks

Trelawney

[Colin Bishop]

I think you need to tell us what type of boat it is.

Is it a fast power boat, a sedate scale boat or whatever? Displacement hull or planing? Method of construction is not really relevant to propulsion as displacement will be the same regardless.

Colin

[dodgy geezer]

How much of a beginner are you to radio control?  Flyboys can usually use their aircraft kit, so long as it's 2.4GHz. If you have never used a radio before you will be ok with most 2.4GHz units. And have you thought about where you are going to sail it...?

[trelawney]

Thanks replies.Celia May on the Sarik Hobbies site.
I would think a sedate non scale boat,  perhaps best described as a cabin cruiser?
I know nothing about radio control.

[GordonB]

Google around to see if there is a club near you. They will know where to sail and recommend suitable kit. You might well get second hand kit from a club member. Bu basically you need a transmitter, a receiver and a speed controller (ESC) plus a servo for the rudder.

[dodgy geezer]

Do you have a budget?


It's a good idea to attend a local club day and chat to some of the members - they will show you what you need and advise where to get it.  If you can't, you will probably be well set up with a 2.4GHz set - don't  look for a 27, 35 or 40 Mhz system which are older standards but may still be available second hand.


At a minimum you will want the radio to provide 2 control functions - rudder and speed. These are often called 2 channel. Aircraft need 4 channels, and their radios look like a box with two sticks coming out. While cars and boats often use these, they can also use simpler 'pistol-grip'' transmitters which look like a gun grip with a steering wheel attached.


Whichever you pick, there are broadly two cost bands. Cheap ones are about £20-£50, more sophisticated ones are about £80-£200. The cheaper ones are fine for a beginner.


When you buy a 2.4GHz radio control set you should at least get a transmitter and a matching receiver (often called a combo). Usually one brand of 2.4GHz radio transmitter requires its own matching brand receiver. As well as the 'R/C combo', you will also need a servo which attaches to the receiver and moves to turn the rudder when commanded, and an Electronic Speed Controller (ESC) which attaches to the receiver and provides power to the motor. Servos and ESCs do not have to match the radio brand, and often (usually!) don't.


There are two main types of motor, brushed and brushless. Brushless are typically more powerful, though a bit more complex. The ESC must match the motor - a brushless ESC will not control a brushed motor. Brushed would be better for you, they are usually easier to mount in a boat and their speeds are more boat-compatible. Have a look at the MFA Torpedo 800 or 850...


You will also need a battery pack. Again, there are two main types which you might consider, NiMH or LiPo. LiPos are powerful and light, but need more complex care and a specialist charger - you would be better off with NiMH and a simpler NiMH charger.


A good approach would be to choose your boat, then pick an appropriate motor. That will decide what ESC you should buy, and at that stage you could pick your radio set...

[Subculture]

"a brushless ESC will not control a brushed motor"

Some can control both.

[dodgy geezer]

"a brushless ESC will not control a brushed motor"

Some can control both.

I'm trying to cover a lot of ground simply. There are going to be exceptions to practically everything I said above...

[Circlip]

But don't forget Dodgy, he might want the capability to control fifty different models with 200 switchable functions and posses an  honours degree in advanced computer science. 


  Whatever happened to the Sanwa mini two or the Fubarta three?


 Regards  Ian.

[philk]

Where abouts in the south West are you hopefully can find you a local club

[roycv]

I have a Celia May from the Sarik plans.  Not much power needed.  If you use a 5 pole 6/7 volt 385 or a speed 400, motor, not the 6 -15 volt one, and a stick of 6 Nimh cells giving 7.2 volts it will go nicely. 
I use the very cheap and tiny bandolean electronic speed controls from AliExpress at about £2 each!!  Yes, £2 or less each!  They have a tiny switch on them for disabling the resistive breaking so you get immediate reverse.
 I buy enough to cover the minimum p&p.  They work fine, the maximum current I use on other models is 4 amps and never had a failure.
You will need to buy some ready made 2 pin leads  but these are very cheap as well, get male and female for just a couple of pounds.
With electric motor power etc, I elected to make the deck removeable with the superstructure in place.  Otherwise as designed it can fall off and sink as it is aluminium.  If you look carefully at the plans you will see that there is a rim around the deck which the deck fits into.
Good luck
Roy

[roycv]

Hi again my Celia May (above) is running on a vintage Bassett-lowke Marine motor a Mabuchi 55 would suit.  I use vintage RC this is an old Hitec 2 channel radio, I still use the old stuff as I have nearly 20 radio sets so not worth me updating to 2.4Ghtz.

You will need to solder on 0.1 microfarad capacitors, 3 for a motor.  One capacitor across the brushes and the other 2, from each brush to the metal body of the motor.  That will get rid of radio frequency interference.  It may not be needed for 2.4 Ghtz but it will upset anyone running with the previous frequencies.
Do not over-think it, you only need 10 Watts of power, reduce propellor size to give 1.5 amps max.

  You might give some thought to bending the forward part of the hull, I used a constructed steam chest and used 9 ply plywood I suggest you avoid that!  Use 3 laminations of 3 mm bass wood or obechi, this will make the upper rim easier to construct.  Steam them onto a jig it can be quite crude, long nails on some deal or pine.

The steering is off the stern formed with a sawn 2 inch Meccano pulley and chain as per old tug boat system.

Good luck
Roy

[dodgy geezer]

Looks like an 800 would be over-egging the pudding, then, if a 400 would be satisfactory. I was thinking of sufficient power to plane. 

[dodgy geezer]

...and the Celia May looks vaguely like a Streamlinia...

[roycv]

Hi Dodgy The Streamlinia is next size up at 40 inches or in Euro-speak 1 metre.
I have made a Streamlinia but chose not to carve from the solid!  I have copies of the plans published in the Hobbies Annual 1937.  I re-drew plans for a frame and ply construction which was easier to make. soit got rid of a fault with the hollows at the bow, which had her dipping her nose.  I also fitted spray strips, ever hopeful!

There were several s/s's to choose from, I chose the post-war RC model available in the late 1940's for £45, which was a lot of money. 
My one started with a compact twin cylinder D/A 3/8ths bore and stroke engine.  It was on long loan from M. Beak who designed and built it.  It had our joint design of boiler water level automatic control, this was 1988, and this was later added to to give a control of gas burner when full pressure was met.

The boat would plane for 15 seconds while maintaining 30 lbs pressure, but then dropped off.  I built my own rev counter and with that and a Meccano constructed dynamometer, we calculated the power of the steam plant.  This revealed that a 2 inch 3 bladed brass prop spinning at 2000 rpm would indeed get her to plane.

The steam plant was removed and a 550 size 5 pole motor installed driven by 2  off 6 volt SLA's  giving 12  got her nicely up on the plane and she looked good.  As a bit of a leg pull I used a gearbox a friend had made for me with some plastic tubing and power transistor insulators and a plastic 'boiler' to cover the batteries to simulate a turbine, it fooled quite a few people!

I was not using her much and a fellow club member who was going to build the boat and the steam plant opted to buy the model from me.  Some years later a genuine B.L. Streamlinia was shown at a regatta with original steam plant they were in the water together and the original just pootled along nothing like the adverts.

I found out later that the RC B.L. version had their own Marine electric motor and by chance the photo of The Celia May, a copy of the commercial Sea Jay has that very same motor and you can see it suits her well.
Sorry to go sideways on this thread but I do like the old toy boats.
Roy

[roycv]

Hi all, re my suggestion on esc's.  Aliexpress has 10 amp upto 8.4 volt i/p speed controllers for £0.75p  that is what I call a budget buy!  I use them and they have worked for me with the last half dozen boats I have made. 
Your choice but in my case with just pension income the choice was easy.
Roy

[Dave_S.]

Hi Roy, as a fellow pensioner, I am always interested in a bargain, but I couldn't find the ESCs you referred to on Ali Express - any chance of a link?


Thanks, Dave S in Oxfordshire

[Subculture]

These? https://www.aliexpress.com/item/1005006112400103.html?spm=a2g0o.detail.pcDetailTopMoreOtherSeller.2.25651a95Q6g3tz&gps-id=pcDetailTopMoreOtherSeller&scm=1007.40050.354490.0&scm_id=1007.40050.354490.0&scm-url=1007.40050.354490.0&pvid=d1729c80-d29e-4d00-9668-256112b13784&_t=gps-id:pcDetailTopMoreOtherSeller,scm-url:1007.40050.354490.0,pvid:d1729c80-d29e-4d00-9668-256112b13784,tpp_buckets:668%232846%238114%231999&pdp_ext_f=%7B%22order%22%3A%22206%22%2C%22eval%22%3A%221%22%2C%22sceneId%22%3A%2230050%22%2C%22fromPage%22%3A%22recommend%22%7D&pdp_npi=6%40dis%21GBP%217.43%210.76%21%21%2167.75%216.86%21%40211b61bb17672789393652717efe45%2112000035803319377%21rec%21UK%21%21ABXZ%211%210%21n_tag%3A-29910%3Bd%3A9cc6d374%3Bm03_new_user%3A-29895%3BpisId%3A5000000187686197&utparam-url=scene%3ApcDetailTopMoreOtherSeller%7Cquery_from%3A%7Cx_object_id%3A1005006112400103%7C_p_origin_prod%3A

[Circlip]

Wonder how many items from these sources are going to be crippled by the new import taxes? 


  Regards Ian.

[Martin (Admin)]

You're right Ian, many AliExpress prices are stupid high now when exporting to UK  ... import TAX added... 

 But some items can be found, same item different seller, or shipping method.
 
 

[roycv]

Hi Subculture they are the ones I use they work very well.  When I first used they they were less than a pound each but never been over £2.  I know they sound too good to be true but they work do not get warm in use.  The only extra I would add is to get some of the 2 pin wires M & F which are equally cheap.
Roy

[Martin (Admin)]

Also on Ebay, UK ....
( check shipping location for ETA )

eBay item number:317651881525

eBay item number:286491460577