another Barrel back launch

[Bob Abell 2Participant @bobabell2]

Congrats….Phil

 

But straightaway, it doesn`t look quite right without a driver?????

 

Bob

[Phil Winks 1Participant @philwinks1]

I totally agree Bob and an ensign/pennant but those Items are waiting till I go to the weymouth festival in July 8″ figures seem non existant on the web nearest I’ve found are 1/12th and at 6″ they’re just a little too small I feel really want something at 1/8th

[Paul TParticipant @pault84577]

It looks great on the water and I am very pleased with the way it reacts to the radio commands.

I really like the way the clean lines haven’t been ruined by a scarecrow barbyman.

 

My version of the video ended to soon as the credits hadn’t fully run before clip finished

 

Paul

[ashley needhamParticipant @ashleyneedham69188]

Phil. Grand job, and very reasonable performance on the water. I must agree with Bob.needs a driver. How about biting the bullet and MAKING one? you never know until you try!  Ashley

[Phil Winks 1Participant @philwinks1]

Sorry to hear  that Paul and I must apologise for not putting the Designers name in the credits something I will rectify immediately.  It does react very well to radio commands and looks the business on the water love the wave slapping as I pulled a tight turn and crossed its own wake. I’ve added 1/2 a pound of lead at the stern and made a cooling plate for the ESC so next outing could be even better fingers crossed. As for making a figure Ashley not a chance already tried some years ago awfull results honestly. Mind you thinking on I do have a friend who’s an artist and sculptor so maybe a good realistic figure isn’t so impossible to find.

 

Remix Video Specially for Paul

 

Edited By Phil Winks 1 on 19/06/2009 09:10:53

[Bob Abell 2Participant @bobabell2]

How about a simple black coloured profile………………….until you find something more suitABELL?

 

A profile is a doddle……………..could even be your goodself?

 

 

Bob

[Phil Winks 1Participant @philwinks1]

Had her out on the water Sunday with the trim moved sternwards and a much more pleasing performance at speed. No vid I’m afraid no one available to use the camera. Stll have an issue with the esc despite a cooling plate so I’m just going to have to spend £30 and get a second

[Phil Winks 1Participant @philwinks1]

Had her out on the water Sunday with the trim moved sternwards and a much more pleasing performance at speed. No vid I’m afraid no one available to use the camera. Stll have an issue with the esc despite a cooling plate so I’m just going to have to spend £30 and get a second

[Phil Winks 1Participant @philwinks1]

Hopefully I’ve sorted the esc overload issue I’ve fitted 2 80amp items and given that each motor is pulling about 27a each in a tethered run at full throttle they shouldn’t be worked to hard. I’ll prob get her back on the water tues or wed so we’ll see how it goes and we’ll see just how long those bty’s last my best guess is about 10 mins of mixed motoring

[Phil Winks 1Participant @philwinks1]

Had some water time with the Barrelback this afternoon and what a marked improvement there is the battery lasts about 25/30 mins and with the addition of another ESC and some forced air cooling for them not a suggestion of overheating. The addition of said forced air cooling has required a change to the air intakes/exhausts on the rear deck, to make them functional and big enough to be effective. This worried me a little but the end result is actually quite pleasing. Hopefully it’ll be out again Sunday as will the camera/camcorder.

[Bob Abell 2Participant @bobabell2]

Hello Phil

 

Are you still using motor drive…….as shown on your first page?

 

Bob

[Phil Winks 1Participant @philwinks1]

Hmmm No Bob there where problems with keeping lubrication on the gears and not all over the inside of the hull also it was sooooo noisy so now I have two tuned 19 turn 540 size car motors with a water tube wrapped around them. Must remember to get these snapped when the camera is out tomorrow

[Bob Abell 2Participant @bobabell2]

Now!……What did I tell yer?

 

But you can tell me about about your tuned motors……something new to me!

 

Bob

[Phil Winks 1Participant @philwinks1]

Basically standard 540 motors have 27 turns on the armature, and if you reduce turns you trade rpm for torque. However to get some of the torque back these have higher power magnets, and higher density rotor core. In simple terms these are a high performance 540 can motor with replaceable brushes, and are strip-able to allow the commutator to be trued up on a special lathe, thus extending the life of them. Some even have a facility to adjust the timing of the com’s relationship to the stator. another bonus is many have condensers built in to suppress rf noise and protect the brushes. Having said all this, in the car racing world these motors are fast becoming obsolete, courtesy of the brushless generation. My particular examples are turning a 40mm prop and barely breaking a sweat, both are working at about 75% of their max capability. They are 19 turn so still have good torque, but some of the motors available go down to 8 turns. Which gives massive rpm, and in a car with all its gearing, great acceleration/top speed. But in boats I suspect inadequate torque for all but tiny props, without a massive reduction in the gearbox. Having said all that the main reason I used them was that they were in my shed doing nothing else, and had they proved inadequate replacements would’ve been purchased.

Edited By Phil Winks 1 on 04/07/2009 21:56:56

[Bob Abell 2Participant @bobabell2]

Thanks for the info, Phil

 

I`ll probably go the brushless route

 

Just laid out the first former fo Slo Mo and it`s enormous at 23 ” ………needs another think I think!

 

A boat this big needs a big performance………….and I`m not sure I can get it!

 

 

That`s life!………………..Bob

[ashley needhamParticipant @ashleyneedham69188]

Bob, I think the brushless route may be the way to go for that but you would need to chat to a specialist. A lot of the motors appear to paired to LiPo batteries, and they come in odd voltages. It beats me.   Ashley

[Bob Abell 2Participant @bobabell2]

Luckily……………..We have just the said person in our club.

 

He gave the club members a very interesting talk recently……………..and it did seem a new avenue of thinking!…………………….and I`ll probably end up the wrong street!

 

Bob

[Phil Winks 1Participant @philwinks1]

I have been using brushless and LiPo bty’s in aircraft for about 2 years now lads and to be honest there really is no mystery. some slight differences but thats all. simply LiPo btys come in multiples of 3.7v and often the supply voltage of brushless motors is described as xs where x is the number of cells and s indicates that they are in series. if you wish to use bty’s other than LiPo simply use whatever you want that falls within the motors range for instance a motor whose supply v is shown as 2/4s will run on anything between 7.4v and 14.8v which is approx 6 to 12 Nimh cells obviously you need a specialist ESC and always overrate this item for safety also to make life easy brushless motors have a Kv rating which for the uninitiated means revs per volt so a 1000kv motor running on 12v should give 12000 rpm this is a no load spead so it will be lower with a prop on in the water. anothother advantage with brushless is the out runner motor where the rotor is outside the stator so giving the same diametre motor a much higher torque. so bigger  more efficient props can be spun without the need for gearboxes also the attrition rate of these motors is incredibly low no brushes to wear out and mostly they are ball raced, even the cheap ones.

 

Hope this answers more questions than it raises.

Phil

[Bob Abell 2Participant @bobabell2]

Thanks Phil……………….I`ll be taking more notice nearer the time

 

Unfortuneately, my Slo Mo posts are now spread over a few threads and it`s a bit hard to keep up to date

 

Bob

 

 

[ashley needhamParticipant @ashleyneedham69188]

Phil, I may print your post and have it handy for reference later on, as I have a ….Project on the boards which needs something more in the way of power but small with it, which is where these brushless motors score. Ashley

[Phil Winks 1Participant @philwinks1]

Glad I could be of some use Ashley This has made me think that maybe I have a little expertise here thats not so common within the model boat world perhaps enough to spend my copious spare time penning a “rough guide to choosing a brushless motor” for the members contribution section wonder what colin thinks of that

[ashley needhamParticipant @ashleyneedham69188]

Excellent idea!!! The model boat world (in general) doesnt have this expertise as it (generally) doesnt need it. Boats have the size and weight carrying capacity not to be bothered too much with this sort of technology. BUT now and again, its useful….   Ashley

[Paul TParticipant @pault84577]

Hi Phil

You should defiantly write it, speaking for myself such a piece would certainly help me as I know nothing about brushless motors and LiPo batteries.

 

I do know that Colin is very keen to have more articles written by members for inclusion in the new Member Contribution section.

 

Paul

[Phil Winks 1Participant @philwinks1]

Ok Chaps I’ll get on with it just one piece of info that I will need is some sort of guidance to what size prop is suitable for what brushed motors that way I can work out what sort of prop size will likely work best with individuall brushless. Direct drive will do as all I need is an indication as to what sort of load a particular size of prop applies to a motor. I can give a guide without but this info would make it more accurate

 

Phil

[Phil Winks 1Participant @philwinks1]

This post is for Bob. as promised some pics of the final motor setup. Basically twin 540 brushed motors from 1:10th touring cars each with its own esc only one of which supplys the BEC current. also they show the modified cooling air inlet/outlet and the rather large PSU fan pressed into service to ensure a good airflow at low speeds.

 

Edited By Phil Winks 1 on 19/07/2009 19:48:40

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