Vintage Gentleman’s Cruiser

[Bob Abell 2Participant @bobabell2]

Paul is alway's the Joker

What a lucky find hey?

However……..Curly Dave have given me an idea!…….

I've got dozens of electic plug brass things that I can make good use of!

I'll be back in two ticks!

Bob

[Bob Abell 2Participant @bobabell2]

Decided to leave the sprockets as they are at the moment and get on with the construction

We need to see how the two motors behave in unison

Here`s a WIP picture, for interest and any comments?

This drive will be tried out in the Ellie launch

The prop shaft will be on the chain side for accessibility and appearance

Bob

[ashley needhamParticipant @ashleyneedham69188]

Bob, Wont this be a bit noisy??? all that plastic flapping about?? Ashley

[Bob Abell 2Participant @bobabell2]

Don't know myself, Ashley

I'm hoping it will sound "different"

It will also act as a sort of gearbox too…With either one or two motors powered up

MK11 will have proper timing belts

We like to experiment with new ideas…..It keeps us young!

Bob Young

[Dave_PParticipant @dave_p]

Hi Bob,

Not sure if I'm correct but if you only power one motor the other will become a dynamo and if connected to a circuit may cause problems?

I may be wrong and will stand corrected by others in the know. I am more of a pistons and oil man by trade than a lectrickery type.

Dave

[Bob Abell 2Participant @bobabell2]

Hello there, Dave

You could have a point there?

That's the beauty of this exercise!

Pioneering the unknown!…..It might even charge the idle battery up!

Bob

[Dave_PParticipant @dave_p]

Or you could have an inbuilt one use only smoke generator

Dave

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Hi Bob, How's this for a timing belt?

From a defunct printer.

[Bob Abell 2Participant @bobabell2]

Here's a good source of timing belts and sprockets….

Bob

[ashley needhamParticipant @ashleyneedham69188]

I have seen other twin-motor drives, one in a v large Severn, and no mention was made of imbalance between the motors. I think there will be no problems but a check on each motor with an ammeter may be in order when loaded in case.

Those belt drives are expensive or were last time I looked. I like the chain, looks more "mechanical"

Ashley

[lnvisiblemanParticipant @lnvisibleman]

Bob etc.

I may be wrong here so jump in if I am.

All that will happen if there is an imbalance is that one motor will want to rev faster than the other. That will cause the slower motor to be under less load and consequently it will run faster. The net effect is that both will run at the same constant speed with no problems. All that will be found is that one will draw less current than the other.

Mike

Mouth open waiting for foot

Edited By lnvisibleman on 06/07/2014 09:33:31

[Dave_PParticipant @dave_p]

I agree with you Mike but my point is if you are only applying power to one motor what is going on with the other. If you spin a dc motor shaft I am fairly sure it will behave like a dynamo and produce a voltage at the terminals. What effect this will have on the esc I don't know.

Dave

[lnvisiblemanParticipant @lnvisibleman]

Dave

I totally agree, it essential that both motors are working and not just one under power or the unpowered motor will certainly act s a dynamo.

Are we looking at perpetual motion here ????

Mike

[Dave MilbournParticipant @davemilbourn48782]

Posted by lnvisibleman on 06/07/2014 10:53:42:

Are we looking at perpetual motion here ????

Mike

Could be. After 21 pages it's showing no signs of slowing down yet………………..and no-one seems to have picked up a glue bottle thus far.
DM

Edited By Dave Milbourn on 06/07/2014 11:33:16

[Dave_PParticipant @dave_p]

OK I can take a hint

[lnvisiblemanParticipant @lnvisibleman]

Posted by Dave Milbourn on 06/07/2014 11:32:42:

Could be. After 21 pages it's showing no signs of slowing down yet………………..and no-one seems to have picked up a glue bottle thus far.
DM

I will do if I get the plans !!

Mike

[Diede van AbsParticipant @diedevanabs87670]

Concerning the two engines on one propshaft: No problem at all, it has been done before even on commercial units (such as the Hydrospeed drive as featured in the Graupner Systems cat, with two Speed600's).

Powering only one of the two engines is a huge waste of energy, as this one engine is now powering both the propshaft and the second motor, which in turn effectively acts as a nice mechanical heating mechanism. With the added hazard of overloading the powered engine, too…

Edited By Diede van Abs on 06/07/2014 14:49:52

[Bob Abell 2Participant @bobabell2]

Steady on there, Diede

I won`t be running one motor intentionally

The greatest danger is going in reverse on one motor!………Then the sparks will fly!

We are just experimenting at the moment and messing about

Bob

[Paul TParticipant @pault84577]

Bob

We should explain that whilst you are experimenting with twin motors I, as DM has surmised, am dabbling in the warp drive capabilities of perpetual motion all on the basis that if I'm going to break a law then it might as well be a serious one.

At the moment I have managed to compress all of creation into a very small space and the creation of a stable warp field is within my reach…..but unfortunately I have lost the key to the very small space so now all of reality hangs in the balance…………so I am off to the pub.

Paul

[Dave MilbournParticipant @davemilbourn48782]

Are we paying for these tablets or do you get them privately??

[Paul TParticipant @pault84577]

Dave

Good old NHS…. you are free to go barmy without worrying about running up a big bill.

Paul

4650 hits and I've still not picked up a glue pot

 

Edited By Paul T on 06/07/2014 18:47:22

[Diede van AbsParticipant @diedevanabs87670]

Bob – if two motors running against each other cause sparks over there, then either you are doing something VERY wrong while doing something very wrong. You should not run them against each other in the first place, obviously, but even IF you did that, then either your chain should snap or the motors would both stall and heat up until smoke was emitted heralding the tragic death of two brave E-motors.

Sparks IMHO mean that your wiring is so bad that it is coming loose, creating spark arches….

Paul, ask your wife – maybe she knows where you put that key of yours.

Either way, the rule you are breaking on the perpetual motion thingie with two motors, is the one that says that the power input into a system equals the power output – and friction resistance caters for a bit of power output in the form of heat. Thus slowing the motors down until all power has been lost to the surrounding.

Oh, and of course, if you have two engines wired up in parallel, which is sort of mandatory for this kind of experiment, and you power one of them – the second one will be powered as well, per definition of copper wires

[Bob Abell 2Participant @bobabell2]

Diede

My transmitter is an F14 with two throttle sticks and if they are not used in perfect unison, the motors could accidentally be opposed, when the model is on the pond, as it won't be obvious then, that something is wrong, until blue smoke starts to appear!

To safe guard against this, the sticks will be bolted together

Thinking about it even further……..When the sticks are in neutral, there is the danger of slight motor opposition still taking place, as equal zero's will be hard to achieve

I will have to give this matter some serious thought!……Mmmmmmmmmm….Zzzzzzzzzzz

Bob

[Diede van AbsParticipant @diedevanabs87670]

Bob – Having two separate channels and separate ESC's for motors that are mechanically coupled just makes no sense at all.

Either use one beefy ESC for both motors at the same time (which I would highly recommend), or if you really insist on having two ESC's use a Y-lead on the wire between ESC and receiver to keep them synchronous.

Tying your twin stick together is penny wise, pound foolish outright stupid. One day you'll forget to tie them together after using it for another boat, and then you'll end up without magic smoke after all. Just make the solution in the boat fool proof, and you'll be fine.

Edited By Diede van Abs on 07/07/2014 12:43:42

[Bob Abell 2Participant @bobabell2]

Diede

If I use a "Y" lead….Will it guarantee equal zero`s on both sticks?

I doubt it

The ESC`s need to be set up with Zero and Max positions independently and then paired up…..eh?

Deepest sympathy regarding your footy team

Bob

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