Brutus

[ashley needhamParticipant @ashleyneedham69188]

Young man, thank you Bob.

I dont normally have an issue with the gear, its the running of the model on the water that is generally the problem.

The next mag one has taken I dont know how many small and big mods, changes of gear, batteries, drive, you name it. I have cut,sanded,added,taken away, filled. It has been a right palaver.

Although we all have our opinions (especially at the pond) of how Brutus will perform, it will of course perform ok. There may be a few small tweaks required, bound to be, with a new design, but it will eventually be a bung-it-in-the-water-and zoom off affair. .Trust me.

Ashley

[HowardParticipant @howard79726]

Gentlemen

I find this all rather familiar and heartwarming in a perverse way. We put what might seem disproportionate time and effort into a project that may at first underperform at the pond. We bring it home, stand it on the bench and glower at it or studiously ignore it for several days, then start tweaking, modifying, swapping bits (in my case with a lot of help from this forum) until, as Ashley says, it runs perfectly. Surely every model is a prototype, more or less, and getting it to work properly is a major part of the fun. Thanks to Paul, Bob et al for sharing this project with us. I'm sure Brutus will soon be running nicely, and I'm looking forward to the pics!

Howard

[Bob Abell 2Participant @bobabell2]

Hello Howard

Thanks for dropping in and your constructive comments are always welcome

The ESC has some intelligence built in and can easily be scrambled by the Newbie!

At one point, I had both props operating from one tranny stick, so there is some interference somewhere

The expert did mention that getting twin motors to run together is not that easy……Probably due to interference?

I suppose my constant ramblings are a bore at times, but must be useful to some people?

Please call again

Bob…..With Paul in the wings

[Bob Abell 2Participant @bobabell2]

Hello Howard

Thanks for dropping in and your constructive comments are always welcome

The ESC has some intelligence built in and can easily be scrambled by the Newbie!

At one point, I had both props operating from one tranny stick, so there is some interference somewhere

The expert did mention that getting twin motors to run together is not that easy……Probably due to interference?

I suppose my constant ramblings are a bore at times, but must be useful to some people?

Please call again

Bob…..With Paul in the wings

[Bob Abell 2Participant @bobabell2]

Here we go, Paul

We are back in the land of the living, having scrapped those troublesome Brushless things in favour of two MFA RX15 Plus RE 700 Brushed motors

Might have a problem fitting them in, since the Blushless motors were so small

Bob

[Paul TParticipant @pault84577]

Bob

I will look at the design and rejig it to suit the MFAs as there will be a weight distribution issue.

Paul

[Paul TParticipant @pault84577]

Bob

The problem will be the vertical position of the new motors in relation to the brushless motors.

To keep the prop shaft angles shallow the brushless motors were fitted very low in the hull, removing the brushless motors will leave the C/L of the propshafts too low.

I think that the only way to link the MFAs to the propshafts will be to use a belt drive (like below) essentially the motors have to remain in the same bay between F4 and F5 and be as low as possible

Sorry the drawings are a bit scruffy but I will tidy them up tomorrow

Paul

Edited By Paul T on 31/05/2014 20:26:21

[Bob Abell 2Participant @bobabell2]

Shop floor to Drawing office

There may just be enough room to get the motor in….I won't know for sure until the motor bracket arrives

The ideal chance for TurboCAD to shine!

Bob

[Bob Abell 2Participant @bobabell2]

Hello Paul

The brushless motor is 24mm from shaft centreline to the base and the MFA motor is about 40mm dia

So that leaves 4mm to get the bracket in

I also have another trick up me sleeve……For emergencies

Don`t forget….I`ve only got two weeks to the show

I`ve sorted out the radius question and the ortho and offset questions

Bob

[Paul TParticipant @pault84577]

Bob
The centres are 11mm adrift and you also have the curve of the hull at that point that will add another 5mm to the misalignment.
I would suggest that an easy way to achieve the alignment would be to invert mount the motors (suspended the motors and mounts upside down from a frame)
Paul

[Bob Abell 2Participant @bobabell2]

Don`t forget my Artist`s licence!

We`ve got enough room

See here…..

Bob

[Paul TParticipant @pault84577]

Captain Bob

I had forgotten about your 'Artists Licence'………did you make the space larger or fit the prop shaft at a steeper angle?

Paul

[ashley needhamParticipant @ashleyneedham69188]

That Bob is a right artist!! will the geared motors spin the props fast enough??? i am not familiar with the chosen motors. The offshore boys use solid steel couplings of the ball and pin variety..would these be short enough to permit direct drive (and suffer small misalignment?)

Ashley

[Dave MilbournParticipant @davemilbourn48782]

No gears here, Ashley **LINK**

Dave M

[Paul TParticipant @pault84577]

Bob

Would you like to build this

Paul

[Bob Abell 2Participant @bobabell2]

Not at the moment, Paul…..Can't make out the superstructure. It's well camouflaged

Looks like a variation on Brutus?

Bob

[Paul TParticipant @pault84577]

Yes it a variation on the Brutus build and will be very impressive on the water………..if only I could convince someone to build an 8ft model.

I tried to design it around hardboard just to get 'you know who' interested but the strengthening required was phenomenal (I really wanted to see 'he who should not be named' get it to the lake on his bike)

[Bob Abell 2Participant @bobabell2]

You are being extremely flippant tonight, Paul

Nice to see you back

Bob

[ashley needhamParticipant @ashleyneedham69188]

i am thinking of a nine foot DUKW, with working wheels, out of that unnameable substance, and then I would not have to use the bike..

Ashley

[Paul TParticipant @pault84577]

Ashley

A 9ft model would be something worth seeing and it would make a fine sight as you drive around the Dianna memorial in your big yellow duck, you could have wheels where the flippers should be and sit inside just behind the neck. As you pedal along the beak could be made to open and close by fixing a drive belt to one of the rear wheels.

Being made from hardboard would also be an advantage if you were ever hungry as, with just one match you would have almost instant crispy fried duck.

Its a good idea and not as quackers as it sounds.

Paul (looking for my marbles)

[Bob Abell 2Participant @bobabell2]

Hello Paul and chaps

Finally got the new motors and ESC`s for Brutus and they look as though they will fit OK!

Both the motors and ESC`s come complete with wiring, plugs and capacitors…..Luxury!

Will be making special solid couplings to fit the available space

Bob

[Paul TParticipant @pault84577]

Doesn't it look small inside that cavernous space

[Bob Abell 2Participant @bobabell2]

It does look rather small?…..According to the blurb, they are smaller than usual, but with extra "variable" power?….What ever that means?

Will have to keep our fingers crossed till we have the proof of the puddin`

I think they will be ok……..Brutus is just a lightweight empty box!

Full of …….Hot air!

Bob

[Paul TParticipant @pault84577]

Bob

Variable power? Don't all motors have this capability

Paul

ps Jane says the boat is just like the designer….full of hot air

[Bob Abell 2Participant @bobabell2]

Read this, translate and report back, please…………..I know somebody who will have something to say about it!

**LINK**

It`s got adjustable timing of some sort?…..Haven`t read the blurb yet

What a good job we fitted the cooling fans, eh?

Bob

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