Brutus

[Bob Abell 2Participant @bobabell2]

Paul

I would like to build this boat, just to see how it behaves on the water

It looks so unusual and is a useful size. I may have to buy a couple of larger motors etc to do it justice

I only need the salient points and skeletal details………

The workshop is tooling up for action!

Ashley,many thanks for your very kind PM and more congrats for your James Bond project in January's issue of the ModelBoats Magazine………And you said, you make them simple!

Paul's models will make a very interesting exhibit on the club stands next year?

Bob

[ashley needhamParticipant @ashleyneedham69188]

Bob. thats the idea. You only need a quick look and a few basic dimensions and off you go. Thats what I do anyway!

No point in making anything difficult if you can make it work simply. Will post vids asap. The lotus one is uncanny in its depth keeping (for a dynamic dive machine).

Pauls models need to be grouped together to emphasise the sameness of the hull and difference of the top.

Ashley

[Paul TParticipant @pault84577]

Bob

Very happy to renew the partnership with this new design, you will have to let me know what motors you want to use so that I can ensure that we have sufficient space within the model and that the drive angle remains shallow.

Paul

[Bob Abell 2Participant @bobabell2]

Hello Paul

You can select any motor/ motors you recco at this stage and we'll work from there……Twin motors would be more interesting

Let your imagination…..Run riot!

Bob

[Paul TParticipant @pault84577]

Bob

We will stick with a pair of 600s with the reverse drive system that we discussed before.

Paul

[Bob Abell 2Participant @bobabell2]

As already mentioned…..The flexible coupling as drawn is not required

In fact….It won`t work!……….LOL

Bob the Engineer

[Paul TParticipant @pault84577]

You're right Bob but it will work in a set up like this

I am now hunting for some small encapsulated bearings as can be seen under the mounting plate in order to design a bespoke set for Brutus.

Paul

Edited By Paul T on 10/12/2013 14:46:56

[Bob Abell 2Participant @bobabell2]

Just had a look on the net and discovered that the Axehead type of hull really exists and is a patented design!

So we`re "Hitting the ground running" As they say…..And off to a flying start

Here she is……

I like the hollow keel and the aggressive looking prow

Bob

[Paul TParticipant @pault84577]

Yes Bob its a design type that has fascinated me for some time but we are not exactly hitting the ground running as you will have noticed that the larger ships have quite a few stabilisers and therefore I have to assume that they suffer from stability problems.

Brutus has no stabilisers and relies on hydrodynamic design to maintain stability and I am having to be very careful where the main point loads are positioned, I expect that the finished model will need some very precise fine tuning at the lake side to get the trim right.

This is why I said that the build will a challenge to your theoretical skills as well as your building skills. Motors and batteries will have to be placed in exactly the correct position and any change in specification will result in a weight trade off somewhere else in the design. It will be very easy for the model to nose dive or for the bow to ride to high if the weight distribution is not precise.

Paul

[TelstarParticipant @telstar]

Hi Paul Your design reminded me of a model from my past. I finally found these photos of Tom Clements from one of the Newcastle clubs with his Straight runner.

It has quite a deep stem and I think it was powered by 4cyl T Westbury design engine (Sealion) driving twin screws the mechanism on the rear deck is screw adjuster for the twin rudders

Tom

[Bob Abell 2Participant @bobabell2]

Shop floor to Pie in the sky

We can make our own motor drive, as you originally laid out…..Don`t need the countershaft

I have noticed that our Axe Head is rather blunt, compared to the real thing!

We`ve got a cruiser shape, for some reason

How about a servo operated elevator at the rear to cancel out the Johnny Wiesmuller effect?

Just throwing a few spanners about

Bob

[Paul TParticipant @pault84577]

Bob

You know what happens when you start throwing spanners about…………..usually one or more end up in the machinery and it takes someone bigger than Tarzan to pull them out.

To answer your points one by one:

The motors wont fit without the countershaft unless I change the angle of the propshaft by increasing it beyond 8deg incidentally this would also raise the motors within the hull and compromise the centre of gravity,

Brutus has the same design profile as the full size ship, it looks blunt simply because its a speed boat as opposed to the super cruiser in your photos.

Theoretically the hull shape should work without having to fit trim tabs or elevators, notwithstanding the fact that their very presence would change the hydrodynamics of the hull and create more problems than they would solve….they look awful and would ruin the lines of the design.

Spanners are for tweaking nuts.

Paul

[Bob Abell 2Participant @bobabell2]

Tarzan hey!……AAAAAAAAAAaaaaaaaaooooooooooOOOOOOOOOOOAAAAAaaaaaaaa!!!!!!

Those were the days, hey!

I did say earlier…..Why not increase the prop shaft length and get rid of the belt drives?

The hull shape at the front doesn`t look sharp enough?

More to follow

Bob

[Paul TParticipant @pault84577]

Good Morning Captain Bob

Unfortunately increasing the tube length would have to go hand in hand with raising the height of the motors within the hull and this will change the centre of gravity making the forward section of the model unstable when making high speed turns.

This plan view shows the overall shape of the model

You can see that the prow is quite sharp and that the shape is further enhanced by the curve starting amidships.

 

Paul

 

Edited By Paul T on 11/12/2013 08:05:03

[Bob Abell 2Participant @bobabell2]

For some reason, I imagined a shape like a slice of cheese…..On edge…….Axe Head

You are the designer……..Carry on regardless

Bob

[Paul TParticipant @pault84577]

Bob

To get you started the minimum size for the Brutus building board is 1230mm x 380mm.

Paul

[Bob Abell 2Participant @bobabell2]

Building board size…….No problem

Ready when you are, Govner!, but will have to take second place to SloMoCruiser for the time being

Just had a right picnic with my password….OK now

Bob

[ashley needhamParticipant @ashleyneedham69188]

What a shame the top view does not look as futuristic as the side view!!

Bob, it needs some "ray gun" exhausts and rocket fins, or something when you start…..

Ashley

[Bob Abell 2Participant @bobabell2]

Ashley?……..Exactly!…..Leave it to me

But Paul won't like it!

Bob

[Amy jane SeptemberParticipant @amyjaneseptember49770]

Yeah, this is getting interesting….

[Bob Abell 2Participant @bobabell2]

I suppose the outlandish deck line will give it the desired quirky look?

Plus a couple of stubby wing things…..I also like the shark type trim tabs down below

"That`s the way to do it!"

Mr Punch

[Paul TParticipant @pault84577]

Don't forget to allow for two coats of emulsion whilst doing your quote for re-decorating the Sistine Chapel

Philistines

[Bob Abell 2Participant @bobabell2]

I knew you would approve, Paul

What about a Nautiius type of jagged teeth shape, on the prow?…….That's it!……..The lost chord?

That'll warm yer cockles!

Mr Punch

[Bob Abell 2Participant @bobabell2]

Paul……Just had a brill idea!

If we need bigger motors for Brutus, then get them now and fit them in the SloMoCruiser!

Drawing Office to advise the ideal motors, please

Bob with his WW2 goggles on already!

[Paul TParticipant @pault84577]

Bob

Have you ever heard the term 'less is more' ?

The Brutus design doesn't need embellishments such as grinning dentures, painted flames, rocket exhausts, furry dice or any other boy racer additions nor does it require machine guns, lasers or a warp drive.

The ideal motors are still a pair of 600s

Paul

Edited By Paul T on 13/12/2013 14:51:32

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