Brutus

[Bob Abell 2Participant @bobabell2]

Got an nice idea for a paint job, Paul…..Of course you won't like it!

A section of the Union Jack, with the middle section starting at the front, with the rest of the flag design, streaming behind. Will do a PS job

Got the paint today from….Barmouth! Just black and white, I'll mix my own greys

Had a nice day out in the Sunshine

Bob

[ashley needhamParticipant @ashleyneedham69188]

Bob.It`s no good, I shall have to put you on my "hate you forever" list for being v mean.

Was Paul suggesting the we had some rationality to start with??

Satin Black can look nice , not as severe at matt, but a bit more mysterious than gloss.

Ashley

[Paul TParticipant @pault84577]

Bob

That style of union jack has already been done in fact I can remember seeing it on a corvette at the rainy city custom car show back in the mid 70s and more recently on a hovercraft featured in Model Boat magazine.

Ashley

Look in the dictionary for the antonym of Model Boater and you will find the word 'rational'.

[ashley needhamParticipant @ashleyneedham69188]

Paul. I should have to look up ANTONYM first,.

I thought the featured hovercraft in MB looked quite fetching in a Union flag, if a bit gaudy.

Ashley

[Bob Abell 2Participant @bobabell2]

Went to the DIY shop and couldn`t get two shades of gloss grey

So, I got a tin of white and a tin of black……Which turned out to be a great idea!

Because I was able to mix my own two shades that looked just like Paul`s colour requirements!

I abandoned the Halfords spray paint idea………Too anti social for indoors!

Bob

[Paul TParticipant @pault84577]

Admiral Bob

The 'red oxide' has helped show off the curves and I am very happy with the way that the chine just melts into the bow.

Looking at that immense lower hull planing area I am more worried about how skittish this model will be and how difficult it will be to turn at high speed, which reminds me, when its complete I will give you a little infra-pink lizard emblem trade mark for the engine cowling.

Paul

[Bob Abell 2Participant @bobabell2]

Thank you, Paul

The propshafts have turned up and I`m in the process of installing them right now

For the benefit of the readers, this is my preferred method…….

I make a template for the motor end and one for the propeller end, with the propshaft centres drilled and with a central feature, like the keel, to centralise the fixtures

Motor template

Note central location. This template will be glued in position permanently

Packers will be made to align the motor axis and glued in position

Bob

Propeller template with central location

[Bob Abell 2Participant @bobabell2]

Question……..

Are we supposed to grind flats on the motor shafts for the grub screws to drive on, or do we rely on the grub screw acting as a clamp?

A flat on the motor shaft may upset the high speed motor balance?

The same applies to the prop shaft

Bob

[Andy CParticipant @andyc56856]

Hi Bob

Found the answer to the Health and Safety bods.

I think they might see this paint job coming and keeps to the general scheme of things.

andy

[ashley needhamParticipant @ashleyneedham69188]

Bob. As you are dealing with a modicum of power here, I would say that a flat on the shaft may be a good insurance against slippage.

Dont recall seeing many flats on motor spindles, but this may be more due to bumping up production costs rather than necessity, what size are the shafts?? if they are a reasonable size I should think a small flat would be good, cant imagine upsetting balance too much. I have seen motors wit flats on now and again.

Looking very good Bob. A bit of paint to make everything uniform always works wonders, Trouble is you will see all the little high and low spots and cracks etc now and have to get the filler out! I dont suppose this will amount to much in your case due to the superb workmanship and design and of course use of large panels (mostly).

Andy, yes, perhaps some "invasion stripes" would do the trick!

Ashley

[Paul TParticipant @pault84577]

Question……..

Are we supposed to grind flats on the motor shafts for the grub screws to drive on, or do we rely on the grub screw acting as a clamp?

Bob

The first port of call should be the motor / propshaft manufacturers but in the absence of any such information and instead of grinding some flats you could simply grind shallow groves lengthways on the shafts, providing you don't go to deep and cut an equally spaced set of groves ( like cutting a knurl) you shouldn't ruin the balance and you would give the grub screws something to grip.

Paul

[Trevor HollowayParticipant @trevorholloway99134]

One small flat (2mm x 2mm) the right distance along the shaft should be fine and will give enough flat for a grub screw. Its only a miniscule of metal removed but taken up by the grub screw sitting nearer the shaft centre line. I sincerely doubt any device could measure the difference in the out of balance vibration.

[Bob Abell 2Participant @bobabell2]

Thank you, chaps, for your comments regarding the motor shaft drive flats

That`s what I would have done myself really……Just making sure I wasn`t missing anything

Why don`t the motor makers do it for us?

Bob

[Bob Abell 2Participant @bobabell2]

Made a serious start on hull

Not much leeway at the stern for waterline ballasting?

Should be interesting on it`s first floatation test?

Looks like….Moby Dick?

Bob

[Paul TParticipant @pault84577]

I'm not worried Bob, but I am on some serious medication and often talk to the goblins who live in my shed.

[curlyParticipant @curly]

Hi Bob

I don't know if it helps, but I bought a job lot of brushless motors, ESC's, several of the motors had flats on them, They look like they where put on by the manufacturers. the Brutus looks a great boat, and a credit to your skill as a builder

Curly

[Bob Abell 2Participant @bobabell2]

Hello Curly

Many thanks for your kind comments….Much appreciated

Bob

[Bob Abell 2Participant @bobabell2]

Hello Paul

Let's have a talk about the sailing characteristics of Brutus?

I know it's too late now, and I'm not that concerned about failure and I realise, this should have been discussed before we started the build…..etc

The stern is only 12mm deep!……If that!

On your drawings, all the heavy stuff is at the back!…….Why?

The waterline looks to be on the joint line of the rear hatch?

Is this the spec the Goblins thought up?

I have complete faith in your design skills and await the results with great anticipation!

I am amazed that at such a late stage of the build, I have only just realised my trepidations and I am further amazed that none of the readers have cast dispersions either!

Luckily, if things go wrong, I have a cunning plan!

Fit the outrigger sponsons, I mentioned at the start of the build, as suggested by the Fairies that live in my workshop!

All good fun and it adds interest to a very exciting project!

Now then, readers!…….This is your chance to shine!………Is the future……Success or failure?

Doubting Thomas

[ashley needhamParticipant @ashleyneedham69188]

Bob. The landing craft i am building for our D-day event is 5 feet long and 1 foot wide, It is flat bottomed, I will be very suprised if it has a draught of more than 3/8".

Brutus is wide and flat at the rear, it has increasing levels of bouyancy forward (due to the in itial very thin footprint on the water `coz of the axe bow. Paul says he expects it to float levelish (cant remember the exact attitide) and i would fully expect that to be the case despite the size and apparently low rear end, based on my experience.

I cant see that you will need any ballast at all, but should leave scope to move the batteries about to correct any list, or to obtain a better attitude when at speed.

As to how it will go…not sure.. it may be fast but keep a substantial portion of the bow in the water, unusual for a speedboat, but this is an unusual front. Turning performance..who knows? but the centre ridge and shaft skegs should help.

Ashley

[Bob Abell 2Participant @bobabell2]

Thank you, Ashley, for your kind words of encouragement

I think I'll use some of that waterproof tape to seal the first few inches of the hatch joint, to be on the safe side?

I wonder what Paul will say, when he reads my tale of woe?

Bob

[Bob Abell 2Participant @bobabell2]

Looking at the model again, I may have over reacted chaps

When the rear section of the hatch is glued and sealed, We've got more hull depth before the water gushes into the rudder chamber…..Probably about a whopping 40mm!

Sorry Paul….Panic over

Bob

[Bob Abell 2Participant @bobabell2]

Latest WIP pictures

Hull dark grey painted……..Needs a separating line, as the Sellotape line is not very crisp

Bob

[Paul TParticipant @pault84577]

Doubting Thomas

You are having the same thoughts and worries that I had back in October but Brutus should float fairly high in the water and as the speed increases the model should rotate around the mass of the motors, hence having the equipment where it is. The addition of the cooling fans has changed the characteristics slightly so there will be the need to trim by moving the batteries once the model gets on the water.

The colours look very good and I don't think that you need a dividing line between the upper and lower hull but if you do decide to use one I would suggest a very thin black pinstripe.

Paul

[ashley needhamParticipant @ashleyneedham69188]

I think..NO pinstripe. Get a good crisp line there Bob. Decent masking tape, rubbed well down on the edges.

Pity, but a sprayed finish, black on the top fading to grey on the bottom would be spectacular, in an understated way.

Ashley

[Bob Abell 2Participant @bobabell2]

Thank you Ashley

Haven`t got time to rub down and repaint…….The Ellesmere show is only one week away!

Latest stage of play…..

Need to make a means of transport……

Going to assemble the rudder mech through the hatch, to see if it can be done

No access for a screw driver, you see

Shop floor to Drawing Office

We didn`t bargain for this!……..The Windscreen is in conflict with the foredeck!

We can either….Sand it away or build the windscreen up on either side?

Need your expert advice, please

Bob

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