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[Celestialsphere]

Hi everyone.

Here's my first boat design.

I have designed a modern work barge based loosely on the Eurocarrier type of vessel that is popular these days for all sorts of in-shore duties that require a stable work platform.



I am building this in 1/32nd scale as this will fit my work bench. It will be just over 800mm (31") long, 255mm (10") wide and the design(!)draft will be about 55mm (2.1") at about 6 kg displacement. The cross section of the hull is rectangular with a flat bottom. The freeboard will be about 43mm (1.7") on the mid hull.

The proposal is to use a 4 blade 45mm propeller in a MMB Kort nozzle. My model boat shop suggested a geared motor as the hull will be pushing aside a fair amount of water. Is a 12v lead acid gel battery through a 20amp ESC appropriate for this?

Any comments are welcome.

Cheers

Andrew




 

[ellisgarth]

HI ANDREW LIKE YOUR WORKBOAT DO U HAVE ANY DECK DRAWINGS.

[Roadrunner]

Hey Andrew,

 I would be interested to see how this one turns out are you planning on a build log on the forum? I'm sure others will agree that you posting your build is a worth while exercise!

[Norseman]

Hi Andrew

I'm having a problem seeing your images - no idea why. That's really a pity because I'm interested in crane barges / floating cranes. Here are two from the Mersey - long gone.  I'll check back later anyway.

Regards Norseman

[Celestialsphere]

Hi everyone,

Work has been progressing slowly but surely. I am now 80% through construction of the hull.

I think starting with a flat panelled craft was probably a good idea as once a piece is glued on all that's required is tidying up the edges and then sealing the wood to waterproof it. No fibreglass etc.

I will use the traditional model aircraft dope sealing technique. 






I took the advice of my model boat shop and purchased a Mtroniks Viper Marine 40 for my boat.

Cheers

Andrew

Melbourne, Australia.

[Norseman]

Hi Andrew

It's looking good - keep posting the build pics.

Norseman

[Celestialsphere]

Hi everyone,

More progress.

The hull is complete. It has two coats of sanding sealer applied. The stuffing tube is epoxied in. Last night I filled in the bow section with chunks of expanded polystyrene and then glued on the forward deck section from the bow to the first bulkhead. I put a slight camber in - about 1.5mm over the 255mm width. Hopefully enough to stop any water pooling on the deck. No pics of that yet as the clamps are still on.




Cheers

Andrew

Melbourne, Australia

[Norseman]

Hi Andrew

I figure the clamps must be off by now mate - so how about some pics? It looks good and solid so far.

Regards Norseman

[Celestialsphere]

Hi everyone.

Last night I took the plunge and lowered her into the 'Domestic Test Tank'. And she floats ! Ballast consisted of the 12V battery, a concrete paver brick and a couple of handfuls of lead sinkers. I reckon that lot would be around the 6kg that I had previously calculated would be required to take her down to her marks. Stability was very good. When the edge of the deck was pressed down to just above the waterline and released she returned very smartly to a level deck - no excessive rocking and rolling !

Now - onto hatches and electrical things.

Also I have attached a revised drawing of the proposed finished product. It will be 1/24 scale.

Cheers

Andrew

Melbourne, Australia

 

[Norseman]

Hi Andrew

You say it's now 1/24th scale - so have you changed any of the planned dimensions? Sorry if it's a daft question - I only really understand scale when it relates to an actual object. It must be quite difficult with something you build as a concept (well it would be for me anyway). Though looking out the window here I might just start a 1:1 Ark tomorrow. Winter in the UK has begun and it is spelt R A I N  .

Regards Norseman

[dave301bounty]

Are you any where near Airport west ,,ESSONDON ,mate of mine there into boats serious .

[Celestialsphere]

Norseman

To explain, the model hull is about 762mm long.

Therefore

At 1/32 scale the real boat would be 24400mm (24.4m) long. (that’s 762mm x 32)

At 1/24 scale the real boat would be 18288mm (18.28m) long. (that’s 762mm x 24)

So instead of a 24.4m boat as originally planned it will now be a model of a shorter, narrower, shallower draught boat (18.2m) using larger figures to represent 1/24 scale.

I hope that explains it... 





Cheers

Andrew

Melbourne, Australia

[Norseman]

Cheers Andrew

that's crystal clear now. Back in 1970 our maths teacher just threw things at us if we didn't keep up - or he caned us. Best ever was when he caned the entire class (six on the left hand) for poor homework. He even caned the swots at 100%. Good old Mr Larkin - so greatly missed by all at class 5x . 'C'mon boy 36 boys x 6 strokes each equals what'? erm is it 179 sir?

Anyway I'll keep watching your build log.

Regards Norseman

[Celestialsphere]

Hi everyone,

More progress.

It would have been late november when I temporarily installed a rudder and servo and got the boat into the water for a five minute spin around the lake. The plywood exterior has a couple of coats of sanding sealer on it so a few minutes in the water didn't do any harm the the wood. Of course I forgot to check the servo travel direction so the boat steered in the opposite direction to the stick but I worked it out in the end. I have built a neat looking switch/ fuse board that I will post on the forum soon. The motor runs through two universal joints. Steering in reverse was less the inspiring so I am building up the rudder to double the surface area. The kort nozzle may improve water flow over the rudder but I'm no expert. I have though about flanking rudders - any pro and cons ?

I have been working on the wheelhouse of my boat recently. I designed it on a CAD system and unfolded the resulting shaped to get all the shapes of the sloping panels. Just old fashioned geometry really. A full size print and a pair of scissors and some tape resulted in a paper mockup that gave a good sense of scale and a check of the shapes involved before I started cutting plastic.



I'm using 2mm stryene sheet assmbled with CA adhesive. The photo shows the structure half complete with a couple of temporary wooden braces to keep the whole she-bang square and align the sloping panels. Next I have to work out what glazing material to use - any ideas ?





Cheers

Andrew,

Melbourne Australia.

 

[Norseman]

Hi Andrew

Nice to see you back - I wish I could use cad, wouldn't even know what package to try.
That looks really neat and I'll keep watching for more.

To make you smile - it is beeping freezing cold in Liverpool and I'm working out in Wales tonight.
I suppose you are nice and warm down in Oz today.   

Regards Dave

[Celestialsphere]

Hi Everyone,

Some pix of the Kort support structure and bottom rudder bearing. The is made of a piece of plywood that is encased in styrene sheet. The bottom rudder bearing is  a cut down .22 Long Rifle cartridge casing that the 4mm shaft fit into nicely. Two small screws hold the whole piece in place so it's removeable for rudder maintenance.






Cheers

Andrew

Melbourne, Australia.

 

[Celestialsphere]

Hi everyone,

I have been working on the pushknees that these multicat boats have for pushing barges and to soften the blows from any other biffing and barging required in a workboats day on the water.

I have been using 2mm styrene sheet spaced to 12mm apart with plywood between. The 12mm gap will accomodate some rubber tubing I bought from a car shop. This should provide some protection on the model boat lake ! I bevelled the front edges with files and abrasive paper to form a crisp edge.

One of the knees has a series of holes drilled which I believe forms a ladder for divers or perhaps a way up out of the water if someone falls overboard. I really don't know for sure. I made a hollow section behind the holes to give it some depth. This is a free flooding space with a small hole drilled in the bottom to let the water out when the boat is out of the water.






Cheers

Andrew

Melbourne, Australia

[cuppa]

Nice work Andrew.

Cheers
          Jon

[Norseman]

Hi Andrew

I'm back as myself after the meltdown
Keep up the good work - I like it.

Dave

[Celestialsphere]

Hello Everyone !

After an extended hiatus from posting on the forum here is an update of my progress on the 1/24 scale Multicat workboat I am building.





The wheelhouse which is made of 2mm sheet styrene. The windows were drilled and filed and will be glazed with either picture frame glass or possibly thin glass from some old 35mm slide cases. The roof is removable and the angled edged will be painted with fluoro orange just like the real thing. I have bought some nice brass turned lights with coloured plastic glasses for the port and starboard navigation lights. These will be mounted on the side of the angled sections.



The push knees are rubber tube bought from an automotive shop. This was glued in with rubber toughened superglue (Cyanoacrylate). I have started using this better glue in place on normal superglue as it is more resilient and less brittle than the normal stuff although it is a bit more expensive and takes a little longer to grab.

The bulwarks are 2mm styrene. The tops are from 1mm black styrene sheet so if the paint rubs off the edge white plastic won’t show through. I will add some half round strips wear the mooring lines are likely to rub.
The interior showing the switchboard, lead acid battery and compartment in the front which will hold the bowthruster and RC receiver. I think a couple of clear acrylic covers might be an idea to prevent any splashes getting on delicate electronic equipment. The boat only has about 50mm of freeboard so note the aluminium gutter to catch any water that makes it through the flush hatch - I thought this was essential. As it turns out the model boat club lake here in Box Hill, Melbourne is very placid wave-wise so I rarely even get any water on deck at all. In heavier ‘seas’ I would expect some water to get in so there is the possibility of adding a pipe down to a bilge tank to keep the gutter clear, and even a bilge pump if necessary.



The removable bow ‘fence’. The real boat have this fence that can be craned out of slots on the push knees for operations over the front rounddown such as anchor handling, buoy recovery etc. This model version is made of 3mm ply covered with filler, sanded smooth then scribed to represent the planks of wood. Then some styrene strapping was added and a couple of lifting eyes from copper wire.


She's been on the water a few times now. Handling is good although there's no steerage at all going astern. A bow thruster is in progress to give a bit of control in that direction !

Cheers

Andrew

[Norseman]

Hi Andrew

Looks good; did you take any video? So what's next?

Regards Dave

[Celestialsphere]

Dave, I have a list of things to do. I will probably finish the wheel house and build a mast before painting all the bits that I have aready done, especially the styrene parts to protect them from sunlight. Then I will rough out the exhaust stack (funnel) and finish the bulwarks.
 
Here's some pictures of her - currently know a 'Hull No. 2' (no name yet ), on the lake pushing some model boat club barges. The pictures are from my old mobile phone so excuse the quality. Before anyone says anything I know the logs on the barge are not lashed down. This will be fixed.
 

 

 

 
Cheers
 
Andrew

[Howard]

Andew,
Just in case you missed it Did you see the personal message I sent you please.
                 Regards Howard.