Thames Sailing barge

[Bob Abell 2Participant @bobabell2]

Paul

The thought of the big barge lingers on and there are things and ideas to talk about

Kimmo says he uses only 2.4lb for the keel weight!

If we double the model size, I think we cube the keel weight?……33lbs….Not quite right, I know

Our main danger is getting blown over…….We could have slack sheets as the norm and pull in as required?

Just thinking out loud

The plank hull could have a deep lip all round, so we would have suction to help us

We could have a further thin plank at base depth which would act as a large damper and provide time for the Skipper to react to unexpected side forces

This sounds like good fun to me

Any comments. old chap?

Bob

[Paul TParticipant @pault84577]

Bob
If you give your plank a pointy end and a deep lip all the way around ……it would work.
Paul

[Bob Abell 2Participant @bobabell2]

Shop floor to Paul in the CAD Shop………..D- Day secret message….. "Violins are playing our song"

I`ve now got the plans and all the bumf for the Thames Sailing Barge……. "James Piper"……..Many thanks to Terry Miles of the Etherow Club for the loan of same

Our model will be loosely based on this prototype, but with a few lapses in accuracy where it suits us to exercise our Artists Licence

Bear in mind we are only still talking about the project, to get a feel for the job

The model has an 85" hull x 19.5" wide x 7" deep at midships

The model is extremely monstrous and absurd, but will be great fun to build and very interesting to view on the website

It will be full of unusual features, strange construction and ground breaking ideas!…..etc

The model in it`s early stages will be inexpensive to build and it will be no problem to abort at any point and scrapped.

The hull will be made watertight very early on in the construction stage to allow for early testing on the water, the feasibility of the idea. Testing for stability and heeling characteristics, we may need a powerful tugboat to tow the hull around the pond, which will be great fun!……… I know someone making one, that will do nicely

Paul, can you lash up a typical cross section. please?

The cross section is 19.5 across the deck and 18" at the bottom. At midships, the depth is only 7" deep

The camber is 0.75" high

Don`t think we`ll have a hollow plank now, as the hull is so shallow, but use local watertight boxes for the gear, but the hull will still be totally flooded!….ie…..No ballast required

The frames may be best made from constructed timber?….Rather than bandsawed plywood formers

We may need several weighted keels……Good idea?

Aye? Aye?………Casting off now, for me grog!…….Capt Bob

[Paul TParticipant @pault84577]

Captain Bob

Now that you have finished your grog can you get a copy of the James Piper information over to the drawing office so that we can start on the drawings.

Paul

[Bob Abell 2Participant @bobabell2]

Hello Paul, my long standing friend…..You won't take no for an answer!…..Good on yer!

As discussed via our PM's, I'd decided to abandon the build……..Due to lack of thread interest, which was most disappointing, I might add…..I will relent slightly and work with you on the design and see how it goes?

But have a problem as mentioned earlier, the Scanner won't work with my 64 bit PC!

We can't scan the drawings anyway, as that will infringe the copywrite!

We will design our own version, based on James Piper…..It's quite straight forward really

The cross section will explain most of the design

You've got the overall dimensions, as above……Make the side walls and bottom from what ever you recco?….10mm?

Make the top piece of the frame from…. 50mm stock with 20 mm camber…about 20 mm thick

The sides and bottom pieces from 40mm x 20mm and we'll use half lap joints

Just draft that out and submit it to the Co- designer for approval

Capt Bob…..Co-designer

[Paul TParticipant @pault84577]

Ok Captain

I will draw it up but I have to say that with these timber sizes the barge, if ever built, would need a trailer for transport and a crane to launch it.

Paul

[Bob Abell 2Participant @bobabell2]

Hello Paul

Feel free to change anything

I prefer the hull to be built in one length

If built, it will fit my campervan easily on it`s side

Bob

[Bob Abell 2Participant @bobabell2]

Captain Paul and First Mate Bob have made a tentative start on laying out our pipe dream…….But it may not be!

We have nearly decided on a project name…….Thomas Bell…..Not bad?

Scale 1" = 1 foot…..Chunky!

Simple hull, 85" long x 20" wide………..Built in several pieces……..Fully flooded

Thinking about flooded keel weights at the moment……Will it work?

Readers are very welcome to suggest constructive improvements

We are enjoying our design challenge at the moment

Bob

[lnvisiblemanParticipant @lnvisibleman]

Hi Bob

I've been giving this one a good peruse and find it fascinating as Popeye would say. You idea of using bowthrusters to counteract the lean got me to thinking about the problem of reaction speed. I think I have come up with a (probably stupid ) idea to move a counter balance as fast as the wind can change. Would it be possible to rig a pulley arrangement that would be attached to the mainsail boom causing a weight to slide across the hull as the wind pressure increases?

I await your derisive remarks with baited breasts. !

[Bob Abell 2Participant @bobabell2]

Thanks for your suggestion,,,,,Still can't remember your name!

We know what you mean, but we don't want any strange junk on board

We have a few more ideas to counteract the lean, but haven't decided which method to go for

Many thanks for reading the thread, feel free to suggest anything you bring to mind

Keep watching

Bob

[Kimosubby ShipyardsParticipant @kimosubbyshipyards]

Hi Invisible and Bob,

I think you are talking swing keels here, that's been tried and tested and done on some yacht designs. The idea was to keep the keel vertical despite lean caused by wind – from memory the idea was soon given up, too much weight below water doing it's own thing!

Thames barges were very "stiff" without much lean anyway, especially when loaded. It over pressed, they just collapsed the topsail, and then loosened the main if more "off wind" required. There was only ever two men on these boats, so KISS was the byword.

Kim

PS I'll have my barge out of its box at the weekend, so I'll measure my sail area for you. Are you going "coastal" or the full monty with a bow sprit?

[Bob Abell 2Participant @bobabell2]

Thank you, Kimmo

We haven't decided how the keel will finish up……I'm suggesting a flooded keel weight, just avoid humping lead about. It probably won't work, but shall try the idea out shortly. We are thinking of several keel weights

Paul is designing the cross section and hope to see it tomorrow

One nice idea is to control the barge using two trannies, as a bit of fun, keeping the craft upright will be a full time job

We may have to reduce sail accordingly, we have an idea of fitting two props, mid ships, pointing downwards, to counteract the heeling effect

Your comments are very welcome

Bob

[Paul TParticipant @pault84577]

Bob

Based upon your specification these are the first basic cross sections showing the water tight motor compartment and the free flooding areas

All timber components made from 4mm ply.

Paul

[Kimosubby ShipyardsParticipant @kimosubbyshipyards]

Hi Bob,

(I've got your draughtsman on a job for me!) My barge, albeit quite a chunky beast and nowhere near my new lightweight Lady Daphne, is at 1/24. My keel weight is about alb maximum, I use a smaller one in light airs.

When first built I had no keel/fin, just flat bottom and two large 12Ah 6V lead acids as hull ballast. The only time she capsized was when it was blowing a gusty 6/7 down our lake. Running before the wind was exciting, it was only when she got pooped and I tried to turn upwind (having forgotten to let go all sails) that she was knocked down (and stayed down because the batteries were not secured and had fallen onto the underside of the deck – the mast head stuck in the lake bottom and I got wet wading to the rescue.)

I have never had a repeat experience, mostly because I don't sail in strong winds (above 15knots) but even then I use much lighter ballast. My keel is 10" below the bottom, and is about 5" wide.

I estimate about 20-25lb for a 1/12 scale. Note, we only r/c the main sail and the sprit gangs. The foresail sets nicely when sheeted by "chain" to the fore horse. You will require to extend the rudder to get water grip.

I'll pop some pictures up soonest.

Two transmitters eh, our Commodore once played with two boats on one transmitter [27MHz], LH stick red boat, RH stick green boat – all went well till they took off in different directions, and in the middle of a grand regatta too!

Kim

[Bob Abell 2Participant @bobabell2]

Hello Paul

We may need some floatation compartments to support the batteries and gear somewhere along the length

Your sections look odd without a keel and keel ballast box and stringer strength?

Don't think we need any ballast in the keel, just a box shape that can take in water, the keel boxes could be fitted with horizontal plates to oppose the rolling effect

I realise it's your first layout, but are there any longitudinal stringers anywhere?

A side elevation will show the construction in a better light

Kimmo reckons the ballast to be about 25 lb, we could load two 12 lb lumps in from the top if need be

I'm only thinking out loud again at the moment…..Excuse the fragmented comments

Bob

[Amy jane SeptemberParticipant @amyjaneseptember49770]

I can stay silent no longer!

I need to know: Why has the invisible man baited his breasts? For what purpose? what is he hoping to catch

[Bob Abell 2Participant @bobabell2]

Thank you, AmyJ….We don't mind the occasional joke…….I think, he means ….baited breath……But we still don't know what he's on about!

Paul

We can't have water filled keel ballast boxes, after all……They have got to be heavier than water

Need about 3" of hull above the waterline, which means we need the hollow plank idea restoring?

Are you still splitting the hull?

We could make each half self sufficient and simply join them together after launching?

Worth thinking about?………A bit radical, but we've got two radio's anyway

More food for thought

Bob

[Bob Abell 2Participant @bobabell2]

Paul

It we split the hull halfway as already mentioned, we could make the keel and ballast act a s a location key, to hold both halves together, and could have a handle and loaded from above and into a hatch

Drawing to follow

Bob

[Paul TParticipant @pault84577]

Bob

Here is a simple layout plan showing the proposed positions of hull joints and major equipment

Paul

[Bob Abell 2Participant @bobabell2]

Hello Paul

I see you`ve used the co-ordinates sketch. The hull is quite an easy build, once we get the cross section sorted out

How will we make the joint?……..Location keys and wing nuts?

Might be a good idea to show the hatches and main mast at this stage

Are we still going for a two man crew?……Rudder and motor with Sail control separate?……Great fun to be had there!

How about showing a 5`-10" human lying alongside, to get an idea of scale?…..Or shall I do that?….Hee! Hee!….That should raise a few eye brows!

Bob

[Bob WilsonParticipant @bobwilson59101]

Did they have centre drop-down keels though? All the ones I saw had leeboards on either side that could be lowered and raised quite quickly. It is something I don't really know about, so I am not putting it forward as fact!

Bob

[Bob Abell 2Participant @bobabell2]

Hello Bob

They only had Lee Boards and a flat bottom, but we are having a weighted keel at the moment, for stability

I read they didn`t lean much either, can`t really believe that when unladen though?

When heeling over, they pivoted about the outside edge, that`s probably why?

No doubt, Kimmo will be on shortly……..He knows the ropes!

Bob

[Paul TParticipant @pault84577]

Bob

This shows the flooding areas in relation to the rest of the hull.

The joints will be location lugs and captured bolts / wing nuts.

Main mast is located in the battery compartment, removable hatches go over the equipment spaces.

I'm working on having a single control set simply because two people cant react fast enough to each others commands.

You can add a scale human if you wish to raise eyebrows.

Paul

[Bob Abell 2Participant @bobabell2]

OOOOoooooo!……That`s looking impressive?

How much water we`ll need, is a bit debateable, but we can simulate the sails and rigging weight quite easily, during the early motor tests……If we get that far!

I`ve used two person control before with my Colin Archer and it was great fun!

Here`s a comparison between Barbies boy friend at 5`-10" and our barge, Thomas Bell at 7`-1"

Who`s going to break it to the wife?………I`ll just say it`s one inch longer than Great Eastern…….And duck!

Bob

[Kimosubby ShipyardsParticipant @kimosubbyshipyards]

Hi Paul and Bob,

just looked at the proposed plans and have the following comments.

The keel, and associated ballast, is positioned under the mast tabernacle, the leading edge aligned almost with the aft edge of the mast box, about 2 inches back/behind the mast. That, on your plans Paul, puts it where you have indicated the 12V battery box. The battery box goes aft of the keel box, and some "ballast" needs putting in front of the mast to trim ship. Putting the keel anywhere else and the boat just will not sail. Just aft the mast and she will be slightly windward and responsive.

Look here, my barge on her side with her big fin

Here, ready to assemble at he water's edge with the small fin [2lb]

and here assembled ready to go – takes about 4 minutes to rig and locate the keel.  ALSO note the rudder extension, red/yellow stripes, to enable steerage when sailing (water grip)!

 

You've also shown a central motor, which for a new design is ok, but in real life 96% of shafts exited on the port side of the keel this being due to no skipper or barge owner wanting to attempt to drill the dead wood and stem post to try and site a central shaft. AND having a centre shaft exit means you'd have to fiddle the rudder shape, whereas a side exiting shaft leaves the rudder flush and square to the rudder post. A port side prop on a large barge hull is no problem, there were some 3000 barges fitted with engines just so. The rudder configuration has to be maintained for the barge to keep sailing qualities.

If you look hard at the first image, at the stern you can make out the 4 blade prop in the rise of the aft port quarter.

Hope this helps, Kim

 

Edited By Kimosubby Shipyards on 09/05/2014 20:25:58

Edited By Kimosubby Shipyards on 09/05/2014 20:27:20

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