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Author Topic: Natterer - A shipbuilding Odyssey?  (Read 24979 times)

Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #50 on: November 08, 2011, 09:49:55 am »

Time, I think, for another section for your delectation.



‘Natterer’ – A shipbuilding Odyssey? – Part 9


Right; At the end of the last instalment I think I’d just about got to the stage where I had a functioning engine, and a functioning boiler – that’s good, all I have to do is put them together and we’ve a powerplant!  Well, no actually – we’ve got an engine and a boiler: full stop.

The next fun bit is to put it all together, and suddenly you realise the combined weight of engine, boiler, hull and ancillaries is rather considerable, (around 80lbs weight – alright 36 Kgs) and the workshop is in an attic room.  Ann didn’t seem particularly overjoyed at the thought of the boat residing in the dining room (spoilsport) and I didn’t fancy moving 80 lbs up and down two flights of stairs.  A cunning plan was called for!  Why not make the entire powerplant removable?  The powerplant and the hull each weighed around 40 lbs, so readily transportable, and there were plus points in that it made the powerplant so much easier to work on outside the hull.

A baseplate was built using a brass sheet sitting on two brass angles, to which were attached the engine and boiler. The baseplate was secured in the hull by horizontal tapered pins engaging in holes in a brass plate secured to one of the frames at the front end, and sitting over two studs at the rear.   Thus the entire plant could be lifted in and secured by two nuts, with a sliding dog-clutch joint to connect to the prop-shaft.  Of course, this meant in turn that all the controls for the engine/boiler had also to be mounted on the baseplate, but we’ll come to that particular headache later.

The baseplate gave me loads of room to mount all the other ancillaries, and the feed pumps (hand and engine driven) were mounted, together with oil condenser/trap, by-pass valve and all the associated plumbing.
I also elected to carry a twenty/twenty-five minute reserve of feedwater in the boat, carried in two inter-connected saddle tanks either side of the boiler.  These were folded up from copper sheet using a metal folder in the maintenance section at work, and soft-soldered.  They’re an awkward shape to construct, but look well in the boat, painted a sort of red-lead colour. Connection from the tanks to the feed pumps is by means of a quick release coupling, as used by the steam loco lads between tender and engine.
All the plumbing was by now causing my head to hurt, so I carefully drew out a plumbing diagram using Excel on the computer.  I’ll be able to refer to it in years to come when my brain becomes even more addled than it is currently! (more like weeks at the present rate)
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #51 on: November 11, 2011, 05:18:47 pm »

We're starting to get into the nitty-gritty of making the thing work, so read on.
I'm always looking for better ways to do things, and as this was my first steam boat I'm sure there is plenty of room to improve, so please - let me and other modellers know!


‘Natterer’ – A shipbuilding Odyssey? – Part 10

As previously alluded to, the firing for the boiler was to be by gas, and a lot of heat was going to be required.  The burners were to be a couple of 5/8” turbo burners, firing into a sealed firing tube in the bottom of the boiler.  (Remember Smaug?) (Hands up anyone who doesn’t know who Smaug was) These proved tricky to regulate reliably, to the point where they would readily extinguish at low gas flows, so a much smaller burner was mounted piggy-back style on top of the main burners, set to run continuously as a pilot light. 

As I had decided the power-plant was to be removable, the burner assembly has to move back when the plant is installed or removed, so it slides backwards and forwards on two steel bars, and can be locked in position

The main burners were then controlled by a servo-driven valve controlled by a Cheddar ABC automatic boiler control set-up.  For anyone not familiar with the ABC unit, it is basically an electronic box of tricks that continuously monitors the boiler pressure in the boiler (through a temperature sensor) and increases the gas flow if the pressure drops, and decreases it if the pressure rises.  It also monitors the water level in the boiler sight glass and regulates the water flow in to the boiler from the boiler pump by means of a servo-driven by-pass valve. ( Natterer has two sight glasses, one fully working for display in the front cockpit, and a further one hidden from view in the engine room, mounting the water level detector)  As an added bonus, it also monitors the water remaining in the water feed tanks, and shuts down the whole system if the reserve goes too low.

The gas supply comes from a pair of gas canisters mounted in the bows, feeding to a common feed pipe.  I decided on two canisters to try and overcome the freezing effect inherent in evaporating gas from a container, and have so far had no problems.  If necessary, I could invert the canisters, and feed liquid gas to an evaporator warmed by the burners, but that’s for the future.

Of course, as this was my first steam driven model, I had galloping paranoia over the prospect of the system shutting down unexpectedly, which  could be a bit of a problem if it occurred in the middle of a lake or river, so as I had some  room under the rear passenger well of the launch,  I decided to put in an emergency drive system in the form of a geared electric motor, driving through an electro-magnetic clutch, and geared to the prop-shaft.  In the event of an emergency, I only have to flick a switch on the transmitter, and control of the boat transfers from the steam valve to an electronic speed controller, the clutch engages, and I can bring her in.  The power comes from a small lead-acid gel battery, which gives sufficient power for 5-10 minutes sailing.

The steam engine remains connected to the propshaft when the emergency electrics are employed.  I had some doubts at development stage as to whether this was practical, as I was concerned that I could be trying to turn a ‘steam-locked’ engine as well as the propshaft, but the system has worked well on test (never had to use it in anger!)  The resistance from the steam engine is high, and the electric (geared) motor pulls a lot of amps, which accounts for the short duration of the stand-by battery – but then I only need a minute or so to bring her in.

The electronic clutch was obtained from a friend who worked in the electronics control industry, and is only about 1.5” in diameter.  I’ve looked for a ‘spare’ just in case, but never found one – the majority appear to be in the 3” upwards range. I’m told the older photocopiers may be a useful source!

As with the plumbing, concerns over future memory capacity ensured I produced a full circuit diagram for the whole set-up! – one for the motor wiring, and one for the R/C changeover. I’m afraid my grasp of electronics is fairly basic, and I tend to rely on simple things like relays, rather than anything more sophisticated. 

Although out of sequence in this tale, it was found that when the launch was sailed, the emergency system worked so well that an experiment was made with a battery pack of four 12v lead-acid gel batteries replacing the steam plant (same weight!)  The boat sailed perfectly all day, and provides a perfectly acceptable alternative drive should I not want to use the steam plant.
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #52 on: November 16, 2011, 05:29:22 pm »

Part 11 for your perusal!

I'm beginning to feel like Mick (Patternmaker) did at the start of the month - is there anyone out there?  No responses, questions, brickbats - should I carry on posting?


‘Natterer’ – A shipbuilding Odyssey? – Part 11


You will remember that I had decided to assemble the engine and boiler onto a baseplate, so I could remove the power-plant in one go.  I had spent a lot of time and thought on exactly how I was going to control the engine and boiler, and in the end determined that the servos to control the reversing lever, boiler feed by-pass valve and whistle would all sit on the baseplate and come out with the power-plant.  By dint of careful planning of pipework and placement of valves it was possible to get all the servos together in one block, which could then be hidden by the ubiquitous ‘wooden box’, with short connecting links coming out of the box to connect with the appropriate valves and levers.

The boiler also had to carry the boiler pressure temperature sensor, and the water level sensor, so in all that made five sets of leads coming off the power-plant.  They all converged into the ubiquitous box, and were connected into the back of a “D” type 15 pin plug.

The steam throttle valve was a standard globe valve on the steam line from boiler to engine, and was so arranged that it engaged via a simple dog clutch onto the output from a sail winch servo, fastened into the structure of the hull.  The sail winch then had a sufficient number of turns to fully open the globe valve. 

So we now had a power-plant that would slide down into the hull, engage with the tapered pins previously mentioned, and then sit on the two studs, picking up the steam valve servo en route via the dog clutch.  All I had to do was then plug in the electronics via the 15 pin plug, connect the drive to the propshaft and connect the water tanks via a quick-release coupling.  Takes about a minute! (or two, and a lot of swearing if my thumb gets in the way)

Reference to the photos should hopefully make the arrangement clear! (Or not, depending on the level of my erudition)  The steam valve was arranged to end up in its own ‘locker’ on the hull, and be hidden by a removable lid.  The second globe valve you can see in the same steam line is permanently fully open and is cosmetic, being visible through the engine room casing.

By now there were 6 servos, 3 sensors, 2 relays, a speed controller, an electro-magnetic clutch, an electric motor, a boiler control module, a receiver and various batteries floating around within the confines of the hull, all hoping to eventually meet up for fun and friendship, possibly leading to more.  All the leads had to go somewhere, and this was under the decking at the stern.

A mounting plate (green in the photos) was made up, holding the radio receiver, ABC Boiler Control System, their associated battery packs, and various on/off switches and charging sockets.  I started with a Fleet radio system, purchased many years ago when I thought I was somewhere near finishing(!!!)  However, since 2.4 has arrived on the scene, I’ve changed to that, mainly to avoid frequency clashes.  I’ve used the Fleet outfit in other boats, as well as Natterer, and it is still going strong, having never let me down.

I fitted wooden channels with covers through each side of the rear cockpit to carry all the wires, running under the slatted seats, so the wiring is hidden. (Visible in the shot of the electric motor)
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BarryM

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Re: Natterer - A shipbuilding Odyssey?
« Reply #53 on: November 16, 2011, 07:10:23 pm »

Ted,
Keep going; this thread of yours is informative and entertaining and it's helping me by giving ideas for my project.

A certain 'B Y' (as in 'Bring Yer Own Young', who may be known to you) is also assisting me but he regards steam as a dangerous innovation in shipping and the switch from oil to electric light as the work of the devil.

Regards,

Barry M
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derekwarner

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Re: Natterer - A shipbuilding Odyssey?
« Reply #54 on: November 16, 2011, 07:24:40 pm »

Many are interested Ted  %) ....the first steam valve driven by the sail winch...

Is it a globe valve or a needle valve?
Does the seating torque of the sail winch create any issues when unseating that same induced closing/seating torque?...... %% Derek
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Derek Warner

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Illawarra Live Steamers Co-op
Australia
www.ils.org.au

thelegos

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Re: Natterer - A shipbuilding Odyssey?
« Reply #55 on: November 16, 2011, 08:29:05 pm »

Hello Ted, we are watching although my time has been limited by excessive searching on the internet about model steam engines, boilers and assorted launches - yes that little niggle is on my shoulder telling me I need to do this!!

The biggest problem is where to start, particularly the engine and boiler. I was taken with an oscillating V-twin seen in action a few weeks ago which could be reversed; then a Stuart Turner V10 which was forward only and thoughts turned again to the Kitchen rudder. As an aside I've got hold of a 1983 Model Boats magazine with a very good article about building the rudder, including a development of the rudder sections with dimensions and information about how to adapt a Tx for single stick operation. If you would like it copied PM me.
Used equipment is so variable and quite expensive so a poorly judged purchase can be costly mistake so the research will continue for now.

So please keep it up, this is a complicated and very different side to model boating for me and this kind of information is fantastic. I wouldn't even be considering it if it were not for the features from yourself and Mike.

Many thanks,
Roger
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Patternmaker

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Re: Natterer - A shipbuilding Odyssey?
« Reply #56 on: November 17, 2011, 03:04:48 pm »

Part 11 for your perusal!

I'm beginning to feel like Mick (Patternmaker) did at the start of the month - is there anyone out there?  No responses, questions, brickbats - should I carry on posting

I know the feeling Ted, it does make you wonder if is worth the effort, but if it has inspired someone it makes
it worthwhile, as I am nearing the end of my build I may well carry on.

Your Natterer is a far more complicated build than mine with all the electronics absolutely superb.

Regards Mick
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steamboatmodel

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Re: Natterer - A shipbuilding Odyssey?
« Reply #57 on: November 17, 2011, 11:23:25 pm »

Please carry on, I am following this very carefully as I have been asked to install a boiler and engine into a 50" x 13" model launch. I have decided to copy a number of your Natterer features in it.
Regards,
Gerald.
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #58 on: November 18, 2011, 10:54:47 am »

Thankyou, Barry, Derek, Roger, Mick, Gerald:
You have restored my faith!  Further ramblings will follow.

I've just realised that one of the photos in the last posting showing the steam valve sail winch was a very early one, taken while I was still developing the control systems, and shows a couple of servos to the right, apparently fastened to the main hull structure. Please ignore, as I later moved them to the lift-out baseplate!

Derek; the steam valve is a needle valve, or more correctly perhaps a cone valve, with the servo giving about 4.5 turns, compared to the valve's 5 or 6.  I've set it up so the valve doesn't close tight, so there is no stalling of the winch at either end of it's travel.  The tiny amount of steam passing the valve when shut is not enough to turn the engine, while there is plenty of steam on full throttle with the valve 90% open.

Mick; although my build is complete, I still get inspiration from your postings - particularly as I would like to consider a clinker hull on my next project.  Your workmanship is superb - please keep it coming!

Roger; yes, I would be very interested in your info. on the Kitchin rudder - will send you a PM.

Barry; I've known Bryan for some 25+ years, ever since we each built ourselves VERY large models in the shape of cars - the Gentry - modellerd on the MG TF (1953 version, not the later one) - he's a superb modeller and raconteur, very helpful and supportive.  (might even get a pint out of this)

Regards

Ted
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HS93 (RIP)

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Re: Natterer - A shipbuilding Odyssey?
« Reply #59 on: November 18, 2011, 11:03:48 am »

Ive read it right through twice, some great ideas, when you get posts like yours and Mick's it's hard to comment when everything is done so well.

peter
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ooyah/2

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Re: Natterer - A shipbuilding Odyssey?
« Reply #60 on: November 18, 2011, 12:04:39 pm »

Ted,
 Knowing that you have said that you reduced the bores in the launch engine to 3/4" bore which brings the engine more or less in line with the D10.and that the steam valve operated by a sail winch and 4.5 turns gives enough steam.
If the globe valve shown is a purchased valve the cone will be 30deg included, needle valves are usually used when very fine tuning is needed, i.e. on a displacement lubricator.

I like the idea of a sail winch but baulked at the cost so for the D10 in my steam tug CERVIA I made a valve with a 60deg included cone and screwed the valve stem 3/16" x 24 Whit which gave a quick lift using a standard servo with 90deg movement, this provides enough steam, any more and it would drive the boat under. ( pic enclosed ) it's all a bit of a squeeze.

Don't be down hearted at the lack of response, as I have said to Mick before you must not forget that the majority of steam modelers don't scratch build like you and Mick but purchase their steam plants and fittings so some times it's a bit beyond them, so your postings can be of great value although you don't get many questions it is a great encouragement for somebody to maybe one day have a go at making your own steam plant.
As Mick says if you inspire one person it's worth it.

Guys please don't get up in arms as I can assure you that I am not down crying you and all of the steam models posted are absolutely fabulous far above any model boat that I could produce whether scratch or kit built.

To those who don't know 30deg included angle gives a finished angle of 60 deg, like wise 60 deg gives 120 deg.



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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #61 on: November 19, 2011, 05:37:43 pm »

Hi ooyah/2 (sorry, don't know your christian name!),

I'm afraid I'm guilty of a bit of sloppy writing - You are quite right, I should have said cone valve, and not even mentioned needle valves!

I can't take any credit for the idea to use the sail winch and cone valve, as it was suggested to me many years ago by the gentleman who owned Bruce Engineering when I talked to him at Harrogate

Having said that, I like the idea of your quick-lift valve very much, and may well incorporate in the next boat, but don't hold your breath until I build it - 30+ years is a long time!

Regards

Ted
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ooyah/2

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Re: Natterer - A shipbuilding Odyssey?
« Reply #62 on: November 20, 2011, 10:16:04 am »

Hi Ted,
No you are not guilty of sloppy writing, you never mentioned needle valves it was Derek our antipodean friend who mentioned it.

In doing some back reading of your write up you mention not reversing a car at 70 mph without stopping to engage revers.
I think you should keep in mind some of our electric driven modelers who can at the flick of a switch revers their models and conveniently forget that a steam boat takes a bit of stopping.
I originally had a standard servo operating the Stevenson revers gear and a club member came across my bow so I had to whack the boat into revers only to find that the standard servo wasn't up to the pull.
I now have a 15kg steel geared servo so it's now not a problem in emergencies the boat flips into revers with no ill effect from full ahead to revers.
I am not advocating that this should be a standard proceedure but it's there if required, remember you have an 80lb boat under steam.


What have you done about getting your boiler certificated as the blue book on testing has some very stringent requirements on boiler design and earlier on when I asked who made the INGLS  boiler you said that no record was available, it sure looks well made by somebody who new what they were doing.
It's more or less a copy of a K.N.HARRIS  design  , see page 154 of his book MODEL BOILERS and BOILER MAKING.

It's a very impressive build, you and Mick have set some standard for us to achieve, well done both of you.

Sorry about not signing of on my last post.

George.
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #63 on: November 20, 2011, 06:00:14 pm »

Hi George,

Yes, Natterer takes some stopping! Having said that, the small steam launches on Windermere generally chugged around at perhaps only 4 to 5 knots, and oddly enough, Natterer looks best at relatively low speed - she looks altogether too hurried when flat out, albeit she sails very well at top speed.  I take your point about the reversing servo - mine is steel geared, but more because I had the servo rather than anything else.  The rudder servo is ahigh torque servo, as the rudder is very large, and I imagine the forces on the servo are high.

The boiler is indeed very similar to K.N.Harris' design, and I do imagine this had some influence on the design.  I mentioned when I acquired the boiler that I checked the design thoroughly (I was a civil engineer, and latterly worked in a consulting engineers design offices) Really it was a reverse design exercise, and involved reverse designing to confirm the boiler would be good for up to 120psi, with a factor of safety of 10  - q
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #64 on: November 20, 2011, 06:16:01 pm »

Oops! - mucked up the posting - full text as follows:


Hi George,

Yes, Natterer takes some stopping! Having said that, the small steam launches on Windermere generally chugged around at perhaps only 4 to 5 knots, and oddly enough, Natterer looks best at relatively low speed - she looks altogether too hurried when flat out, albeit she sails very well at top speed.  I take your point about the reversing servo - mine is steel geared, but more because I had the servo rather than anything else.  The rudder servo is ahigh torque servo, as the rudder is very large, and I imagine the forces on the servo are high.

The boiler is indeed very similar to K.N.Harris' design, and I do imagine this had some influence on the design.  I mentioned when I acquired the boiler that I checked the design thoroughly (I was a civil engineer, and latterly worked in a consulting engineers design offices) Really it was a reverse design exercise, and involved reverse designing to confirm the boiler would be good for up to 120psi (working), with a factor of safety of 10  - quite happy with that, and I imagine any boiler design engineer would be also.  I also had an inspector certificate the boiler for me, mainly to ensure there were no leaks.

Since completing the boat last year, a series of problems (not boat related!) have prevented me from re-certificating the boiler, so apart from extensive bench testing, I have restricted live steaming to test runs on very secluded water, with no members of the public around.  When in public, I've used the alternative electric drive - very successful! Hoping to get re-cetificated this winter.

Regards

Ted
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #65 on: November 20, 2011, 07:02:52 pm »

A bonus today! - Two parts together!
It's happened because I've realised I don't have any photos of the next stage (Part 12), which would make the post rather short.
I'm really sorry about the photo showing the making of the gunwhales in part 13 - it was the only one I had! (and yes, it is yours truly)


‘Natterer’ – A shipbuilding Odyssey? – Part 12

By this stage, I’d temporarlily had enough of the mechanicals, and decided it was time to work on the decks and topworks.  But since varnishing the hull, I’d been talking to a friend about the problems I was having with a vintage electric launch, constructed with similar sized planks to Natterer.  Every winter, after a season on the river, she would dry out and the planks would shrink.  The next season she would leak like a sieve until she took up again.  My friend is very much in to model yachting and suggested I should try one of their techniques by glassing the hull on the outside.  Apparently the model aircraft boys use this as well to cover the wings. Very wary about this, but decided to experiment on an old hull.  I used a very fine glassfibre cloth, almost like a thin sheet of satin, draped over the hull and stippled through with resin.  It becomes instantly see-through, and can be moved around to cover the contours of the hull.  When dried, it can be further resined to cover any “starved” areas, and then polished to a high gloss.  The finish is superb, with no seam lines, and in fact it is impossible to tell it is there other than on a sharp edge, which will end slightly rounded! 

Anyway, I next tried it on the vintage launch and it was fantastic!  No more shrinkage/leakage problems.  So after a couple of seasons with the launch, and no ill effects, I took the bull by the horns and turned Natterer upside down before slavering paint stripper on all my nice varnish.  (Yes – it took a lot of nerve!) When every last trace of varnish was off, I draped the cloth over her and started with the resin, working from the keel outwards.  It was quite amazing the way the cloth could be moulded to the hull, and I found that one piece of cloth covered the whole hull in one go, with the only ‘seam’ being on the stem (which of course is covered by the brass stem piece.  I seemed to be polishing for a week, but what a finish!  Obviously, you couldn’t use this technique on a lot of scale boats, as the finish would be too high, but the steam launches were ‘big boy’s toys’ and generally finished to a very high standard, so quite acceptable.

I’m afraid no pictures for this stage (I was as nervous as h***, and forgot to take any!

So lets go straight on to the next part


‘Natterer’ – A shipbuilding Odyssey? – Part 13

Anyway, on to the topworks.  Natterer is flush-decked fore and aft, and also in the mid-section, over the power-plant, with fore and aft cockpits for crew and passengers.

Nothing particularly of note about the basic deck framework and planking, as it was all straightforward framing, albeit of quite large size.  The planking on the mid-section was parallel, but that on the fore and aft decks was gently curved to follow the line of the gunwhales, before being joggled into a kingplank on the centreline, and so had to be cut out of extra-wide stock. Black card was used on the planking edges to represent the caulking.

The gunwhales themselves were a challenge, as they were 20 x 3mm in section and I wanted them in one piece from bow to stern.  This entailed persuading them to follow the line of the gunwhale, meaning they had to be curved in the plane of the minor axis (i.e. flat)  This meant steaming, and a steam chest was rigged up using a length of copper pipe, well lagged, and a domestic wallpaper steam stripper to produce the necessary steam.  The shape of the gunwhale was transferred to the building board, and a series of blocks screwed down each side, which would enable the timber to be clamped in position after steaming.  The gunwhale was to be bent on a rather tighter radius to allow for the inevitable relaxation that would occur when the clamps were loosened.

The gunwhales were steamed for about fifteen minutes, and then quickly transferred to the board, where myself and a friend clamped them up.  Absolute poetry in motion, as the pair of us danced and wove around each other wielding wedges and hammers – actually a lot of tripping up, hitting of thumbs and even a few naughty words. When dry, they were released, and relaxed as anticipated to take up the required shape, before they were firmly screwed to infill blocks between the gunwhale strake and the internal stringer.  Job done!

The remaining timber works on the deck included making access hatches in four locations, each with an inset brass lie-flat handle.  No commercial items available at this sort of scale (if indeed at any scale) so they were hacked and milled out of brass sheet, and yes, they do work!  There is a very pretty looking skylight over the engine so you can look at the whirly bits while they’re working (shades of looking at the engines on the Isle of Wight ferries when I was younger (much younger)

While making the handles for the hatches, I realised it was really quite difficult to envisage the size of fittings required, as with the odd scale of 1:4.5 the crew was going to be rather large – in fact the captain is 16” (400mm).  The solution was to produce “George”, an articulated two-dimensional figure, which could be sat in the boat as necessary and enabled me to sort out seat heights, wheel sizes, reversing levers, Windermere Kettles and so on. Very useful, and I’ll use similar mock-ups while building any future boats.
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ooyah/2

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Re: Natterer - A shipbuilding Odyssey?
« Reply #66 on: November 21, 2011, 09:25:00 pm »

Oops! - mucked up the posting - full text as follows:


Hi George,

Yes, Natterer takes some stopping! Having said that, the small steam launches on Windermere generally chugged around at perhaps only 4 to 5 knots, and oddly enough, Natterer looks best at relatively low speed - she looks altogether too hurried when flat out, albeit she sails very well at top speed.  I take your point about the reversing servo - mine is steel geared, but more because I had the servo rather than anything else.  The rudder servo is ahigh torque servo, as the rudder is very large, and I imagine the forces on the servo are high.

The boiler is indeed very similar to K.N.Harris' design, and I do imagine this had some influence on the design.  I mentioned when I acquired the boiler that I checked the design thoroughly (I was a civil engineer, and latterly worked in a consulting engineers design offices) Really it was a reverse design exercise, and involved reverse designing to confirm the boiler would be good for up to 120psi (working), with a factor of safety of 10  - quite happy with that, and I imagine any boiler design engineer would be also.  I also had an inspector certificate the boiler for me, mainly to ensure there were no leaks.

Since completing the boat last year, a series of problems (not boat related!) have prevented me from re-certificating the boiler, so apart from extensive bench testing, I have restricted live steaming to test runs on very secluded water, with no members of the public around.  When in public, I've used the alternative electric drive - very successful! Hoping to get re-cetificated this winter.

Regards

Ted


 Hi Ted ,
You have me confused, you say that you had a boiler inspector test your boiler and certificated it to 120 psi.
Now as it was a boiler with an unknown history with no certificate it would need to be tested as a new boiler which should be tested to twice the working pressure which at 60 psi. needs the 120 psi hydraulic test.

You previously said that the engine runs between 30 psi and 90 psi so if you have run the engine at 90 psi you must have screwed down the safety valve  which invalidates your test certificate as the inspector would have set your safety valve to lift at 60 psi and marked your pressure gauge accordingly

When you have another test done I would suggest that you get it hydraulic tested to 180 psi which will keep you insured at all pressures up to 90 psi.

The boiler looks as if it's a perfectly well engineered one and 180 psi shouldn't be of any trouble.

Please don't think that I am being a Job's worth but you may go to some club meeting and on inspection of your certificate which is for your boiler /engine working at 60 psi and when asking you to fire it up the pressure goes well above the 60 psi mark without the valve lifting you might be refused permission to sail under steam as your certificate will be deemed invalid.
George.
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #67 on: November 22, 2011, 10:39:16 am »

Hi George,

Sorry about the confusion - Most of the sections were written years ago, before I actually put the whole boat together. When I purchased the boiler, I thought I would be probably be running the engine at 60 to 90 psi. When I did the calcs, it indicated the boiler would be OK for better than 120psi working pressure, so no problems.  The boiler was then inspected and tested to 180 psi, in line with my assumed top end working pressure of 90 psi. The 120 psi working pressure mentioned in the text was the pressure I calculated the boiler could run at if required, but I never intended it to run at that pressure.
In practice the boat runs perfectly at pressures between 30 and 60 psi.
The original boiler test was carried out about ten years ago, and the regulations have changed a lot since then, as you are aware.  The boiler will have to be re-submitted as a new boiler, and tested accordingly, but until I get around to that, she never sails under steam with anyone around.  Thank heavens for the dual drive!

Ted
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ooyah/2

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Re: Natterer - A shipbuilding Odyssey?
« Reply #68 on: November 22, 2011, 08:30:50 pm »

Hi Ted.
I'm like Saul ( Paul ) after his Damascus road experience when the scales were lifted from his eyes and things became clear.

As you have already had the boiler certificated, all be it 10 years ago, if you still have the certificate it needn't be classed as a new boiler and pressure tested to twice the working pressure.
You can have it tested to 1.5 times the working pressure of the original test and if you only wish to run  at a max of 60 psi the boiler inspector can set the valve to lift at 60 psi and you still have the greater capacity up your sleeve if you ever wish to use it, but remember if you ever alter the safety valve setting you will require another test.

I totally agree with you in the max of 60 psi which is ample to drive your modified launch engine, at 90 psi you would be competing with my flash steamer and you would scare the living day lights out of your crew.

I read with interest your reluctance to strip the varnish from the hull but the success of coating it with glass cloth and resin will keep the hull good for years.
My steam tug CERVIA at 42" long is now about 45 years old and when building I sanded the outside and coated it with several coats of resin, wet and dried between coats and to date there is not even a sign of cracking or blemishes.


Don't be afraid to sail your launch with some public around, there is so much scare mongering about boilers exploding and people being injured.
I have been involved with steam boats /boilers and engines for the last 40 years and to date I haven't ever seen a boiler explode even some boilers that I would refuse to test but for your own peace of mind get it certificated and go out and enjoy sailing your launch.
George.

P.S.
 Please put some threads on George, here is a couple of pics showing the hull condition after 45 years



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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #69 on: November 24, 2011, 09:51:20 am »

Hi George,

She's in beautiful condition for a 45 year-old!  A very nice model.
The epoxy skinning really seems to work well - since I skinned the vintage launch by way of experiment some seven or eight years ago it has stood up to a relentless yearly regime on the river and never given any problems - i trust Natterer will be the same.

Regards

Ted
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #70 on: November 25, 2011, 01:37:44 pm »

Moving on!


‘Natterer’ – A shipbuilding Odyssey? – Part 14

The major item on deck has to be the casing over the boiler.  I first attempted this in aluminium, but found I could not satisfactorily rivet the thing together, so had to resort to brass sheet again and accept the weight penalty.  The casing is screwed to the deck, and carries the funnel on a foundation ring, again in brass.  The funnel you see is actually a sham, as the heat from the boiler acting on the white-painted funnel would have soon discoloured the paint, and that wouldn’t have done for the proud owner of a steam launch!  Inside the outer funnel there is an inner funnel, slightly smaller and shorter, which carries the actual nasties.

The wheel is loosely based on Bat’s, and was formed with a brass rim, pierced for turned spokes, all assembled into a hub.  The wheel and chains turn, but are not connected to the steering – I had to draw the line somewhere!

The concoction sitting on the boiler casing that looks a bit like a tea urn is actually a Windermere Kettle.  A lot of the Windermere launches carry them to provide boiling water to make tea to go with the sandwiches and cream scones which were de rigueur at this time (and still are!).  Basically a copper can in which a coil of copper pipe is wound.  Steam from the boiler is passed through the coil, and heats the water in no time at all.  The kettle on Natterer does work, but I don’t use it as I haven’t yet figured a way to connect the kettle and still allow the deck to be removed!  (Anyway, it doesn’t provide enough boiling water to give me a decent mug – sorry – cup of tea – our Victorian ancestors wouldn’t use such a vulgar word as mug when partaking of the pleasures of a sail on Windermere)

Finally, the pressure gauges, whistle and safety valves are not attached to the deck or casing, but are fastened to the power-plant and protrude through suitable openings in said deck and casing.  I had thought I might like to exhibit the launch if it turned out well, preferably with the power-plant alongside, and you may also remember I had the facility to run the launch under electric power alone.  Both these requirements meant the gauges, whistle and valves would be missing from the boat, and so a duplicate set of valves and gauges was made up on a panel which can be readily bolted with one bolt to the underside of the deck, thereby making Ted happy again.

A grating was built to cover the burners, which obtruded slightly into the forward passenger well, and bottom boards and seats were made up.  Various pieces of brasswork in the form of bollards and fairleads were scattered around, and steamed curved coamings were fastened on the front and rear of the cockpits.  Finally a suitable twirly thing to go on the end of the propshaft was procured from the Prop Shop, who cut down a 5” prop to 4.5” for me; Diane Carney of steam-engine fame provided etched nameplates, and Mike Allsop (Scale Flags and Ensigns) painted a super-size red ensign for me.
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gondolier88

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Re: Natterer - A shipbuilding Odyssey?
« Reply #71 on: November 25, 2011, 02:16:21 pm »

A real work of art Ted, you can be justly proud of the detail you have put into this model. It's so refreshing to see a Windermere boat modelled as a Windermere boat was built.

The boiler casing is beautiful, in reality full size, if the boiler casing had been made in brass it would have been left bright, I may have been tempted to keep it that way on the model too. Indeed, Alfred Sladen's next boat after Bat, Otto (although named differently at the time he designed and owned her), had an all brass funnel that was kept polished at all times. Only a little detail that I noticed in a very old description of her, and at the next opportunity I got I scratched the paint on the funnel on Otto fully expecting to find a steel replacement, but instead found brass, to which it will return. The rivetting is superb too- I can't see a head out of line or mis-shaped.

On top of that, a WORKING steam kettle!!!

Would you ever consider making another Windermere boat?

Greg
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Don't get heated...get steamed up!

thelegos

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Re: Natterer - A shipbuilding Odyssey?
« Reply #72 on: November 28, 2011, 09:51:25 pm »

Hi Ted, thank you again for sharing your work, excellent as always plus a glimpse of your good self in action!! I'm glad the rudder information was of interest.
Roger
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Ted Welding

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Re: Natterer - A shipbuilding Odyssey?
« Reply #73 on: November 30, 2011, 05:51:12 pm »

Hi Roger & Greg,
Many thanks for your further kind words - it's what makes all this work worthwhile!
I did consider leaving the boiler casing bright, but then thought about the cleaning, and quickly changed my mind!  The funnel is aluminium, so no opportunity there either. 
I did think about 'Branksome' as a possible project, possibly utilising the same boiler/engine, so I could drop the plant in to either.  Unfortunately, at the same scale as 'Natterer' she would come out at about 10' long, so swiftly dropped that idea.  Anyway, I don't think I would want to commit myself to the amount of time it would take.  I've just started to build a model of 'Kingfisher' in full frame, so that will probably take me a few years!  ('Kingfisher' - A swan class sloop of war of 14 guns See     http://www.google.co.uk/imgres?imgurl=http://collectionsonline.nmsi.ac.uk/grabimg.php%3Fkv%3D184337&imgrefurl=http://collectionsonline   )
As regards Kitchen rudders, I think I might just return to them again next year!

Anyway - on to part 15 of the 'Natterer' story.


 ‘Natterer’ – A shipbuilding Odyssey? – Part 15

There is a lot of debate in model boat circles as to whether a crew should be included on a boat.  My own view is that an open launch such as Natterer looks daft sailing without a crew on board, so something had to be done.  You will recall that the scale of Natterer is 1 to 4.5: this meant the average adult scaled down to around 16” (400mm) Now although I think my modelling skills are reasonable, there was no way I could produce figures at that scale and have them look remotely realistic.  So I had to look elsewhere.

After a lot of searching, I eventually found Shirley Nason, of Kent Garden costume Dolls, who was prepared to produce me a couple of dolls dressed in late Victorian costume.  It was an interesting experience as the two fields of model boats and costume dolls don’t often cross, and Shirley had her own way of doing things which didn’t always chime with mine!  For example, Shirley’s dolls use bisque heads and lower arms allied to a body which is basically a rag doll.  The dolls are traditionally displayed standing using a frame, and the lower legs (also in bisque) are hidden and tiny (No – I haven’t a clue why – they just do it that way!).  My problem is that the crew had to be sitting down with feet showing, and the concept was alien to Shirley.  We came to a compromise in that Shirley produced the dolls in the traditional way, and sent me the feet from a larger doll, which I grafted on.  I then stripped the dolls of their clothes and modesty and produced an aluminium frame to which the body and extremities were sewn so that I could pose the dolls as necessary.  This worked a treat, and the dolls now sit in the boat by means of a spike emanating from somewhere the sun doesn’t shine, to allow me to fasten them in when sailing.

The clothing Shirley produced was exquisite, and included all the embroidered underclothes, even down to the detachable bustle under m’ladies skirt!  We had some problems with the father, as we couldn’t find a suitable male face, so ‘he’ is actually a ‘she’, with the addition of a set of whiskers.  I won’t go any further down that route!

So good were the figures that we commissioned a further two from her, depicting a couple of children, who sit and stand in the front well, because the young lad won’t behave himself.

I probably can’t do better than reproduce the information given on the display card that goes with Natterer when she is on display:

Crew: Father is so proud of his new toy, and the opportunity to show it off, totally ignoring his rather apprehensive wife, who worries about her two children in the bows and the whole idea of boating. The son won’t keep still, and has to see where they are going, while his sister, who disapproves of everything her brother does, appears not to be enjoying the experience at all. Figures all by Shirley Nason of Kent Garden Costume Dolls.

Sadly, Shirley was getting on, and these were I think the last dolls she produced before having to give up commissions in order to look after her ailing husband
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rmaddock

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Re: Natterer - A shipbuilding Odyssey?
« Reply #74 on: November 30, 2011, 08:18:47 pm »

I know others disagree Ted, but I think the dolls are wonderful!
I don't think the fact that they are obviously not "real" detracts at all. Rather, it adds to the charm.
They also remind me of the sort of very genteel children's television programmes  on which I was raised.  I can just imagine the nice lady's voice narrating the not-at-all-animated story of the family of dolls as they have adventures here and there. :embarrassed: I imagine that they frequently had problems with a tear-away teddy bear.  %%
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