Murray River Paddle Steamer.

[Tony Bird]

Hi,

Today I did some more painting and made a paddle wheel from some 1/16" aluminium sheet.










Regards Tony.

[Delaunay]

  Hello ;

Why complicate things when simplicity works too

cordially

François

[Tony Bird]

Hi,

Completed paddles.



Regards Tony.

[Tony Bird]

Hi,

I did some more on the paddle boat today.  I have decided it is as far as I will go with the painting, it could be a lot better, arthritic hands don't help when sanding!

A drip tray for the engine.
 


A simple stand was made.



The paddles and engine fitted.



The paddle boxes fitted.




It has been run on air again a video is at:

https://youtu.be/xUkX8HcZXmQ

Regards Tony.

[Delaunay]

Hello ;
Small wheels just waiting to offer this boat for large shipments! 
cordially
François

[Tony Bird]

Hi,

I did some work on the boiler today.  The boiler was intended for a boat and it was built a few years ago.  As designed the steam was going to a reversing valve/regulator before going to an engine so the boiler has no regulator fitted.  The boiler is a pot boiler with heat exchanger pins and can be fired by Sterno or a ceramic gas burner.

A constructional photograph of the boiler showing the pins steam pipe and where the steam is collected, the steam dome when fitted holds the condensing chimney.



The boiler and its Sterno tray before any further work was done on it



As the engine is a single acting one and won't self start so there is no point in fitting a reversing valve.  If the model boat had been screw driven like a lot of the model steam boats made years ago by the likes of Bowman a regulator needn't be fitted.  But as this is a paddle boat I thought it might be wise to fit a regulator to try and get the best out of the paddles, it might turn out not to be necessary.



As the boiler looks in the hull.



As can be seen the whistle has been replaced by a top-up valve and the exhaust connected.  A lubricator needs to be made and fitted and the boiler secured in the hull before a steam test can be made.

Regards Tony.

[Tony Bird]

Hi,

A lubricator was made and fitted today.  I am not very keen on lubricators that have a drain I prefer them that need a syringe to empty them as they are not as messy to empty.  To allow the syringe draining tube to pass the steam pipe it is off-set when it goes through the reservoir.  This is easy to do as long as the tube to be drilled has been plugged with wood.  An undersized hole for the steam pipe is drilled in the reservoir at right angle to the tube, while the drill is still rotating in the tube is turned so the drill is at a tangent to the diameter of the tube.  The tube is then plugged with a hard wood and the exit hole for the steam pipe is drilled this pilot hole is then drilled to the size of the steam pipe.
   


The steam pipe marked with the position of the hole.



It can be difficult to drill the small hole in the steam pipe especially if it has been annealed.  What I do is to use a small round file to file part way through the steam pipe a the use a n old gramophone needed held in a pin vice to make the hole.  Sewing needle would probably also work.  Sorry it is a poor photograph of the result.



To insulate the boiler from the hull the modern equivalent of asbestos was used; it is the fire retardant material used as eves in houses.



This board was cut slightly smaller than the base of the boiler and cooking foil was attached either side of it.



Some brackets were made to hold the boiler in the hull.



The boiler was fitted into the hull and connected to the engine.





The engine has been steam tested with the boiler fitted in the hull,  I will post a video of it running when it has been down loaded.

Regards Tony.

[Tony Bird]

Hi,

A steam test video at:

https://youtu.be/jiSNmjoM6Fg

Regards Tony.

[Tony Bird]

Hi,

Today I had to get one of my larger engines ready for its 4 year hydraulic boiler test which hopefully will be done this Saturday at the CMES.  That took most of the morning then we then had a phone call inviting us out to lunch, which was very nice so I have only had an hour or so's playing with the paddle boat.  I decided to give it a run in a test tank (plastic box).  First the hull was ballasted to its water line.  Paper templates were used and lead sheet cut to them.
 


Two sheets of lead at both bow and stern were needed to get the hull to its water line.



The boiler was fired up and the engine ran in the plastic box.  Every thing seemed to work well and the engine under load was very controllable.



I am not sure how far the paddle blades should go into the water they are ballasted to about about half their depth at the moment, even with the blades completely submerged the engine coped with the extra load easily.



The video will follow when it is down loaded.

Regards Tony.

[derekwarner_decoy]

Well congratulations Tony on the first water test & all appears fine 

We must acknowledge the speed of progress on this build has been nothing but outstanding 

With respect to paddle blade immersion, most vessels appear to have the 6 o-clock blade under water with the next blades [toward 5 & 7 o-clock] just licking the water......however naturally your first river tests will dictate this

Will you be installing R/C equipment, or will she be a straight runner?

Looking forward to seeing the video.......Derek.....

[Tony Bird]

Hi,

Video at.

https://youtu.be/Nx-TX9uo710

Rudder only R/C to be fitted.

Regards Tony.

[DamienG]

Looks really nice Tony. 

[Tony Bird]

Hi Derek,

With respect to paddle blade immersion, most vessels appear to have the 6 o-clock blade under water with the next blades [toward 5 & 7 o-clock] just licking the water......however naturally your first river tests will dictate this

Thank you for this information which seems logical.  This is the first model paddle driven boat that I have made.  The drawings that I used as the basis of my model showed the wooden paddles used as so:



In the text with the drawings the designer said that it was his first effort at making a paddle drive model.  The model worked though its designer mentioned the paddles threw up a lot of water.  I didn't fancy making a similar design in metal, hence my design.  I used 8 blades rather than the 12 on the drawing because with the construction used it wouldn't be easy for a Pop riveter to get between the blades if 12 were used.  With the information you gave me I did this drawing of the 110 mm paddle wheel used on the model.



It would appear from the drawing that the lesser number of blades that are used for one revolution of the paddle wheel more water is moved?  Is it known if this is a fact and benefit for use on models?  Also is there any point in the blade being any higher than the maximum depth that it goes into the water?

I am fitting R/C into the hull, initially rudder only.  This hull will be used to try out different ideas regarding boiler, engine, gear box and now perhaps paddle design.  I have already cut out materials to make another hull of similar design which I hope to fit the results of my experimentation to and it will have a superstructure similar the the original design.  When I have fitted the R/C gear I hope to try the efforts so far made on the water proper.  This might be some time happening but I will report the results.

Regards Tony.

[derekwarner_decoy]

Evening Tony......there are so many variables with paddle design & enough to complicate any build even if producing a paddle wheel set that is/are scaled on the original full size build

Scale, paddle wheel diameter, number of blades, immersion depth, height of blade, width of blade & paddle shaft axis speed

Working backwards, model paddle shaft axis speed should be the real ship shaft RPM x by the cube root of scale....this is the only scientific or mathematically valid unit of input in the calculation, and even this negates the fact that we cannot down scale the surface tension of water

Over the past years of this WEB site, we have taken a rather conservative attitude with paddle deign & speed and have generally considered using prototypical wheel scale dimensions and coupled with the calculated scale paddle shaft RPM as a starting point

Many builders have considered scale like wheel dimensions as more important than wheel to vessel performance, however by using a form of variable paddle shaft RPM to compensate for any shortcomings

So varying any of the paddle design or dimension elements will invariably alter the wheel performance

The proposition you put forward re the number of paddle blades is only relative to the depth of immersion....

8 blades *16 depth = 128
12 blades *8 depth = 96
however
12 blades * 16 depth = 192

So from this, I am not suggesting any design element is not correct, it is however more of a trial and error on the water to understand a vessels performance to expectations

[I have a long suffering paddle steam build....a hull I drew the plans for in Y2000 & a build that will eventuate]

.....& keep us posted with your progress........... Derek 

[Tony Bird]

Hi Derek,

Many thanks for your answer, it certainly looks as if it is a bit suck and see.  My point with the drawing was given the same criterion 'With respect to paddle blade immersion, most vessels appear to have the 6 o-clock blade under water with the next blades [toward 5 & 7 o-clock] just licking the water'. that a smaller number of blades appear to move more water.

Your engine for your boat looks wonderful much better than I could achieve.  I will need to go into the city to get some R/C kit before any more progress can be made.

Regards Tony.