Small Oscillating engine with gear box.

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well ok then. I thought you had gone to the proverbial dark side and purchased a 3d printer.


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:

Regards Tony.
Another fantastic build tony thanks for sharing.
Hi Tin,

Well OK then. I thought you had gone to the proverbial dark side and purchased a 3D printer.

Alas no I don't have the ability! Our son made one and his children use it to make name badges and the like. It is easy Granddad all you do is........

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As can be seen the whistle has been replaced by a top-up valve and the exhaust connected.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.
Alas no I don't have the ability! Our son made one and his children use it to make name badges and the like. It is easy Granddad all you do is.......

Well just maybe you can get the grand kids to print you some gears. It is quite easy. I started a thread here as to not side track this one.Plastic Gears Thread

Hi Tin,

Well just maybe you can get the grand kids to print you some gears. It is quite easy. I started a thread here as to not side track this one. Plastic Gears Thread

I had a look very interesting I wish I understood it. We see our grandchildren in a couple of weeks I will ask them.

Hi David,

Looking at the photos of the hull construction, I see what appears to be a second layer on the bottom. Did you double up the bottom?

I cannot see what you mean which photograph? The hull bottom is just a piece of 1/4" spruce wall cladding.

I thought you might appreciate the name as it is white and has a fire, it is also our eldest granddaughters name and the Anglicized version the title of our son's company.

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.
That should move along nicely. Great video and looking forward to seeing it in the water.

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.
Looks like you have enough grunt there to tow half a dozen water skiers :D

I have been into town to get some R/C gear from a model shop and on returning home set about fitting it into the hull. As for the moment the R/C will be for rudder only and space is a bit limited a box for the R/C was made.

All the R/C gear fits in the box, which will give limited protection from water.

The weight of the batteries etc. will replace some of the lead ballast, the R/C box is held into the hull with a couple of brackets.

The rudder fitted.

The model is now about ready for checking out. A tank for the waste oil still has to be made and a box to transport the will also have to be made. So with a bit of luck and good weather it shouldn't be long before the model has its maiden voyage.

Regards Tony.

In theory the model is ready for its maiden voyage. A tank for the separated oil has been made and fitted, it will be empted using a syringe and the hull has been re- ballasted to compensate for the weight of the R/C. I am in the process of making a box to transport the model in.

Regards Tony.

Yesterday I had the opportunity to try out the steam model of a Murray River Paddle boat I made in a very small boating pond. A video is at:

I was quite pleased with the result as I have never made a model paddle steamer before. The model has a reasonably small turning circle but the paddles do not seem to absorb much of the engines power so I am wondering if larger or more paddle blades would improve its performance. Any suggestions? Maybe for the models next run I will try with the existing paddles lower in the water.

Regards Tony.