Alternative Tin
If you cannot obtain the sweet tin in your part of the world, a large fruit or soup can can be used.
This will be about 100mm diameter. This is what was used in my original Tin Can Engine
Following some request to make a video of how it is made I have found that local supermarkets now only have tins with ring pulls.
The description below will only work with a tin that needs a can opener.
See further down the page for how to make one from a ring pull can.
Non ring pull can.
Using a can opener ( the type that cuts of the top and leaves the top smooth and the can sharp) remove the top of a fruit can. Eat the contents!
If you cannot obtain the sweet tin in your part of the world, a large fruit or soup can can be used.
This will be about 100mm diameter. This is what was used in my original Tin Can Engine
Following some request to make a video of how it is made I have found that local supermarkets now only have tins with ring pulls.
The description below will only work with a tin that needs a can opener.
See further down the page for how to make one from a ring pull can.
Non ring pull can.
Using a can opener ( the type that cuts of the top and leaves the top smooth and the can sharp) remove the top of a fruit can. Eat the contents!
Cut the can on the second corrugation up from the bottom at the point shown below.
This should make it about 33 mm tall.
Cutting in the correct place will allow the Inverted top of the can to clip neatly over the corrugation and can be sealed with silicone.
If the can has a ring pull opener 2 cans will be required, you will need to use the bottom of the second can as a lid. More care will be needed when sealing the engine parts to the can as the top will be corrugated and not flat like the sweet tin.
If the can has a ring pull opener 2 cans will be required, you will need to use the bottom of the second can as a lid. More care will be needed when sealing the engine parts to the can as the top will be corrugated and not flat like the sweet tin.
I used a revolving cutting disc mounted in the drill press and held the can firmly down on the table whilst rotating it against the disc.
This method also allows you to gradually reduce the height until the top fits correctly.
CUTTING THE CAN
Great care should be taken when cutting cans. Gloves and eye protection should be worn.
The thickness of the balsa displacer should be adjusted if necessary so that when the flywheel is turned it nearly but not quite touches the top and bottom of the can. The diameter of the displacer should be about 6mm less than the tin diameter, it must not touch the sides of of the tin.
Using a ring pull can
Extra care with construction will be needed with this option as the top of the tins have corrugations. Where the base of the engine fits it will need extra silicone to ensure an air tight seal.
Beware too that there will be sharp edges on the lid.
Alternative Displacer Construction.
Some builders have mentioned that they are unable to buy balsa wood where they live and have asked what could be used instead.
Balsa is an idea material for this simple engine as it is dense and light. It will fall under its own weight and being light can be raised by the small amount of power that this engine produces.
It has been asked if polystyrene foam could be used but as the engine will get quite hot I don't think this material would survive the heat.
The alternative shown here is made of cardboard and is protected from the heat by a wrap of aluminium foil. This has proved to work well and weighs exactly the same as the balsa one. When fitted with the displacer rod the weight is 12 grams.
Care is necessary when making this one as it is essential that the hollow construction is completely airtight or the engine will not work. This is why the fillets of adhesive are added when assembling the card, they give a larger area of adhesive.
If you cannot get the diaphram to move when the displacer is manually moved up and down as shown in this video, another possible cause would be a leaky displacer. With the balsa one this problem would not occur.
