I remember seeing the Alyn Foundry CHUK range of flame licker engines and quite liked the look of them but as I was engrossed in building my Fowler traction engine at the time did not have the need for more engines. Recently, despite the demise of Alyn Foundry, I was able to borrow the build notes that came with the engines, these combined with looking at photos, and a bit of artistic license, allowed me to come up with the design shown below. Despite what some people say, if you want to make an engine enough you don't need dimensions on every feature to copy.

I have made a few engines recently with a 24mm bore which I find quite a nice size as they are not too big to handle or display and there are no large bits of metal needed that will break the bank. So this engine also has a 24mm bore which makes it about 2/3rds the size of the original CHUK, stroke is 32mm and the flywheel is 102mm dia and also the only casting used but at that size could be fabricated quite easily. I have tried to add a bit of shape to the parts so that they look like they were made from castings rather than make just another bar stock engine.

The work is mostly milling or turning from solid although there are two items that will require silver soldering, even then one could probably be done with some small CSK screws if you don't fancy soldering. There are also several parts that need lapping, the flat ones can be done easily enough on a flat surface with fine wet and dry but the cylinder also needs lapping as does the piston.

Click on drawings to download - for personal use only.


This can be made from a slice of 75mm or 3" dia aluminium or could even be done from some 12mm plate. I started with a slice of round bar, held in the 3-jaw to face off and then bore the 28.5mm hole right through. I also removed some of the waste by turning a 60mm dia spigot.

The spigot also made it easy to hold the base the other way around to face off the bottom.
The base can then be mounted on the rotary table and clocked in true to the spindle to start shaping the raised area. I used an old 10mm dia milling cutter with the corners ground off to a small 1mm or so radius so that it left a fillet as you tend to see on castings but it could be left square if you prefer. Start by cutting in from one side until the face is 21mm from centre.
Next cut the two sides, I have shown the point where the 10mm cutter should stop at 22mm in the Y axis and 13.86 in the X axis.
The table can now be rotated to reduce the rest to 42mm dia.
Next add the decorative moulding to the edge, an old 6mm dia cutter can be ground by hand either on the corner of the bench grinders wheel or with a dremel which will give an acceptable shape.
While held like this the Hole for the chimney can be drilled 9mm and then tapped M10x1, if you don't have fine pitch metric taps then 3/8" ME threads would do.

The base can now be held upside down in thevice with teh flat edge against the fixed jaw, clocked central to teh spindle and the four M3 clearance holes drilled, I tend to use 3.0mm drills for this as teh socket head CSK screws tend to come in at about 2.8mm OD. I won't keep mentioning it but ease the edges of all holes either with a CSK bit or a lathe tool ground at 45degrees, you will often see these tools in the photos as it it the last op before taking the pic.

To mill the exhaust passage I dusted off the swivel base for my vice which was the first time I have used it in the 10yrs since I bought it, set the vice to 45degrees and then with an 8mm cutter cut the slot 3mm deep . If you don't have a swivel vice base then the base can be clamped directly to the mill table and the angle is not critical.
Thats the first part out of the way.

Part two here




Part 1 by Jason Ballamy


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