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A simple turning job from brass, face off, drill 2.0mm and part off to 2.0mm thick


I did not have any 5mm square stock so milled down the end of a round bar and while in the indexer drilled and countersunk the 2.0mm hole then rotated it 90degrees and used a slitting saw to form the slot. Then into the lathe to drill 1.6mm and tap M2 before parting off to length.


Another simple turning job. Make sure the head is small enough to fit just below the surface of the follower fork.

You will also need a small dia spring to slip over the valve rod, about 20mm free length, 0.5mm wire. Does not need to be too strong as that will increase the load on the engine - just enough to keep the follower in contact with the cam


Face off the end of a piece of cast iron , turn OD down to 28.0mm and then part off a 0.5mm thick slice, if your parting tool leaves a pip in the middle don't remove it.

The eight sides that form the octagon can just be filed but make sure you leave a small part of the 28.0mm dia edge between each as it will help keep the valve centred within the base. The valve can then be lapped on some 1200g wet & dry using a disc of metal to keep it flat; this is where the pip helps.

Parting off will leave the valve slightly concave so you only need to lap the edge as can be seen by the polished area.




Part 9 by Jason Ballamy



This is silver soldered together from the three parts shown. The main tube has five holes drilled 0.5mm dia at a spacing of 4.0mm starting 5.0mm in from one end. This end has a small plug soldered into it which can be turned or a brass rivet can be used. The other end will depend on the gas hose that you have. Mine needed a hole to take a 6mm O-ring seal and threading M7 x 0.75 for the union.


I chose to use a casting but you could machine one from solid. There are several suitable sized flywheels about, this one came from Reeves and is their Perseus one. RDG do a part machined one and there are a couple of e-bay sellers that have flywheels, too. Final dia and width of rim are not critical so just machine off enough to clean up the surfaces as any extra weight will help with smooth running.

If you have a small enough boring bar then use that to take the bore to final size from say a 5.5mm drilled hole if not drill and ream. Add a M3 cross hole for a grub screw to retain the flywheel.

Well, that's about it as far as construction goes. The cam should be adjusted so that the intake port is just starting to open as the crank pin reaches the 5 o'clock position when viewed from the shutter side and should be closed at about 11 o'clock. If all is right the engine will turn easily in the clockwise direction and make the farting noise as the piston descends but if turned over anti clockwise should be quite hard to turn as the piston comes up. Correct running rotation is clockwise when viewed from the shutter side.

Once the flame is lit the engine will need flicking over a few times to warm it up and will slowly start to run for a bit longer after each flick until it reaches a point where it will continue to run. You may have to play about with flame position to find the sweet spot and position can also be used to alter speed as can size of flame. The bearings, big and little ends can have a small amount of light oil but the piston can be run dry or if you feel the need apply a little WD40 (not while flame lit!)

I used a couple of colours of stove paint on the engine, which does get hot, so whatever you use should be heat resistant. A round wooden base can also be easily made on the lathe and gives somewhere to screw the burner support.

Part one here  Part two  Part three Part four  Part five  Part six Part seven Part eight

Part nine




A simple turning job. Face off the end of a piece of 10mm dia brass, use a small round nosed tool to add the decorative moulding, drill 3.0mm and part off to 2.0mm thick


Face off the same bit of 10mm brass and then over to the mill to cross drill the 5.0mm and 3.125mm (1/8") holes at right angles to each other. Back into the lathe and drill and tap the M3 hole before parting off.


Form a decorative end on a piece of 5.0mm dia brass which can be done with a form tool of freehand and then refined with a file. Part off to length, reverse in chuck and drill and tap the bottom M3


reduce the end of an 8mm piece of brass down to 3.0mm and thread M3. Then form an oval end again with a form tool or freehand. Over to the mill and cut 2.5mm off each side. -

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