Search results

Sadly there are only two practical alternatives to making a cam: use a sleeve valve (which has its own issues, to say the least) or build a 2-stroke (and they are the work of the devil). So we must grit our teeth and persevere. Something to consider for future engines is that it's common for...

As an alternative suggestion, maybe you could try using a diamond tipped hole saw to cut the circles? The main thing to watch out for in that case would be that you need constant flood cooling (both to keep things cool and carry away the glass dust) and you should cut only part way through from...

I just get the right grit of silicon carbide powder (sold online for lapidary use) and mix with oil.

Hi Brian, I often use a set of parallels to align flat parts in the 4 jaw. You just put them between the part and the chuck. One can center on a hole at the same time by placing the point of a dead centre in the hole, and supporting its tail with another centre in the tailstock, then indicating...

Lovely, those fins really do add to the look of the engine. If you have to do a lot of parts like this, it might be worth getting multiple saws and ganging them together on your arbor. That's how they did the cooling fins on old radial engines, presumably with some interesting fixtures!

Rotten luck with the bad knees. A lot of my family members are afflicted with a genetic disease that means some of them need artificial joints (ankles, knees and hips) by the time they are in their 20s, some others last a bit longer but they all go wrong well before their time (thankfully i...

Regards ignition timing, for an inline twin there are three popular crankshaft designs: 360 degree crank, the crankpins are in line with each other and cylinder 2 fires 360 degrees after cyl #1. This results in even firing with 360 degree intervals, but the crank has the same dynamics as a...

Briggs and Stratton has been building engines with aluminium bores and pistons for decades. They chrome plate the pistons to prevent seizure under load.

Another belated update. I've been busy tinkering with my new mill, notably scraping in the vise and knee gib, and making a 22mm horizontal arbor. The reason for the latter is that I was very spoiled this Christmas, and I'm now the proud owner of a vertex BS-0 dividing head. It's very nice, and I...

I've always thought that T-heads managed to incorporate the worst of both sidevalve and DOHC into one design. Doubtless the engine will low powered, inefficient, and have dirty exhaust by the standards of a more modern design style. But that doesn't matter much for a model that just idles a few...

New (old) milling machine! Sadly my Atlas had to move to a new home to make room, but I'm very pleased with the Hercus. It's quite a bit more substantial than the Atlas, so I can take much heavier cuts. Pity about the lack of power feed, but I rarely used that anyway. I'll need to re-tool, so...

Could you make three separate distributors, one for each bank? This would surely be easier than a single distributor managing all 18 cylinders.

Regards superheated steam, you also need enough expansion ratio (and a low enough exhaust pressure) to make use of the extra heat. Coming from the infernal combustion side of things, a typical ICE hasn't got enough expansion ratio to fully utilise the heat in its combustion gases, the exhaust...

Wow, more than a month since I last updated! My replacement engine block is almost done. However, another complication has arisen: after an engineering consultation (my dad looked at my drawings while I was away) I've been informed that my main bearing mounts need revision, the 4 M3 screws each...

It will work, but there probably won't be any advantage over a single of the same displacement.

I'm wondering what people use as 'washes' to fill in the gaps in the sand of cores and moulds, in cases where a fine finish is needed, or to prevent sand 'burning on' to the surface of the casting. Any suggestions?

Ductile is less slippery than grey iron, so grey would probably be better for the liner. I just already had ductile iron the correct size. I wouldn't use bronze for the piston skirt, it's very heavy! An aluminium skirt should be fine against chrome molybdenum steel, thousands of aircraft...

Cylinder liner: ductile iron, grade FCD450 Piston: cast aluminium, grade AA337 (9.5% Si, 3% Cu, 1% Mg, 1% Ni balance Al) Rings: grey iron, grade FC250. The rings are 1.15mm thick, except for the oil control ring which is 1.5mm. I have an unhealthy habit of using FCD450 for almost everything...

Yes

Made the piston rings and fitted to the piston.