5 Cylinder Radial Engine (TECHING) - EngineDIY

[James H]

1:6 Five Cylinder Radial Engine (TECHING)

EngineDIY

Catalogue # 33ED3355414

Available from EngineDIY for $469.99

 

C. M. Manly constructed a water-cooled five-cylinder radial engine in 1901, a conversion of one of Stephen Balzer's rotary engines, for Langley's Aerodrome aircraft. Manly's engine produced 52 hp (39 kW) at 950 rpm. Most radial engines are air-cooled, but one of the most successful of the early radial engines (and the earliest "stationary" design produced for World War I combat aircraft) was the Salmson 9Z series of nine-cylinder water-cooled radial engines that were produced in large numbers. Georges Canton and Pierre Unné patented the original engine design in 1909, offering it to the Salmson company; the engine was often known as the Canton-Unné.

 

The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders"radiate" outward from a central crankcase like the spokes of a wheel. The pistons are connected to the crankshaft with a master-and-articulating-rod assembly. One piston, the uppermost one in the animation, has a master rod with a direct attachment to the crankshaft. The remaining pistons pin their connecting rods' attachments to rings around the edge of the master rod. Extra "rows" of radial cylinders can be added in order to increase the capacity of the engine without adding to its diameter.

 

The kit

A 1:6 engine comes in quite a large box, as I soon realised. Actually, it's a very high quality tin, with a lid that lifts right off to display an instruction manual sitting between two pieces of protective foam. The lid itself shows an illustration of the completed engine, while the side has the kit-specific details. For an idea of scale, I've sat my Swann Morton retractable scalpel on the kit. There's a reasonable amount of weight in this kit too...approximately between 1.5 and 2kg. No surprise as this kit is 99% metal. The side panel of the tin gives a few more details.

All of the parts in this kit are recessed within sturdy foam trays that also have the part numbers engraved into the foam, adjacent to each part. This makes it ridiculously easy to find exactly what you need in each stage. There are FOUR trays of components in this kit. While there are are a number of electronics parts, with the exception of these and the plastic cylinder head rockers, everything is in cast or machined aluminium etc. 

 

You'll notice the white plastic box in that tray. That's choc-full of screws, turned parts, springs, bearings etc. Each little section is padded with some foam. Again, there's no lube in this box. It must be something they had to leave out for some reason. Quite add as the kit contains another contentious item....a lithium battery.

 

 

 

 

 

[James H]

The lack of lube in the kit meant that I needed to buy some. I opted for this stuff, and used cotton buds to apply to the various connections. The manual us very clear about where lube is to be added, and this generally centres around the pistons and crankcase...not inside the piston heads.

Piston assembly is very easy. All you need to do is to sit the linkages into the piston head and then insert a pin which is then locked into place by two circlips. As with the real engine, one of these has a master rod which connects to the crankshaft and does NOT articulate. Here, that is the second from the left. You can see a section machined out of the base which then is pinned to the crankshaft. The others will articulate.

The crankshaft now sits within the crankcase. I add a little lube to this. 

This part is then added to the crankshaft and provides the base onto which the pistons will fit. This is supplied with a small bearing that neatly pushes into it before assembly. The pins you see are for locating the pistons into the recesses in the assembly.

There is one task in assembling this engine, that could drive you to distraction, and that's adding the pistons. Without a doubt, this is awkward as there are five of these which will persistently try to fall out as you add the next. The best way to do this is to sit the crankcase into one of the cutouts in the foam parts tray and then carefully prop up each of the piston heads so they don't fall away from the centre of the crankcase. When you have them all in position, you can then add the linkage cap and screw it into position. This stage feels like a real achievement. 

This crank can now be fitted into place.

This is a working model, so a little cheat needs to be fitted, in the shape of an electric motor which will drive the gearing. This is also very nicely hidden when complete.

The completed rear crankcase now now be screwed to the main casing. One thing the manual does not make clear is that the motor needs to be adjacent to the stand connection on the main crankcase. I did fathom that out, but I have seen at least one video where a builder has a wire stretched around the back of the crankcase, down to the stand which contains the battery. The motor is then covered over.

[James H]

If you see any black flecks as are visible here, these are just some debris from the foam trays. Parts with this are just blown clear before assembly. Here are the cam and gear which are simply fastened with four small screws.

The cam drive gears are now selected and assembled as shown. You'll notice the mounting pins are machined to accept the gears. The gears must also be fitted in the orientation shown in the manual.

Yes, you see that correctly....a metallic red prop! Whilst I understand that it's better to include a machined metal prop as there won't be any balance issues, I might well have selected a different colour to anodise it. Still, this is a display model and it does looks strangely attractive when fitted. Here you see the prop and the front crankcase with the bearing, collar and prop hub parts.

Now it's onto the rocker arm assemblies. It's here you'll find the only plastic parts of the engine, seen here in black. The quality is still excellent and these parts aren't at all fragile. 

We turn our attention to the five cylinder head assemblies. Lots of screws to use here and you can see the exhaust ports and valves here. The valves do actually work too.

The rocker arms are now fitted to the top of the valve assemblies, and little reproduction spark plugs added. You could choose to paint the insulators in white, but I opted to leave in natural metal.

The cylinder blocks themselves are now fitted to the completed cylinder heads.

[James H]

 

Here is the main event! The model is actually quite large and weighty, and we haven't finished yet. The ejector rods and sleeves are now to be fitted. This is done one cylinder at a time, and needs to the rocker arms to be lifted to allow the ejector rods to sit.

 

 

The base is now fitted, and a spacer mounted between the base and engine. Once fitted, the battery charger port, switch and motor cables are threaded into the base. The cables are then plugged into a control board, along with a battery pack. The circuit is then screwed into the base and a cover fitted to hide it all. The kit also includes a USB charging cable too (not shown).

COMPLETE!

And here is a video I made of my review build.

 

 

 

The instruction manual is clearly illustrated and the average builder should find zero difficulty in following each stage.

Conclusion

I didn't know what to expect before seeing this kit in the flesh, and I was very pleasantly surprised. I'd had a hankering for building something like this for a while, but I suspect the mixed reviews I'd seen were from cheap copies. This kit very much surpasses my expectations in presentation, quality, and also the final result. This model took me about 5hrs to complete, but that's also because I was setting up photos of each stage. I think it's fair to say that the manufacturer expectation of about 3hrs is reasonably accurate. The instructions are very easy to follow and should present no problems, even to a beginner who has no sort of modelling or engineering experience. All parts fit perfectly together with no issue. The only things I would criticise are the hex keys which are a little soft and round off easily, making tightening the screws hard. Also, there is no lube in this kit any longer, so you will need to source your own. In all, a fantastic kit.

 

My sincere thanks to EngineDIY for sending out this kit for review on Large Scale Modeller. I'm more than sure you'd really enjoy this one. To buy direct, click the link in the header of this topic.

 

 

 

[James H]

Oh, and if anyone wants one, I have a code that I'm told will give 16% off.