De Industrie 2VD5

[Richard Hed]

Richard, I did not find this on the scrap yard, but bought it brand new at a model building shop (costs about 1 Euro/Dollar per cm/half inch). However, the scrap yard is indeed a very good source for these tubes, but you have to be lucky to find them in time before they are cut/bend or thrown into a large pile.

The ID is extremely nice regarding size and surface finish. The composition of the material is unknown to me. Where brass,CI and most aluminium alloys machine like a charm, this material is on the other side of the scale. It is a very tough material that is horrible to machine. Using a carbide insert for steel, gives curly chips/strings of about an inch long. However this leaves a horrible surface finish, almost like 30 grid sand paper. Each time a chip breaks of the surface, it leaves a small sharp burr. Using a carbide insert for aluminium (much charper) results in a completely worn out insert after a single pass.

In my search for a solution I found that the only thing that leaves a decent surface finish and does not eat the tool is using very low RPM i.e. surface feet per minute, a small feed rate and a very sharp HSS tool (below marked in red).

Drawback of this is that the chip does not break at all. You will get a continious long chip of several meters long that will produce a "birds nest" of about a food in diameter per pass. So frequently stopping the lathe and removing the swarf is the only thing you can do. This swarf is so tough that you have to cut it using a wire cutter. You can not tear them by hand without getting cut.

Finally I use a piece of sand paper to smooth out the surface roughness which is still rather high compared to nicely machining material like brass, CI and most aluminium alloys.

Next time I will try to cut them on my CNC lathe with and intermitting feed rate causing the chip to break by stopping the feed every few seconds. Payback for sure will be a more coarse surface finish as each time the chip breaks, it leaves a sharp burr. Just not sure if the tool will survive the intermitting cut as it will engage the material repeatedly.

View attachment 144031

Oewww. I thot the things were some kind of cast iron. Well, I'll find out how bad it is when I get tuit. But for now, thanx immensely for the info. I got mine at a scrap yard and they have them all the time. I can get incredible metals here because they have a lot of metal fabrication going on here. They make Genies here, and their scrap costs extra, still it is very high qual and cheap in comparison to having to buy it new. I saw, one time, a complete, un-opened block of 2" thick pieces probably 5feet by 9 or 10 feet. It must have weighed many tons. it was about 5 feet tall --not pile, they were bound together and all in the scrap yard. Can't imagine why they were there. It was worth a fortune in scrap, but what would it have cost new?

BTW, did you cut it with a band saw?

 

[xander janssen]

It was cut to length +4 mm (1/6") surplus by the supplier by bandsaw but it is also easily cut manually with a hacksaw, using a fresh sharp blade.

I do not own any power saw, so have to cut everything by hand. Looking forward to cut the 6 discs for the cooling jackets and cylinder heads out of 50mm (2") solid brass round stock.

 

[Richard Hed]

It was cut to length +4 mm (1/6") surplus by the supplier by bandsaw but it is also easily cut manually with a hacksaw, using a fresh sharp blade.

I do not own any power saw, so have to cut everything by hand. Looking forward to cut the 6 discs for the cooling jackets and cylinder heads out of 50mm (2") solid brass round stock.

That's very peculiar that it would cut easily with a band saw (or hack saw) but be so difficult to machine.

 

[xander janssen]

Xander,

Your cylinder liners look well done.

I look forward to seeing how your cylinder liner/cooling jacket assemblies will be attached to the crank housing.

Chuck

The cylinder will stand on the crank housing with a small ridge and above that ridge, there will be a octagonal ring (cut in two pieces) that will hold the cylinder down onto the crank housing.

A thought of pressing this octagonal ring onto the cylinder, but that would mean that I can never remove the cooling jacket in case the o-ring starts leaking or in case of other mishaps. I'm not confident enough that this cooling design will work as this is my first water cooled engine and because I'm highly constrained in the design by the fact that this engine should look like the real one as good as possible.

 

[kuhncw]

Xander,

Thank you for explaining the cylinder to crank housing attachment. Your cylinder material sounds difficult, but it certainly has a good bore surface.

I've always made cylinders from cast iron bar as it is easy to machine. Currently I'm building a single cylinder engine and using drawn over mandrel steel tubing for the cylinder. This is the first time I've tried steel tubing to eliminate some machining.

You mentioned concern about adequate cooling. Looking at your cylinder and head section view, I think you will have no problem. Your design looks very similar to the coolant passages in my two cylinder Titan engine (Doug Kelley's design). The Titan is a 400-500 rpm engine with 0.900 inch bore and 1.40 inch stroke. A small gear pump circulates coolant through the engine to a 2.5 inch diameter copper pipe cooling tank about 7 inches tall. Thirty minutes of running raises the coolant to 150F (65C). The pistons and cylinders are both cast iron so mismatched expansion is not a concern.

Good luck with your design and build. I'll be following.

Regards,

Chuck

 

[Richard Hed]

I took the time to look at what cylinders are made from. Turns out, they are made from many different things. Here is a page that has some:

https://blog.rangercaradoc.com/the-best-materials-for-manufacturing-hydraulic-cylinders-and-pistons

 

[xander janssen]

Found out that my cylinders are made from ST52, a easy to machine type of steel . Had a chat with a lady that knows a lot about machining and it turns out that I was doing the wrong thing, especially when using the carbide inserts. This tube has a hard layer and if you start with a gentle shallow cut, it ruins the tip of the insert, giving problems for the following cuts. With her information I sticked to HSS, stoned the cutting edge and now it is machining very well. Although still very long swarf, but with a proper chip breaker ground to the tool that should also be oke. For the final cuts I sticked to intermitting feed on my manual lathe instead of regrinding the toolbit.

 

[Richard Hed]

Found out that my cylinders are made from ST52, a easy to machine type of steel . Had a chat with a lady that knows a lot about machining and it turns out that I was doing the wrong thing, especially when using the carbide inserts. This tube has a hard layer and if you start with a gentle shallow cut, it ruins the tip of the insert, giving problems for the following cuts. With her information I sticked to HSS, stoned the cutting edge and now it is machining very well. Although still very long swarf, but with a proper chip breaker ground to the tool that should also be oke. For the final cuts I sticked to intermitting feed on my manual lathe instead of regrinding the toolbit.

View attachment 144110

Good to hear. And that is hydraulic cylinders.

 

[josodl1953]

Hallo Xander,
If you operate the engine as an petrol engine you will have to lower the compression( which means enlarging the combustion chamber)
Do you achieve this by shortening the piston or the conrod?

Groeten uit Rotterdam,
Jos

 

[xander janssen]

Hallo Xander,
If you operate the engine as an petrol engine you will have to lower the compression( which means enlarging the combustion chamber)
Do you achieve this by shortening the piston or the conrod?

Groeten uit Rotterdam,
Jos

By shortening the top of the piston by about 10 mm. This will bring the piston pin to about half height of the piston i.e. the piston will be more symmetrical while the original one is unsymmerical.

 

[xander janssen]

Cutted 4 discs out of 50mm (2") brass stock by hand to serve as raw material for the top and bottom of the cooling sleeve. The two tops are finished on the manual lathe, apart from the decorative outside. This will be done on the CNC lathe.

Next are the bottom sections and the two tubes. Once every thing slide fits together, parts will be soft soldered to form the cooling sleeve. The cylinder liners will remain a tight slide fit to allow disassembly. If ever needed in future.

 

[xander janssen]

Starts looking like the original.

 

[kuhncw]

Nice work, Xander.

 

[xander janssen]

Further building the design with the critical parts and dimensions and checking if the head can be fitted into the 3-jaw chuck (10mm black rectangles). First cilinder cooling jacket ready to be soldered.

 

[minh-thanh]

Just a thought,
Design it as a diesel engine, but now it will use gasoline and ignition. At some point you get more ....and change to diesel, maybe just change the crankshaft. ?

 

[xander janssen]

Went on board the Odilo (built in 1927) today to determine some last dimensions of the 2VD5. Very warmly spoken by Eddy who even started the engine for me. What an engine, at idle speed you just feel the boat sway around the longitudinal axis due to the individual power strokes.

Now I have all the dimensions needed to build the engine in 1:9.2 scale, including pictures of all the details that make it a "de Industrie". The first cylinder bushing and cooling jacket looks exactly like the original.
While enjoying tea, served in the right mugs , gave some explanation about how a working scale model of an engine is created from photos and drawings via a 3 D model.

 

[xander janssen]

Start working on the flywheel by cutting off the casting runners. Next is to mount and center it on the face plate. This 120 mm x 45 mm (5" x 1 3/4") piece of cast iron is the biggest I had ever on my small lathe.

Also made some brass type plate by transferring a laser printed graphic onto copper plate by "acrylic gel medium" method. The smallest, just readable will go on cylinder nr 1. The medium or biggest will go on the wooden display base.

 

[Nikhil Bhale]

The middle pushrod operates a "camshaft operated air valve" in the picture below. This image is a cross section right through the middle pushrod.

Before the engine is started, it is cranked in a certain position in which this valve is opened by the camshaft and the piston just past TDC.

To start the engine, the operator opens a valve (not in this image) in the high pressure (200 bar = 2900 PSI) supply line. By that, the air (red route) rushes in, past the camshaft operated air valve that is open and then into the cylinder by pushing open the spring operated "start valve".

This air forces the piston down, and the "camshaft operated air valve" is closed just before BDC.

Modern marine engines use same principle for starting. Only thing that has changed is the starting air valve is opened by pilot air rather than a cam shaft. There is no need to crank the engine to some particular position for starting and the starting air valve remains close during normal operation.
The danger of starting air valve leaking and hot exhaust gases coming to air manifold are still present though. We wrap thermal tape on air pipes, which changes colour based on temperature to keep an eye on air manifold.
Now we are require to have air all the time in tanks enough for 6 starting of non reversible and 12 starting of reversible engine. Air is stored at 30 bars.

Regards
Nikhil

 

[xander janssen]

Type plates done

 

[xander janssen]

Very nice casting. Only needed to remove 0.6 mm (0.02") off the thickness and 2.5 mm (0.1") of the diameter to clean it up. There are only 3 hard inclusions in the side face, for the rest, very homogenious cast iron.

Next are the cranking holes and polishing.