Nov. 2015

The October Meeting

There was some discussion about shows during the summer: Kasey Schuilenberg went to Blyth and took his models to display. Apparently it was a good show (as usual.) We put on a display at Hobbyfest and at the time I had no pictures. Nick Jonkman was there and took some, so I have included them later in this newsletter.

The simpler approach is to use parallel depth gears. He has been researching this and has now posted some calculations on our website (mentioned earlier.)

Rick Nickels talked about his trip to Vancouver and looking at the Gastown steam clock there. (I saw it on a visit some time ago but had forgotten about it.) The following photograph is from the web.

Gastown Steam Clock

Tony Koolen, Alex Herpers, Murray Bennell, Ed Spencer and Martin Beales went along to the meeting in Hamilton on September 20th. This was a get-together for the model steam locomotive enthusiasts.

Bruce Mannerow talked about the projects page on our website and has been taking photographs of members’ models to include (there is a link towards the end, please check it out under "Member’s Project.") He has also added a couple of items to the "Downloads" section, one is on calculations for ball turning, the other is on calculations for producing parallel depth bevel and miter gears A further addition to the website is a list of the books available in our library (looked after by Keith Orr.)

Our election/appointment of club officers also took place during the meeting. Bruce Mannerow was unanimously re-elected as president, the Treasurer and Secretary/Newsletter Editor remain in those positions.

Don Eastman attended as a prospective new member. I had been introduced to Don and his wife back in August by some mutual friends. I had heard about his extensive basement railroad layout and went around to see it. During our meeting, Don told us about his interests: Until now his main activity has been the "O" gauge railroad layout in his basement. However, he has now taken on a project for Charlie Fairbanks; modelling an oilfield jerker rod installation. He needs to make a belt drive system as part of this and is looking for some help.

Bruce went on to talk about his efforts to make some bevel gears for the elevating mechanism of his 18 pounder. He was unable to buy anything suitable and making true bevels gears needs specialized gear cutting equipment.

Tony’s Locomotive

Show and Tell

Tony Koolen brought along his look-alike diesel-electric locomotive which is actually a battery powered electric locomotive. He has been working on various parts for this and has bought a controller and a sound system to make it sound like a real diesel locomotive. He demonstrated it all working during the meeting. There are 2 x 12V batteries to give the 24V needed by the motors (that can be seen front and back.) At the back is the controller and sound generator, on top is the loud speaker that makes all the noise

As usual Mike Clark has been hard at it. He brought along the completed crankshaft and camshaft for his Mastiff. The cams have been made individually and then keyed on to the shaft. On the left is part of the jig used for machining the cams.

Free lance hit and miss engine

Kasey Schuilenberg brought an anvil and hammer mill that he has made from his own castings (note the cast-in initials.)

Anvil and hammer mill

Larry Walkers Boats

grinding operation is used to bring the mounting surfaces within the required tolerances.

They supply dies for a wide variety of applications such as wood pellets, cattle feed, chicken feed and even shrimp feed. Some of the statistics are very impressive (one company they supply to make 700 tons of chicken feed per day! Can you imagine how many chickens that would feed?)

Although most mills use the cylindrical die arrangement, some use a flat plate with axial holes. Click on the following to get some pictures of both pellet mill arrangements. We were asked not to take photographs during the visit because they want to preserve confidentiality about some details of their manufacturing operation. (For the same reason it would be unfair to describe their operation in greater detail.)

https://www.google.ca/search?q=Pellet+mills&biw=1368&bih=667&tbm=isch&tbo=u&source=

univ&sa=X&ved=

0CEgQsARqFQoTCN7gnfvC4cgCFcVdHgodQKAD9Q&dpr=

Tee shirts

Visit to Dorssers Inc.

This is the company that Tony Koolen talked about last season. They are located in Blenheim and make dies for pellet mills. Tony arranged a visit there and eight of us went along to look at their operation.

After a further operation to chamfer the lead-ins to the die holes (from the inside) the die is heat treated to provide the necessary degree of hardness. Some distortion occurs during this process so a final

(Unfortunately some further confusion will arise later because as hot bulb engines morphed into semi-diesels, some engines used what amounted to a hot tube to ignite the oil spray.)

Continuing with the hot bulb story; a wide range of developments took place over the years. In fact because there were so many companies producing the engines in many different countries, it is difficult to

pull together anything like a comprehensive story of what was done. Looking at the Hornsby-Akroyd developments, the sectional arrangement one normally sees (as shown in the last installment) is that of the engines produced prior to ~1895. With these, most of the bulb was heated but this also tended to overheat under full load conditions, resulting in premature ignition and detonation of the oil vapour/air mixture. To avoid severe detonation, the compression ratio was limited to ~3 : 1 (around 40psig compression pressure.) The situation was improved by reducing the size of the heated portion of the bulb. This was done by water jacketing the end closest to the cylinder. This smaller hot area allowed the engines to operate with a slightly higher compression ratio (~5:1 - 6:1) and this resulted in some improvement in efficiency. The 1902 De La Vergne engine at Coolspring (again shown earlier) is of this type. The later type also had the heated part as a separate bolted-on component. This helped avoid cracking problems that arose from of the thermally induced stresses in the one piece design with one end hot and the other end cold because of the cylinder cooling.

This is the arrangement:

played in the development of the engines after Hornsby took on the manufacture. Apparently he moved to Perth, Australia in 1899, so presumably did not contribute to the later improvements.

A similar development took place with De La Vergne. Their DH type, which appeared ~1915, just had a hot plate section for vaporization/ignition of the oil and a compression pressure of ~300 psi which corresponds to a ratio of ~9:1. As is often the case, they got into the business by taking out a licence, then went their own way after gaining sufficient experience themselves. This is termed a "moderate" pressure engine and according to one source it would start from cold using a smouldering fuse inserted into the combustion chamber. However, other sources indicate that heating the plate with a blowlamp was the more normal approach. Once running, the hot part of the combustion chamber would remain at a high enough temperature to sustain ignition.

Although they were more efficient than the lower pressure types (maybe comparable with the diesel engines of their time) they also had to be built more heavily built than the earlier hot bulb engines.

Overall, the course of development was to go to higher compression ratios, a smaller heated surface and later oil injection so that they started to resemble diesel engines. It is convenient to regard the early Hornsby-Akroyd arrangement as type 1, the later type with part of the combustion chamber water jacketed as type 2 and engines such as the De La Vergne type DH with a much higher compression ratio as type 3. These did not have a high enough compression ratio to ignite the fuel by compression heat alone but were getting close to that point. Therefore, although the terms hot bulb and semi diesel tend to be used interchangeably, in reality "hot bulb" relates more to the earlier engines and "semi diesel" to the later ones.

Although this was a general trend, the progression was not uniform across the board. For example, looking at the Lanz Bulldog tractors; until 1952 they were really like a type 2 with a compression ratio in the 6:1 - 7:1 range and part of the combustion chamber cooled. There was then an interim version with a ~10:1 compression ratio (a semi diesel) before

Later on, electrically powered glow plugs were used to provide the hot surface to get the engine started, either dispensing with the blowlamp altogether or acting as an optional means of providing a hot surface. In this and the hot tube (firing tube) case, once the engine started, combustion sometimes heated up a larger surface that provided the source of ignition in normal operation (e.g. 1 in the diagram below.)

Later on (~1912) they went even further and used a much smaller heated bulb.

A later development was the use of compressed air to atomize the kerosene so that no pre-heating of the burner was required. Where compressed air was used for starting it was also available for this purpose and must have made things much easier on multi-cylinder engines. This is an engine made by Gardner.

The conventional hot bulb had a significant weight of metal to heat up and this took some time. One way of improving on this was to use a mini hot bulb, essentially a hot tube. This could be heated more quickly and still be large enough

November 9th

December 14th