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  • VPT--Bar stock as opposed to castings. The cast iron cylinder is made from a piece of cast iron round bar--thus--bar stock. As far as the crankcase vent is concerned--I started the engine with the vent open, and while the engine was running I put my finger over the vent and sealed it to see what would happen.---Nothing happened--except that the engine got quieter. It does blow and suck at the hole and you can hear the air rushing in and out as the piston travels up and down, but its not a lot of pressure involved. It wasn't blowing my finger off the vent hole. I am running needle roller bearings on the con rod at both ends and sealed ball bearings on one side of the crankshaft (the driving side) and oilite bronze bushings on the non-driven (follower side) of the crankshaft. The roller bearings are greased with a heavy duty grease. The crankcase is dry--there is no oil in it. The cams and tappets are external and are given a squirt of oil from my oilcan. Since I am running a Viton o-ring on the cylinder, I mix a 30:1 mix of Naptha gas and two cycle oil to keep the cylinder lubricated.
    Brian Rupnow
    Design engineer
    Barrie, Ontario, Canada

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    • Highly entertaining as usual, Brian.
      Thank you very much for the download.
      I owe you a beverage of your choice ;-)

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      • I made up gaskets for the intake and exhaust flanges (I had forgotten to make them) and after a bit of tuning this morning, I got out my spanking new digital tachometer. This gave me pause, because at first it wouldn't work. Then I tested the batteries that came with it from the factory, and two of them were stone dead. After replacing two of the batteries and warming the engine up, I found that its lowest consistent idle was at about 800 rpm. It would idle lower, but then it faltered and threatened to stall. On the high speed end, it topped out at a whopping 1950 rpm. This is really about what I expected from the cam I designed. This is more of an "industrial" engine that likes a steady speed without wide rpm range fluctuations. It is really happy at about 1200 rpm, and would run all day at that speed without faltering. The heavy flywheel gives a good steady run, with a slow throttle response due to its mass. This engine is almost the exact opposite of the Canadian Cub (Malcolm Stride's Jaguar engine wearing Canadian clothes). I went to separate camshafts so I could set the cam timing of exhaust and intake totally independent of each other.--You simply can not do that with a one piece camshaft. On the question of cooling fans---I wanted a fan with a pitch which would push air over the cooling fins, rather than pull it, when rotated clockwise. (All of my engines are set up to turn clockwise). Unfortunately, the only fan I could find in the correct size range was designed to rotate counter-clockwise, thus the curvature (dished shape) of the blades. However---That doesn't mean they won't blow in the opposite direction if rotated clockwise. They just won't blow as efficiently. I don't need a whole lot of airflow---just enough to keep a steady flow of air over the cooling fins, to move the heat away. As for writing a book---I have had two of my engines published in "The Home Shop Machinist" magazine. I may see about publishing this one, because it is a very unique engine and seems to run very well.---Brian
        Brian Rupnow
        Design engineer
        Barrie, Ontario, Canada

        Comment


        • The engine runs well, but the gears are---ahh----noisy. I knew that they would be. They mesh well, and operate very smoothly now that I have an hours running on the engine. However, experience with other engines I have built sort of forewarned me that the open gearing would make a fairly noticeable "whirring" noise as the machine ran. That is why I made provision for an enclosure to go around the gears. An enclosure will cut down the noise quite a bit, will act as a containment for grease around the gears, and will provide some measure of safety (although I doubt I would have stuck my fingers in there anyways.)
          Brian Rupnow
          Design engineer
          Barrie, Ontario, Canada

          Comment


          • -Fabrication of the timing gear enclosure went very quickly with no problems. I did have to split it to get it on, as I had indicated on the drawing. The only problem I ran into is that I don't have any bolts long enough to bolt things together. I had to order a minimum quantity of one hundred #5-40 socket head cap screws x 1 1/4" long to get the 6 I need. That will probably last me for the rest of my natural life!!!
            Brian Rupnow
            Design engineer
            Barrie, Ontario, Canada

            Comment


            • When Ringo sang the song "It don't come easy" I'm sure he must have been thinking about something like this fan shroud!!! The only tube/pipe I could find slightly larger than my 3" diameter fan was a piece of schedule #40 3" nominal diameter steel pipe. It has a 3 1/16" inside diameter. I don't like working with pipe in the lathe.--It's nasty stuff to hold if you don't have a bull nose live center for the tailstock (I don't) and it has a propensity for jumping out of a 3 jaw chuck and rocketing around the room. This forced me to take .002" deep very light cuts until I had things close to the outside diameter that I wanted to end up with. The wall is still a little thicker than I would have liked, but it was just getting too scary. I have had a slight change of plan----I was going to silver solder it to the fan support bracket but that would have given me no adjustability at all. I have come up with a rather novel solution for bolting it to the fan bracket instead, giving me a bit of wiggle room if it ends up interfering with the tips of the fan blade anywhere.

              Last edited by brian Rupnow; 10-21-2014, 02:10 PM.
              Brian Rupnow
              Design engineer
              Barrie, Ontario, Canada

              Comment


              • Brian, I know that you now have a lot of effort in this shroud, but next time, you might try one of the heavy truck service centers. I went chasing after some largish tube and tried the local muffler shop. They had nothing over about 2.5" and sent me to a truck centre. They had some serious size exhaust tube in both steel and stainless.
                Just a suggestion.
                Duffy, Gatineau, Quebec

                Comment


                • Thanks Duffy.--Strangely enough, when I was developing this design, I thought about a piece of exhaust tubing, but when it came time to build it, I had kind of forgotten about it.
                  Brian Rupnow
                  Design engineer
                  Barrie, Ontario, Canada

                  Comment


                  • Going boldly where no man has gone be----Well, you get the idea.--Fan shroud is coming together nicely. At the last minute I decided to make the small pieces silver soldered to the steel hoop from brass. My reasoning--If I have to slot the holes with an end mill to move things around for fan clearance, the brass cuts easier. As you can see in the picture, the soldering job called for a couple of strange little "fixtures" to ensure that everything ended up where I wanted it to be. Now to ensure that the steel hoop will be concentric and clear the tips of the fan blades, I wrapped the fan with masking tape until I had .030" thickness of masking tape. Slid the hoop over that (snug fit) and will mark thru the brass ferrules welded to the hoop with a transfer punch to locate the holes I will tap in the fan stand.
                    Brian Rupnow
                    Design engineer
                    Barrie, Ontario, Canada

                    Comment


                    • So, there we are!! Painted up pretty and done like dinner!! Nothing rubs nor scrubs, nor interferes, but a business card won't fit into the gap between the flywheel and the bottom of the fan shroud.--But it does clear. And that, my friends, was the very last part I had to build for this engine. I have to wait a couple of days for my long bolts to come in that hold the timing gear covers in place, but that's it. I will post one more video before I'm done, showing the engine running at its slowest and fastest speeds because someone has requested it, but other than that, I'm finished. This has been a long thread, as I knew it would become when I started it in July, but it's been fun and interesting. I encourage anyone out there who has at least a couple of i.c. engines "under their belt" to build this engine. ---Brian

                      Brian Rupnow
                      Design engineer
                      Barrie, Ontario, Canada

                      Comment


                      • Very nice Brian. Are you going to build something for this to power? What about an air compressor? Or a lawn mower!
                        Location: The Black Forest in Germany

                        How to become a millionaire: Start out with 10 million and take up machining as a hobby!

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                        • BlackForest--That is always a question for me. To build something to run which has only one rotating part, i.e ferris wheel, merry-go-round, air compressor, generator, lawn mower just isn't very exciting. I like the Slinky machine, because it's fun to watch (we all had a slinky when we were kids, right?) I really like the sawmill. The bubble machine is kind of fun, because even though it only has rotating parts, the bubbles are fun---my grandkids love it. The Jacobs ladder staircase is rather fascinating to watch, as the balls march up the stairway and roll down the return track. The nodding donkey oil-pump is nifty, because we have all seen the big full sized ones pumping away in fields beside the highway in southern USA. The big "steam donkey" winch with the twin steam cylinders is fun to watch working. I started to build a marble moving automated machine a year ago, but got such a negative response from one of the U.K. sites that I post on, that I just stopped working on it. I'm really not sure if I will build something for this engine to power or not.---Brian
                          Brian Rupnow
                          Design engineer
                          Barrie, Ontario, Canada

                          Comment


                          • Originally posted by brian Rupnow View Post
                            BlackForest--That is always a question for me. To build something to run which has only one rotating part, i.e ferris wheel, merry-go-round, air compressor, generator, lawn mower just isn't very exciting. I like the Slinky machine, because it's fun to watch (we all had a slinky when we were kids, right?) I really like the sawmill. The bubble machine is kind of fun, because even though it only has rotating parts, the bubbles are fun---my grandkids love it. The Jacobs ladder staircase is rather fascinating to watch, as the balls march up the stairway and roll down the return track. The nodding donkey oil-pump is nifty, because we have all seen the big full sized ones pumping away in fields beside the highway in southern USA. The big "steam donkey" winch with the twin steam cylinders is fun to watch working. I started to build a marble moving automated machine a year ago, but got such a negative response from one of the U.K. sites that I post on, that I just stopped working on it. I'm really not sure if I will build something for this engine to power or not.---Brian
                            If you want a lot of moving parts then build a sheep shearing machine for your engine to power the miniature hydraulic motor you will have to build.
                            Location: The Black Forest in Germany

                            How to become a millionaire: Start out with 10 million and take up machining as a hobby!

                            Comment


                            • Liar Liar--Pants on fire---I said I wasn't going to post anymore but---I have never really liked the base I made for this engine. Oh, it was a lot better than the long angles that I had first proposed, but somehow it never looked--uhh---industrial enough for me. so--Today being free time, and having a bit of 3/4" aluminum left over, I made a new base. I like it much better.

                              Brian Rupnow
                              Design engineer
                              Barrie, Ontario, Canada

                              Comment


                              • As Bugs Bunny would have said----That's all folks. Thanks for following.---Brian
                                https://www.youtube.com/watch?v=6mQe...ature=youtu.be
                                Brian Rupnow
                                Design engineer
                                Barrie, Ontario, Canada

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