Old Koreelah Posted July 28, 2013 Share Posted July 28, 2013 You probably feel like an expectant father. Hope all goes well! 1 Link to comment Share on other sites More sharing options...
AVOCET Posted July 28, 2013 Share Posted July 28, 2013 You probably feel like an expectant father. Hope all goes well! Who's the Mother ? Link to comment Share on other sites More sharing options...
Old Koreelah Posted July 28, 2013 Share Posted July 28, 2013 Who's the Mother ? The foundry. 1 3 Link to comment Share on other sites More sharing options...
Jabiru Phil Posted July 28, 2013 Share Posted July 28, 2013 The foundry. What caste? 1 Link to comment Share on other sites More sharing options...
Old Koreelah Posted July 28, 2013 Share Posted July 28, 2013 What caste? Untouchable- its still too hot! Link to comment Share on other sites More sharing options...
paulh Posted July 29, 2013 Share Posted July 29, 2013 And after you make a raging success of the 94 hp engine how about a 50hp or so four stroke engine to compete with the two strokes. 1 Link to comment Share on other sites More sharing options...
bexrbetter Posted July 29, 2013 Author Share Posted July 29, 2013 What caste? Very clever! how about an engine to compete with the two strokes. I have a little secret experiment that is undeway actually, it's about halfway developed. My good friend Mal Beare's "6 Stroke" engine has a place in aero as well because the secodary crankshaft running at half speed can direct drive the prop and when Mal gets his current troubles sorted out I might be chatting to him about it. And then there's the 2.4 litre lightweight V8 (smooth 180hp very cheap) we got on the drawing board along with the 1.6 flat 6 - not short of backups! But I am a one step at a time guy and I just had a phone call while writing this that I need to be at the casting works this Thursday or Friday - I will get pictures. 1 Link to comment Share on other sites More sharing options...
geoffreywh Posted July 30, 2013 Share Posted July 30, 2013 QUOTE "how about a 50hp or so four stroke engine to compete with the two strokes." Please excuse my ignorance, But I thought that particular size was very well served. I can think of 4 There's the HKS and the American flat twin, whose name escapes me , then the NZ paralel twin, and of course great plains jobbies....What did I miss?.... Link to comment Share on other sites More sharing options...
paulh Posted July 31, 2013 Share Posted July 31, 2013 Well it seems that none of the 4 strokes are popular by comparison to the two strokes - HKS seems to have a good reputation but perhaps a bit expensive, the American V twin from Valley Engineering a converted industrial engine has gone quiet, the NZ Aerotwin ownership back to the Kiwi designer but seems to also have gone a bit quiet, cash flow may be an issue (Quicksilver Aus testing one, info on web site), the American Thunder Aviation in line twin gone quiet (gone broke?), Half VW - not many seem keen on an old engine case cut in half (not my idea of how to build an aero engine) full VW plenty of these GPA, Casler, Sonex, Revmaster etc but most more than 50hp and perhaps not a real direct type replacement for a two cylinder two stroke. Weight probably an issue with VW types. Link to comment Share on other sites More sharing options...
facthunter Posted July 31, 2013 Share Posted July 31, 2013 Reasonable summary paulh. In some ways we have not advanced much. The smaller engines are only for single seaters really and they are not that common today. The 582 new is still probably hard to beat as it is light and comes with varying redrive ratios, and has the right power. A flat twin could be made cheaply. It makes a better noise than a two stroke. OK if you don't go for too much power and revs. I've often thought of using two cylinders off a Continental 0-200 or something similar as that is the most expensive part to make. Nev Link to comment Share on other sites More sharing options...
bexrbetter Posted July 31, 2013 Author Share Posted July 31, 2013 I've often thought of using two cylinders off a Continental 0-200 or something similar as that is the most expensive part to make. Nev There is one out there already if you look for it (no, I don't know where but have seen it). Link to comment Share on other sites More sharing options...
facthunter Posted July 31, 2013 Share Posted July 31, 2013 thanks Bex. Nev Link to comment Share on other sites More sharing options...
paulh Posted July 31, 2013 Share Posted July 31, 2013 A smaller lowered powered engine would be a good match with Garry Morgans single seat touring motor glider based on his Super Diamond or his other self launch glider ideas. I recall him saying on a post on another thread that about 50hp would be about right. Link to comment Share on other sites More sharing options...
facthunter Posted July 31, 2013 Share Posted July 31, 2013 I have had some experience with the HKS. The motor is running a fairly high compression but the newer ones may be different. A four stroke has a much more manageable exhaust system than a two stroke. I would say it is slightly less power than a 582,. but not much. Nev Link to comment Share on other sites More sharing options...
geoffreywh Posted July 31, 2013 Share Posted July 31, 2013 The half veedub from Leonard Mullholland does not use a cut case, has 90mm barrels, twin mikunis and looks quite good......................I saw info on a 1/3 ! corvair......But hardly a certified aeromotor...If, as you say, the others are in the doldrums .I see your point.......................An update, The Valley engineering " Big Twin " has had some revamps and is now the "Big Bad Twin" Last news I found was late 2012. A little search shows a nice 40hp engine ...............savoiacars.dot.com... comes from citroen.... Link to comment Share on other sites More sharing options...
bexrbetter Posted July 31, 2013 Author Share Posted July 31, 2013 An update, The Valley engineering " Big Twin " has had some revamps and is now the "Big Bad Twin" You will find the 'Backyard Flyer' plane/mob has some link to the Valley engine. Link to comment Share on other sites More sharing options...
bexrbetter Posted August 7, 2013 Author Share Posted August 7, 2013 Anyway, the mold company are getting along nicely with my finalised crankshaft housing design. Look familiar .... Still a long way to go but off to a good start These are sample batch of raw castings straight out of the molds for me to measure and inspect and change where required .... 4 Link to comment Share on other sites More sharing options...
Old Koreelah Posted August 7, 2013 Share Posted August 7, 2013 Wow, first baby pix! A very exciting time for the new dad... 1 Link to comment Share on other sites More sharing options...
bexrbetter Posted August 7, 2013 Author Share Posted August 7, 2013 Wow, first baby pix! A very exciting time for the new dad... Lets hope there's not too many shitey nappies and broken sleep ... Here I just sat the oil pump onto the crank housing along with the alternator bracket - the height of the crank housing was determined by the oil pump as you can see (about 5mm will be machined from the height). As I have mentioned previously, the whole idea is to use mass production items where possible and the oil pump here is an example.... 4 Link to comment Share on other sites More sharing options...
Old Koreelah Posted August 7, 2013 Share Posted August 7, 2013 As so many teenage parents discover, there is a lot more to parenthood than they expected... Link to comment Share on other sites More sharing options...
bexrbetter Posted August 11, 2013 Author Share Posted August 11, 2013 I wanted to size a few things up today but alas my crankshaft won't fit into the unmachined housings, will have to wait until I receive a few of the machined ones around the 20th. You can see the aproximate stick through of the con rod ... 2 Link to comment Share on other sites More sharing options...
Old Koreelah Posted August 11, 2013 Share Posted August 11, 2013 ... A four cylinder motor has a situation twice each revolution where all pistons are stationary. This reduces their flywheel effect at those points to zero. A six cylinder motor never has more than two (out of six not four out of four) stopped, there fore much less need for a flywheel. The prop is most of the flywheel and there is less load imposed upon it... Nev From the look of your cranks, your engine will be very smooth and not need a flywheel. Link to comment Share on other sites More sharing options...
geoffreywh Posted August 13, 2013 Share Posted August 13, 2013 good looking forged? crank....nice big journals... how you gonna arrange the mains bolts? right through? Link to comment Share on other sites More sharing options...
turboplanner Posted August 13, 2013 Share Posted August 13, 2013 Congratulations on your progress of turning dream into reality. No doubt there will be more hurdles to be solved, but this already is a good success! Link to comment Share on other sites More sharing options...
bexrbetter Posted August 13, 2013 Author Share Posted August 13, 2013 forged crank....nice big journals.. Good eye and you're not kidding, 800cc triple yet uses 50mm mains! That also translates into decent overlap of the BE journals and it's quite short adds up to make a hell of a stiff and robust crank for the job. the mains bolts? right through? Yuh, if you look at the castings carefully you can see the bosses for them. Those bosses are the biggest reason for the new castings, was too difficult just to cut an existing engine down although I looked far and wide for a suitable one but anyway, has worked out well. Not bolts of course, studs. Here you see my experimental cut up and drilled through housing that influenced the new one's design, especially stud bosses arrowed .. Studs will be part of the center housing and the crank housings will slide on, then the main caps. Messy assembly work for me but not complicated and certainly easier than a Subaru for example and no harder than a VW Congratulations....... Thank you, appreciated.. 1 Link to comment Share on other sites More sharing options...
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