mcdavidr--Strange question, but did it run?
my attempt at Rupnows imperialized ridders flame eater
- Thread starter werowance
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Sorry don't know much about posting to forums
Sorry don't know much about posting to forums
Cogsy
Well-Known Member
Most people find it easier to upload videos to YouTube and then just paste a link in your post. Normally the video will then show up within your post itself. Entirely up to you though.
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Nice mcdavidr, I really need to get back in the shop, all I have accomplished this week is cut a pice of round stock and put it in the 3 jaw chuck. nothing else..... but my garden is about caught back up and I almost finished mowing last night so hopefully it wont be much longer, I'm on the last few bits now....
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today I have some encouraging news. it ran....
if I had to describe it, it was like an EKG heart read out. almost flat lined after I spun the fly wheel ...then I moved the flame a bit and it started picking up speed to a decent speed. unfortunately in my haste to grab my phone to video it, (I use my truck tailgate as a work bench...who doesn't lol) I caught the corner of the tailgate with my hip and bounced it which almost knocked the burner completely off the base and the engine stoped. ripped my pants, scraped my hide..... I could never get it going again.
now some background on what ive been doing the past few days. I have the cast iron bar for the valve and piston but on ebay I found graphite stir rod in broken condition. the was only a couple of dollars so I said why not try it first. this stuff is pourus as all get out. it looks like its cast with lots of air holes in it. but it machines very easily. so easily that I actually under cut just a bit so when I lapped it in, it didn't even remove all the machine marks on it. it did smoothe them down but I think its too undersized. but hey, I can make lots more with this rod and quickly to. so I will try graphite again before I switch to cast iron. you know use the soft stuff for trial and error first so I don't spend so much time machining and lapping in.
the hardest part so far has been the little link that connects the rod to the piston. it took 7 tries and even on that it still isn't perfect. for some reason my best tap and die kit would never form threads on the piece. it would just roll up the steel. I switched to a cheap harbor freight kit and it cut with no issues. glad that parts over with.
here are some pics cast iron bar next to broken graphite rod
and then a pic of the pourus graphite, then a pic of cross drilling that stuborn rod conector.
if I had to describe it, it was like an EKG heart read out. almost flat lined after I spun the fly wheel ...then I moved the flame a bit and it started picking up speed to a decent speed. unfortunately in my haste to grab my phone to video it, (I use my truck tailgate as a work bench...who doesn't lol) I caught the corner of the tailgate with my hip and bounced it which almost knocked the burner completely off the base and the engine stoped. ripped my pants, scraped my hide..... I could never get it going again.
now some background on what ive been doing the past few days. I have the cast iron bar for the valve and piston but on ebay I found graphite stir rod in broken condition. the was only a couple of dollars so I said why not try it first. this stuff is pourus as all get out. it looks like its cast with lots of air holes in it. but it machines very easily. so easily that I actually under cut just a bit so when I lapped it in, it didn't even remove all the machine marks on it. it did smoothe them down but I think its too undersized. but hey, I can make lots more with this rod and quickly to. so I will try graphite again before I switch to cast iron. you know use the soft stuff for trial and error first so I don't spend so much time machining and lapping in.
the hardest part so far has been the little link that connects the rod to the piston. it took 7 tries and even on that it still isn't perfect. for some reason my best tap and die kit would never form threads on the piece. it would just roll up the steel. I switched to a cheap harbor freight kit and it cut with no issues. glad that parts over with.
here are some pics cast iron bar next to broken graphite rod
and then a pic of the pourus graphite, then a pic of cross drilling that stuborn rod conector.
Congratulations on getting it running!
Mine is a little finicky to get started, the flame has to be in just the right place and it seems like it has to warm up a bit. Once it gets to the right temp itstarts easily. Your are right about making the piston pivot, a real pain. I made mine out of brass. If you need more graphite try http://beckergraphite.com/. Quality product and reasonably priced.
Mine is a little finicky to get started, the flame has to be in just the right place and it seems like it has to warm up a bit. Once it gets to the right temp itstarts easily. Your are right about making the piston pivot, a real pain. I made mine out of brass. If you need more graphite try http://beckergraphite.com/. Quality product and reasonably priced.
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I was warned against graphite, but I just wanted to see what it machined like, this engine is also my first bronze machining as well. but pretty sure this graphite stir rod is no where near "machinable grade" graphite. so after I use up the last of this stir rod if it still wont go ill switch over to the iron. I just don't want to wear out my cylinder lapping in iron before I had the chance to try out the graphite and see what it was like.
Werowance--Congratulations on your successful run.---Brian
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got to mess around with it last night for about 15 mins or so and did some tests on the piston and valve, they are definitely to loose, if I disconnect the push rod for the valve and hold the valve just closed over the intake I can hear the swoosh noise of air rapidly by passing both the piston and valve. I also get very little vacume affect when the piston is doing intake stroke while holding the valve in closed position. which is what I figured when I cut to far.
well, lets hope either I get a lot of yard and garden work done really quick, or it rains and rains and rains so I have to spend time in the garage
all this work is getting in the way of my fun lol.
well, lets hope either I get a lot of yard and garden work done really quick, or it rains and rains and rains so I have to spend time in the garage
all this work is getting in the way of my fun lol.
Cogsy
Well-Known Member
That stirring rod is horrendously porous, as you pointed out. The one I bought off ebay had no evident porosity at all and machined beautifully. It looks like I was just lucky - or maybe that's why the one you got was snapped in the first place - maybe it was a 'second' or part of a dodgy batch.
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probably, the other end appears to be a little more solid, with any luck I will get time this weekend to try and see. and hey, worse case I do have the cast iron.
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ok,help please....
1. the piston at top dead center, the top of it falls right about dead center of the intake slot on the cylinder , can I get a photo of someones intake slot with piston at top dead center?
2. I originally cut the threads to short for the piston rod connector as well as the valve conector. thus there is no in between to prevent the valve from sucking shut to soon and creating a vapor lock to soon. I remade just the valve conector with threads to length but not the piston conector and with that the valve cannot completely close by the adjuster that hits the skirt of the piston to pull the valve shut. if I move the adjuster enough to make that happen then I don't have enough travel on the valve push rod.
if I use the connectors that are cut flush with the tops of the pison and valve then I do get extended spin time and it tries to run. I have tried 2 sets of graphite and 1 set of grey cast iron piston and valves.
so if I can see where the piston should be at top dead center and maybe some close ups of the piston and valves with the connecting pins in them it might help.
1. the piston at top dead center, the top of it falls right about dead center of the intake slot on the cylinder , can I get a photo of someones intake slot with piston at top dead center?
2. I originally cut the threads to short for the piston rod connector as well as the valve conector. thus there is no in between to prevent the valve from sucking shut to soon and creating a vapor lock to soon. I remade just the valve conector with threads to length but not the piston conector and with that the valve cannot completely close by the adjuster that hits the skirt of the piston to pull the valve shut. if I move the adjuster enough to make that happen then I don't have enough travel on the valve push rod.
if I use the connectors that are cut flush with the tops of the pison and valve then I do get extended spin time and it tries to run. I have tried 2 sets of graphite and 1 set of grey cast iron piston and valves.
so if I can see where the piston should be at top dead center and maybe some close ups of the piston and valves with the connecting pins in them it might help.
My piston is dead even with the bottom of the port. It is hard to show in the photo. With the piston is at TDC there is only about .020 between valve and piston. The pushrod pulls the valve to completely cover the port about 10 to 20 degs before BDC. If you push the valve closed while the piston is on the down stroke the engine sort of vacuum locks. Hope this helps.
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