With large diameter steel wire,I think you should make the diameter of the spring larger in the middle and only smaller at the two ends, when the diameter is larger, its tension will decrease.
Philip Duclos Fire Eater
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fcheslop
Well-Known Member
For burners I like to use copper pipe reducers as they are cheap and available
The original burner canbe adjusted by pivoting it around.The flame needs to be as close as possible but not touching the valve
The spring on my engine is as rough as a badgers backside but looks a lot finer wire than you have used I think it was wound from a guitar string
I found on my first few runs as it bedded in the timing needed retarding or else it rattled along the bench
I v attached a link just to show the fittings as I dont know what they are known as in youre neck of the woods
https://www.google.co.uk/aclk?sa=l&...hUKEwipoKKIlY7dAhWSLFAKHfGPDcwQ9aACCDo&adurl=
The original burner canbe adjusted by pivoting it around.The flame needs to be as close as possible but not touching the valve
The spring on my engine is as rough as a badgers backside but looks a lot finer wire than you have used I think it was wound from a guitar string
I found on my first few runs as it bedded in the timing needed retarding or else it rattled along the bench
I v attached a link just to show the fittings as I dont know what they are known as in youre neck of the woods
https://www.google.co.uk/aclk?sa=l&...hUKEwipoKKIlY7dAhWSLFAKHfGPDcwQ9aACCDo&adurl=
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Thanks. I was actually thinking of trying a string off one of my guitars. I'm due to change strings on a few of them. The third string be around the .015" that Duclos calls out. I just don't know if a wire guitar string is "music wire" or if it's too weak, too strong, too something.
For an alcohol lamp, I was thinking of buying one. Making one is almost in the realm of "why bother?" There's a handful of cheap options on eBay, like this one. It's a bit too tall, but there are lots of options.
fcheslop
Well-Known Member
Not sure if youve seen this but it maybe of some use
http://www.deansphotographica.com/machining/projects/springs/springs.html
http://www.deansphotographica.com/machining/projects/springs/springs.html
Yes, I've been there before. Good site. Thanks for the reminder.
fcheslop
Well-Known Member
Dean was / is a member although he has not posted for sometime
Good luck with the rest of the build
Good luck with the rest of the build
Still won't run.
I changed the spring over from the one on the bottom (wire too thick, spring too short) to one more like the one on the top, only a little longer.
Still not quite the way Duclos describes it, but this is my first experiment winding a spring on the lathe as Dean shows. Made from a guitar string (.013) and the one I used is better seen here:
It's 20 turns and Duclos said to make 32 turns. I need to work on that. Here's today's video. I preheated the cylinder with a butane torch for 30 seconds, then kept the new alcohol lamp where it's visible here.
Last week, there was some talk about changing the cam timing. I do see the compression in the cylinder blowing the flame aside for just a fraction of a second. You can see in the second picture that the piston is about as far in the cylinder as the crank allows it. The valve is all the way open and that spring pushing the cam roller onto the straight side of the cam. Can someone tell me if that's right? Which way should I move it?
Thanks.
I changed the spring over from the one on the bottom (wire too thick, spring too short) to one more like the one on the top, only a little longer.
Still not quite the way Duclos describes it, but this is my first experiment winding a spring on the lathe as Dean shows. Made from a guitar string (.013) and the one I used is better seen here:
It's 20 turns and Duclos said to make 32 turns. I need to work on that. Here's today's video. I preheated the cylinder with a butane torch for 30 seconds, then kept the new alcohol lamp where it's visible here.
Last week, there was some talk about changing the cam timing. I do see the compression in the cylinder blowing the flame aside for just a fraction of a second. You can see in the second picture that the piston is about as far in the cylinder as the crank allows it. The valve is all the way open and that spring pushing the cam roller onto the straight side of the cam. Can someone tell me if that's right? Which way should I move it?
Thanks.
Now ,
I think :
Did you check that the valve and the piston are airtight? In the video, I feel it does not seem to make a vacuum (- the flywheel turns back only when the spring is compressed, and it is not vacuum)
Like Cogsy said, "The thing I notice is your flame looks pretty yellow / orange in the video, what fuel are you using? I use ~ 95% alcohol and the flame has more blue in it, so is likely a bit hotter coal yours.
As for the timing, some air has been expelled from the port at the top of the stroke to get rid of exhaust gases so I would not be concerned about that. "
I think :
Did you check that the valve and the piston are airtight? In the video, I feel it does not seem to make a vacuum (- the flywheel turns back only when the spring is compressed, and it is not vacuum)
Like Cogsy said, "The thing I notice is your flame looks pretty yellow / orange in the video, what fuel are you using? I use ~ 95% alcohol and the flame has more blue in it, so is likely a bit hotter coal yours.
As for the timing, some air has been expelled from the port at the top of the stroke to get rid of exhaust gases so I would not be concerned about that. "
The alcohol I'm using is "Klean Strip denatured alcohol", and tab 5 on that page says, "Klean-Strip® Denatured Alcohol has between 40 – 50% ethanol and 50 – 55% methanol." It might be possible to get something better from the drug store, but it's what the hardware stores around here sell.
If I take the steel valve off and just put my thumb over the valve opening, I can feel the pressure while trying to pull the piston down the cylinder. The difference in force it takes to move the piston is noticeable. The piston was too tight when I first put the engine together and would bind in one spot along the cylinder, so I ran the engine with my electric drill for about a minute to loosen it up just little.
I'm not quite sure what I could do to test how tightly the valve seals. It doesn't seal as tightly as my thumb does, but I can feel air being ejected as the piston comes to the "top" of the cylinder.
Can help you understand more ...airtight
1 / No springs
Video :
2 / springs :
Video :
1 / No springs
Video :
2 / springs :
Video :
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Thanks, Minh!
Just so I'm sure I understand, in video 1, you disconnect the rod to the valve, and the seal is so tight the piston hardly moves. Right?
Just so I'm sure I understand, in video 1, you disconnect the rod to the valve, and the seal is so tight the piston hardly moves. Right?
fcheslop
Well-Known Member
Thats correct Bob and on the Duclos you should find it is the same
Also check the valve can swivel on the shim spring as it may come off the port if theres the slightest misalignment .Hence the D shaped cut in the valve and the D shape on the end of the shim bit.
With the port blanked when you pull the piston to bottom dead center it should snap back up the bore .
The flame you use looks very yellow I prefer to use shellac thinners that French polishers use not sure what its known as over youre neck of the woods
What are you using to lubricate the cylinder as these engines hate any oil
Also check the valve can swivel on the shim spring as it may come off the port if theres the slightest misalignment .Hence the D shaped cut in the valve and the D shape on the end of the shim bit.
With the port blanked when you pull the piston to bottom dead center it should snap back up the bore .
The flame you use looks very yellow I prefer to use shellac thinners that French polishers use not sure what its known as over youre neck of the woods
What are you using to lubricate the cylinder as these engines hate any oil
OK, I ran a test by disconnecting the push rod and flicking the wheel to see if it spun. Nope. The valve pulls shut.
Fcheslop - I though they were the same thing: denatured alcohol. Like I said a few posts ago, the manufacturer says about 50/50 ethanol and methanol (the poisonous stuff). This web page makes it sound like it should be good for thinning shellac.
What percentage ethanol should I look for? I have no idea what else is out there. I have a vague memory that pharmacists had really high percentage ethanol, the kind you drink, but could put in a little something to make it sellable (poisonous). I'll call around and see if anyone has more pure ethanol available.
Fcheslop - I though they were the same thing: denatured alcohol. Like I said a few posts ago, the manufacturer says about 50/50 ethanol and methanol (the poisonous stuff). This web page makes it sound like it should be good for thinning shellac.
What percentage ethanol should I look for? I have no idea what else is out there. I have a vague memory that pharmacists had really high percentage ethanol, the kind you drink, but could put in a little something to make it sellable (poisonous). I'll call around and see if anyone has more pure ethanol available.
fcheslop
Well-Known Member
This is whats I use when I cannot get the French Polishing thiners
https://darrantchemicals.co.uk/methylated-spirits
cheers Frazer
https://darrantchemicals.co.uk/methylated-spirits
cheers Frazer
Thanks! The difference is that web page says you methylated spirits are 10% methanol, 90% ethanol, instead of the 50/50 blend I have,
I just checked the four closest hardware chains and none of them carry any brand that gives any better than that.
However, it looks like Amazon carries 95% ethanol. Unless a call to the pharmacist shows I can get some from them, it will have to be Amazon.
I just checked the four closest hardware chains and none of them carry any brand that gives any better than that.
However, it looks like Amazon carries 95% ethanol. Unless a call to the pharmacist shows I can get some from them, it will have to be Amazon.
Could someone look at this picture and tell me if my cam is on the right way? The piston is at the top of its travel, just off Top Dead Center (as I understand it) with the large radius of the cam on the left side. I don't see how It could go any other way, but it could rotate with the top more to the right (closes valve sooner) or left (closes it later).
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I adjusted the slide valve for my engine (and I think it's the same as your engine )
"" 4. The adjustment of the flame-eater.
The correct movement pattern of the slide valve in the 360° cycle is crucial.
The valve must open the flame hole in the cylinder about 30° before the piston is in its position closest to the cylinder head. The reason for that is that the cooled flame gases also are compressed again to atmospheric pressure during the working stroke of the piston already before the piston has reached its end position. If the flame hole is opened too late a counter-acting pressure will occur in the cylinder; the engine slows down or even stops running than. This opening of the cylinder hole through the slide should preferably be as abrupt as possible. During this 30º the cooled gasses with atmospheric pressure escape trough the flame hole to the outside. The valve must close the flame hole again at the time the piston is arrived again at 20 to 30 º from the other end side of the cylinder.
The overlap of the valve over the flame hole at the time that this is closed needs to be close to zero. I even have the experience that the motors run better if there is a very small gap left with the thickness of a human hair! For this phenomenon I still don't have a good explanation yet, presumably this also has to do with the occurrence of any counter-acting pressure in the cylinder.
The pressure of the spring(s) that holds the slide valve against the cylinder surface need to be adjusted so that the valve moves very well parallel along the cylinder surface but with a minimum pressure to minimize frictions. In fact, the valve only needs to be kept in place because the partial vacuum in the cylinder will pull the valve to the cylinder surface making a good leak free contact.""
For more :
Link
http://ridders.nu/Webpaginas/pagina_ervaringen_tips_happers/ervaringenhappers_frameset.htm
And one more thing, in your video I feel like the engine does not move as smoothly as my video
"" 4. The adjustment of the flame-eater.
The correct movement pattern of the slide valve in the 360° cycle is crucial.
The valve must open the flame hole in the cylinder about 30° before the piston is in its position closest to the cylinder head. The reason for that is that the cooled flame gases also are compressed again to atmospheric pressure during the working stroke of the piston already before the piston has reached its end position. If the flame hole is opened too late a counter-acting pressure will occur in the cylinder; the engine slows down or even stops running than. This opening of the cylinder hole through the slide should preferably be as abrupt as possible. During this 30º the cooled gasses with atmospheric pressure escape trough the flame hole to the outside. The valve must close the flame hole again at the time the piston is arrived again at 20 to 30 º from the other end side of the cylinder.
The overlap of the valve over the flame hole at the time that this is closed needs to be close to zero. I even have the experience that the motors run better if there is a very small gap left with the thickness of a human hair! For this phenomenon I still don't have a good explanation yet, presumably this also has to do with the occurrence of any counter-acting pressure in the cylinder.
The pressure of the spring(s) that holds the slide valve against the cylinder surface need to be adjusted so that the valve moves very well parallel along the cylinder surface but with a minimum pressure to minimize frictions. In fact, the valve only needs to be kept in place because the partial vacuum in the cylinder will pull the valve to the cylinder surface making a good leak free contact.""
For more :
Link
http://ridders.nu/Webpaginas/pagina_ervaringen_tips_happers/ervaringenhappers_frameset.htm
And one more thing, in your video I feel like the engine does not move as smoothly as my video
Thanks again, Minh-Thanh. That piece from Jan Ridders gives me some numbers and things I can measure.
That's the part I feel least comfortable about, but the least sure about what to do.
I ordered a liter of 90% ethyl alcohol fuel from Amazon to be here Sunday. I made two more springs (different lengths) from the music wire that got here Wednesday. I'll try a few things while waiting for the fuel.
