Philip Duclos Fire Eater

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The crank arm.

CrankArmDone-Flipped.JPG


The brass press fit was a minor adventure, but not in bad way. I have a 4-jaw scrolling chuck for my Sherline micro lathe that I hardly ever used. Just the thing for holding a cube. So getting to justify tools you have is always a good thing.

Now the shocking part: this is the last part that requires machining. I'm having minor issues with the springs, and then drill the holes for the mounting plate, but it's getting to be time to build this up and try to get it to run.
 
Close, but no cigar. It's built but isn't spinning smoothly enough for me to think it's worth trying to get it to run off my alcohol lamp.

Assembled.JPG


The push rod for the sliding valve, visible in the middle with a spring around it, doesn't slide smoothly. It doesn't return to starting position like it should. The spring isn't wound from wire, the way Duclos wrote. I found a pen spring and abused by stretching it out. It has the same wire diameter.

At best, I just tweak the positions of some parts, maybe replace that spring with another that I have. At worst, the flywheel and it's mounting brackets might have to be moved slightly away from your point of view in this picture and that will require a bit of effort.

If anyone's reading this, wish me luck!
 
I know this question isn't part of your build thread CFLBob but I'll ask it anyway. Are you a B.C. Lions fan?
 
No joy. Can't get it run on its own. Sometimes it sounds like it wants to run but never goes more than about four piston strokes.

It spins fairly freely. I can feel resistance from compression and lower pressure in the cylinder.

Anyone have pointers of things to look for?
 
CFLBob!
I think you should reduce spring tension. I never use a pen spring for my flame eater
 
Thanks minh-thanh. I've been working primarily on that spring. I didn't make the spring as Duclos says. The first spring was taken from ball point pen. It was the right wire diameter, but too short, so I stretched it to fit. Second spring was too long, but a thicker wire. I cut that to length. Then cut it another turn shorter.

I guess I need to break down and buy some music wire to make the spring.
 
CFLBob !
In your video, I saw the engine move quite ok, but in about 24 seconds of video from the start, I saw the force of the springs too much.
 
Bob, I've not yet finished designing my flame eater so I'm not a qualified expert. But... I think your timing is off, or the duration, or lift, of the cam is wrong. You shouldn't have compression blowing the flame away (as in the video). These fickle engines can't stand compression working against them.
I'm struggling with my design for that very reason. I'm thinking of a check valve in the cylinder head.
 
Since I don't know who they are, I'm sure that means I'm not.
Just asking because with CFL at the start of your name reminds me of the Canadian Football League "CFL", the Lions are in the CFL.
 
I think the timing is key to make this run better. I would be inclined to have the valve shut a little before the bottom of the stroke that would add some vacumn to the power stroke and assist with that stroke.
 
Just asking because with CFL at the start of your name reminds me of the Canadian Football League "CFL", the Lions are in the CFL.

OK, I get it. CFL is the usual local abbreviation for Central Florida. I looked up the name BC Lions, and I'm about as far from British Columbia as you can get while still being on the same continent.
 
I think the timing is key to make this run better. I would be inclined to have the valve shut a little before the bottom of the stroke that would add some vacumn to the power stroke and assist with that stroke.

One of the features of the Duclos design is that the cam is adjustable, so I can vary the timing. I'm not sure which way to move it, but it's pretty much centered right now, as he recommends in the book. Post #78 shows the cam and the roller that rides on it and pushes the push rod.
 
Bear in mind I've only built the Jan Ridders flamelicker so I'm no expert. The thing I notice is your flame looks quite 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 than yours.

As for the timing, some air has to be expelled from the port at the top of the stroke to get rid of exhaust gases so I wouldn't be concerned about that. If you close the valve before BDC to get 'extra' vacuum, that power has to come from somewhere and you'll be robbing your engine of full power.

How much preheating did you before the video? If the cylinder is stainless it might take a minute or two to heat up enough for the engine to run. It's certainly making all the right noises. Check your fuel, preheat the cylinder and have another go maybe? Good luck!
 
I'm not an expert too :D
but in the video i saw the force of the springs too much. I think should reduce spring tension I think it will run. if not and with some check : temperature, adjust a little of time valve
 
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Set the cam full advanced. My engine runs retarded just to slow it down.
Set the valve so the leading edge only cover the port by 1/64
Is the valve seating Try turning the engine the wrong way and you should feel the suction it is fairly strong
The valve spring only needs to just keep the follower on the cam
Make a proper burner it may save you wobbling about like a one handed fan dancer
When starting make sure any condensation has burned off from the port face These engine some times need a wee bit of pre heating although the Duclos one doesnt suffer badly from the problem
If you need any pic from my old klunker just shout or a rough video
cheers
 
Bear in mind I've only built the Jan Ridders flamelicker so I'm no expert. The thing I notice is your flame looks quite 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 than yours.

As for the timing, some air has to be expelled from the port at the top of the stroke to get rid of exhaust gases so I wouldn't be concerned about that. If you close the valve before BDC to get 'extra' vacuum, that power has to come from somewhere and you'll be robbing your engine of full power.

How much preheating did you before the video? If the cylinder is stainless it might take a minute or two to heat up enough for the engine to run. It's certainly making all the right noises. Check your fuel, preheat the cylinder and have another go maybe? Good luck!

Fuel is from a can of Klean Strip denatured alcohol from the hardware store. The company website says about 50/50 ethanol and methanol mix. Should be about the same as yours. As for the color of the flame, possibly something dripped on the wick from another project a while ago. Or the wick burning itself. The wick is black, like it has been burning.

In that video, I didn't preheat the cylinder, but for most of the time I was working, I heated it 30 seconds or so in the flame, enough to get it too hot to touch. I had been messing with the engine for a long time and then had to break for an hour to recharge my camera's battery. Since I was just there to take the video, I just sat down to spin it. I mostly wanted folks to hear the sounds of the air compressing or escaping

The alcohol lamp was always supposed to be temporary. Virtually every video has a custom alcohol lamp and every video has the guy fooling with the placement to get it exactly in the right spot. Since the Duclos plans have a lamp made from a door knob that's permanently mounted, I thought I'd try something I already had and not mount make a mount for it until I found where it needs to go. The problem was I never pulled the lamp up to the cylinder until yesterday. That's when I saw it's much too big.

Looks like another week or so. I started cutting metal around the end of February, and didn't start this thread until May, another few weeks doesn't matter.

Meanwhile, I need to find some .015 spring wire to wind a spring. I think I mess with the spring before I mess with the timing. I said I started with a spring from around the house with .015 wire and stretched it out, then went to a bigger wire spring and cut it off. After the second time I cut it back it looks like this:
SpringGap.jpg


That gap isn't that big. Rough guess is 1/16". But it doesn't press the cam roller onto the cam. The slightly too long spring is less bad than this, but it needs to be replaced.

RollerGap.jpg


Somewhere in there, I make an alcohol lamp.
 

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