First Engine Build - A Flamelicker
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AussieJimG
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That's a beautiful machine Cogsy, a real credit to you.
And you say it runs! Wonderful! I built one (but not highly polished like yours) but never could get it to run so I swapped it for a busted model helicopter.
Later on I saw somewhere that you have to warm it up for some time before it will run. I thought it worked on the hot air and would be best in a cold cylinder. But apparently it uses the plasma from the flame. Did you need to warm it up before it would run?
At the time, the only graphite I could find was in the US and I think it cost about $150 for a 450mm length - about half due to US postage. I just had to hold my nose and jump. I have since used it (sparingly) on some other engines. I have also purchased some artists graphite crayons for stock but they are only about 10mm diameter. I am pleased to see that you found a cheaper source. Would you mind sharing the URL?
I note that you are using cotton wool for the wick. I went to one of the shops that sells slow combustion wood stoves and purchased some of the ceramic rope that they use to seal the doors. It doesn't burn when the fuel runs out.
After seeing your lovely model, I a tempted to try another one after I finish the current project. Thanks for sharing, I look forward to seeing the video.
And you say it runs! Wonderful! I built one (but not highly polished like yours) but never could get it to run so I swapped it for a busted model helicopter.
Later on I saw somewhere that you have to warm it up for some time before it will run. I thought it worked on the hot air and would be best in a cold cylinder. But apparently it uses the plasma from the flame. Did you need to warm it up before it would run?
At the time, the only graphite I could find was in the US and I think it cost about $150 for a 450mm length - about half due to US postage. I just had to hold my nose and jump. I have since used it (sparingly) on some other engines. I have also purchased some artists graphite crayons for stock but they are only about 10mm diameter. I am pleased to see that you found a cheaper source. Would you mind sharing the URL?
I note that you are using cotton wool for the wick. I went to one of the shops that sells slow combustion wood stoves and purchased some of the ceramic rope that they use to seal the doors. It doesn't burn when the fuel runs out.
After seeing your lovely model, I a tempted to try another one after I finish the current project. Thanks for sharing, I look forward to seeing the video.
Cogsy
Well-Known Member
Thanks for the comments everyone. I have now posted in the finished projects section, with a video as well.
AussieJimG - It's strange, I did get the engine to run before I polished it and it seemed to work best with a cool cylinder. I even chilled it in the freezer and it worked fine. Now that I've polished it (which might be a coincidence though as it has new piston and valve too), it will start and run for a little while, but you can see drops of moisture building up around and above the flame port and it will stop after a while. I then spin it for a little while (maybe 20-30 seconds) and as the heat builds up the moisture starts to disappear. When it's mostly gone, the engine starts to run fine again.
As for the graphite, I have found a site which sells it cheaply, but I don't know what their postage is like - http://www.beckergraphite.com/stock.html
Otherwise, I got mine from ebay for about $25 posted. Just search 'graphite stirring rod' and make sure you search international sellers. I just did and I see a 1"x24" for about $50 including postage to Australia. I'll be buying some more, it's great stuff to work with and I have an idea which will require lots more.
Thanks for the wick idea. I have read that soaking cotton in a salt water solution then drying it out works too. I plan on doing some experiments with various wicks as I think I'll be making more models that require burners.
If I can make one run then anyone can - good luck!
AussieJimG - It's strange, I did get the engine to run before I polished it and it seemed to work best with a cool cylinder. I even chilled it in the freezer and it worked fine. Now that I've polished it (which might be a coincidence though as it has new piston and valve too), it will start and run for a little while, but you can see drops of moisture building up around and above the flame port and it will stop after a while. I then spin it for a little while (maybe 20-30 seconds) and as the heat builds up the moisture starts to disappear. When it's mostly gone, the engine starts to run fine again.
As for the graphite, I have found a site which sells it cheaply, but I don't know what their postage is like - http://www.beckergraphite.com/stock.html
Otherwise, I got mine from ebay for about $25 posted. Just search 'graphite stirring rod' and make sure you search international sellers. I just did and I see a 1"x24" for about $50 including postage to Australia. I'll be buying some more, it's great stuff to work with and I have an idea which will require lots more.
Thanks for the wick idea. I have read that soaking cotton in a salt water solution then drying it out works too. I plan on doing some experiments with various wicks as I think I'll be making more models that require burners.
If I can make one run then anyone can - good luck!
d-m
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Really well done for a first try i'm impressed!!
On machining graphite I get it close to finished size then use news paper to bring it to fit then run it in nice to work with but vary messy.
On your soldering 2 things to remember flux is your friend and the solder always follow's the heat.
Again really nice flame licker I have plans for one my self some day I'll stop making tooling and build it.:bow:
Dave
On machining graphite I get it close to finished size then use news paper to bring it to fit then run it in nice to work with but vary messy.
On your soldering 2 things to remember flux is your friend and the solder always follow's the heat.
Again really nice flame licker I have plans for one my self some day I'll stop making tooling and build it.:bow:
Dave
Cogsy
Well-Known Member
I've been tinkering with this engine and I've made a bit of a discovery I thought I'd share.
I was making a few adjustments trying to get better performance and I managed to break the engine completely - it would not run, not even close :wall:. So I altered and remade the valve actuator rod and both end fittings, milled the holes in the flywheel, and experimented with changing the 'timing' a bit. Absolutely nothing worked and I was getting distraught.
I remade the piston and valve and still it wouldn't run, so I lapped the bore as I wasn't 100% happy that it was straight enough, and made yet another piston/valve set. It was now close to running but still wouldn't go.
After another frustrating week of fruitless tinkering, I decided to have 1 final attempt at it, and made a final piston/valve set. This is where it gets interesting.
Jan's instructions call for a stainless cylinder but I had used aluminium, and the plans call for a near frictionless fit of less than 0.03mm for the pistons in the bore. This final set I made are tight in the bore, really tight, like the engine is almost seized up, and it won't spin a full revolution, let alone the 5-8 seconds that Jan's troubleshooting guide suggests it should. But, after 30-45 seconds of flame, it spins a lot more freely, and begins 'kicking back'. Then 15-30 seconds later it will begin to run, even better than when it was first built.
I am assuming that there is a heap more thermal expansion of the Ali cylinder occurring than I thought there'd be, and I was losing seal on my pistons as it heated up. If anyone builds this engine with an Ali cylinder, I recommend trying a tighter fit on the pistons than the plans suggest.
I was making a few adjustments trying to get better performance and I managed to break the engine completely - it would not run, not even close :wall:. So I altered and remade the valve actuator rod and both end fittings, milled the holes in the flywheel, and experimented with changing the 'timing' a bit. Absolutely nothing worked and I was getting distraught.
I remade the piston and valve and still it wouldn't run, so I lapped the bore as I wasn't 100% happy that it was straight enough, and made yet another piston/valve set. It was now close to running but still wouldn't go.
After another frustrating week of fruitless tinkering, I decided to have 1 final attempt at it, and made a final piston/valve set. This is where it gets interesting.
Jan's instructions call for a stainless cylinder but I had used aluminium, and the plans call for a near frictionless fit of less than 0.03mm for the pistons in the bore. This final set I made are tight in the bore, really tight, like the engine is almost seized up, and it won't spin a full revolution, let alone the 5-8 seconds that Jan's troubleshooting guide suggests it should. But, after 30-45 seconds of flame, it spins a lot more freely, and begins 'kicking back'. Then 15-30 seconds later it will begin to run, even better than when it was first built.
I am assuming that there is a heap more thermal expansion of the Ali cylinder occurring than I thought there'd be, and I was losing seal on my pistons as it heated up. If anyone builds this engine with an Ali cylinder, I recommend trying a tighter fit on the pistons than the plans suggest.
Hi,
Congratulations onhaving a running engine as these engines are difficult ones to get going.
Jan's recommendation for a stainless steel cylinder is to have a none corrosive metal as the combination of water and other acids formed by combustion could do a lot of damage to the cylinder. Aluminium should be fine as far as the water is concerned. You are absolutley right about Aluminium expansion, I wonder what would happen if both cylinder and pistons were made from Aluminium? My engine has a Cast iron cylinder but it has never run reliably and I am thinking about a total rebuild ,maybe this time I use AlY. I believe that cast iron retains the heat better bt Aly is a betetr heat conductor.
Regards,
A.G
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