Coming along nicely

[NickG]

Looking good, I quite like the base - it's different.

Jan has some trouble shooting tips and guidelines on his website about how free running it should be with and without piston / valve assembly on the other flame licker that I made but this has an even lower power output so reducing friction is more critical. Still, might give you some pointers, look at the video on top right too.

http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_happer_inw_schuif/inw_schuif_frameset.htm

also look at the 2nd video on the page for your version - although I still wouldn't recommend it, somebody has used brass for the cylinder there, he has a vid of it spinning with valve attached and no cylinder head.

Nick

 

[cl350rr]

your base... silly? I think not. It personalizes your engine in a way that makes it look unique. great idea and a really good looking engine.

R

 

[Fingers]

Thanks again everyone i must go now read all about troubleshooting I never saw this link before ;D will come in handy for tomorrow, hopfully the day i will try firing it up for a first run.
Regards J

 

[Fingers]

Just after reading the troubleshooting guide from above ,I must say my engine dose not run nearly as free as Jans horizontal type :-[

View attachment Testing for friction.mov

 

[NickG]

I wouldn't let it put you off at least trying it though. As I said, on the page for the type you are building there's a video of somebody elses engine he's put on. He does a test with and without valve and it doesn't run for nearly as long as the horizontal. I'm sure the vertical with the more traditional valve will have more power, having said that, it'd still be good practice to get the friction as low as possible.

Is your movie with the valve attached? Your type of engine has some noticable compression, or vacuum! The valve shuts before bottom dead centre presumably?

Nick

 

[Fingers]

Well Nick, no in my video the valve is not attached yet, I must be going blind also I can't find the video with a vertical type giving a demonstration. If you can explain where it is I would love to see it
many thanks
J

 

[NickG]

J,

the vid is on the right hand side, 2nd one down. The top one is Jans.
http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_happer_marc/happer_marc_frameset.htm

Nick

 

[Fingers]

Thanks Nick
For some reason that video dose not appear on my iPhone but checked on my laptop and there it was brass cylinder included lol I think it might be free enough fingers crossed, I managed to get some 1mm steel wire today for my valve springs. I'm hoping to make them and the final 2 bushes to connect the springs to the valves. All going well I will be trying for my first run tonight ,if I can figure out how to time it. Should the valve be at top centre while the piston is at the bottom of the stroke or is it a 90 degree offset like on a Stirling engine ?
Any help greatly appreciated regarding this timing
Regards J

 

[NickG]

not sure why they don't work on the i phone!

Can't wait to see it run, usually the valve should close just before bottom dead centre and open just before top dead centre on engines of this type.

I'm sure Jan will have better instructions on his website though.

Nick

 

[Fingers]

Thanks nick
Iv just spent the last 8 hours playing with this trying to get it to run, still no joy ???
ARrrrrrrrraghh!!!

 

[NickG]

J,

It's annoying, I had the same thing with mine as have many other people, but persevere!

You need to systematically go through the trouble shooting tips as for the other engine, it's a little different with yours though.

First step is, as we've discussed to ensure friction is as low as you can get it. Without the valve on there is no disruption to the airflow in and out of the port, it is a restriction but it should still do quite a few revolutions (I would aim for at least 15-20 with a strong flick of the flywheel.)

You don't want the valve to be a large source of friction either, your springs need to seal but with the least pressure possible to keep it flat against the port face - that's all. If it's flat, the vacuum will suck it against the face anyway.

The other thing with yours is the timing. The valve should be open as the piston is travelling down but should be fully closed a few degrees before bottom dead centre. If you've got the shape of the cam right, you shouldn't have to worry about anything else.

Then there's the burner - that port is very large and because it's horizontal it doesn't lend itself to getting a flame that will cover it. Make sure your flame is large - use a flat wick the same size as the port or fray your wick out a lot and leave quite a bit sticking out, you'll need a large flame as you can't afford to suck in any cold air.

Study the videos again and videos on u tube for any tips. Look in particular at the flames on the type I made, the internal valve version - they are massive!

You'll get there, hope this helps.

Nick

 

[Omnimill]

One of the things I noticed with this design is that the piston is very much longer on the vertical engine than the horizontal one. I noticed on my own internal valve engine that the piston binds in the cylinder if it's orientated vertically and suspect Jan noticed something similar before he designed the Marc vertical engine. I do wonder therefore if there is more chance of excessive friction using such a long piston. I also wonder if the full diameter of the piston has to run the full length or whether it could be relieved somewhat in the middle section?

Vic.

 

[NickG]

That sounds a good idea vic to relieve it in the middle, strange that it would be any difference vertically though, if anything there is less sideways force as the mass of the piston doesn't account towards the friction on the vertical.

Nick

 

[Omnimill]

Nick, I think the piston on the engines we built are a bit "too square" - the diameter is too large for the length.
If I spin mine over held vertically with the cylinder downwards it spins nicely, if I try the same thing with the cylinder pointed upwards the piston binds in the cylinder! scratch.gif This seems strange to me for an engine that runs nicely under flame. When I first saw the "Marc" plans I gave a the piston dimensions a nod as I figured it needed a long piston but the friction must be quite high if you're not careful. If I were building it I'd probably "modify" the design a little to make things easy for me! ;D I'm actually wondering if I can build an internal valve version in a vertical format? ??? - think I'll wait for you to try Nick ... :big:

Vic.

 

[Fingers]

Thanks guys
I think I have found the source of my problem, my brass! Cylinder seems to expand to much in the heat causing to much friction which I don't have when it's cold. I know it's the wrong material from listening to alll of your answers but I dont have time to make a CI one just yet so later on today I think I will try lap the cylinder out a bit more to try and compensate for expansion hopefully if I'm careful I can get them to work together. If I don't it will be the new year before I get back to make a new one :-
Thanks all, will keep ye posted
Regards J

 

[mklotz]

When the cylinder expands, the bore diameter increases. I fail to see how this could increase friction.

 

[Fingers]

Ok I'm listening carefully
This is where I stand I must be thinking wrongly, before I went to bed last nite when I was trying to get it to run it was turning nice and freely but now the piston is tight in the cylinder any ideas

 

[Fingers]

Hi everyone
I stripped down my engine last night and honed a little off my cylinder as i think the fit was to closeI still cant get it to run, I dont seem to be able to get the timing correct according to the plans. I am on my second cam now still no luck !
This is definitely not going to plan lol ,I'l just have to keep plugging away and troubleshooting.

View attachment friction 2.mov

View attachment testing friction.mov

 

[Fingers]

Thanks Pat
Persevere i will i just got my first run there now 8) it only lasted about 5 seconds but I know I'm on the right track ;D
.I have a question regarding my fuel 'methylated spirits' when i took the top of the cylinder after that little run it had what looked like a lot of water, anybody any idea why this would happen?
Kind Regards
Jamie

 

[Fingers]

Thanks for that Pat i taught maybe there was something wrong with my spirits ie water inside it