Jan Ridder's Pulse Mobile

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Nice looking engine. The flywheel itself seems to be almost frictionless, but with the piston rod connected I see that the flywheel stops at random positions. It appears to me that the piston has either to much friction or is too loose inside the cylinder (no compression). It’s perhaps an optical illusion, but I also have the feeling that the restrictor is not fixed hardly to the test tube?
 

Thanks Guys,

I think the fit is good but I'll try a looser piston. The restrictor has springs around it to hold it in place. I think it's pretty secure.
Maybe I'll try to rearange the packing?... ???

KB
 
kustomkb said:
Thanks Guys,
I think the fit is good but I'll try a looser piston. The restrictor has springs around it to hold it in place. I think it's pretty secure.
Maybe I'll try to rearange the packing?... ???
KB
How tightly packed is the steel wool-stuff? Does air need to flow through it for that engine?
 
Hi Kevin,

I've had a little time and have been reading about this on Jan's site.... It seems that you are not the only one who had trouble with setting this engine up!

I suppose you have read this already? But thought I'd put a link here to help others understand what you are up against!

http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_thermo_acoustic_mobiel/acoustic_frameset.htm

It seems that there are very critical points in several areas of this conundrum ???



Good luck!!


Ralph.
 

Thanks for all your ideas and encouragement,

Tuned it a little more last night. I used a piece of glass tube with an end plugged and am wondering if the shape or it bieng one piece of glass has anything to do with it? I am still trying to find the correct tube...

I looked closely at some of the other videos online and it seems we all have the
same grade and consistency of steel wool.

The saga continues...


http://video.google.ca/videoplay?do...i=_DB3ScPkCqGG_AGG1_SsBQ&q=pulse+mobile&hl=en
 
I followed the link Ralph posted and read about the engine.

A couple of questions. Did you use the same material for the ring that holds the glass tube as Jan did and is it the same size? Reason I ask is that in his description he feels that is were the cooling/heating takes place.

Have you tried changing the the steel wool to a different size? From what I can tell from the pics and video of your engine and Jan's, it looks like there are two different grades of steel wool being used. Yours looks to be courser.

Have you tried just putting the piston in the glass cylinder to see what happens. See if it will move without being connected to the flywheel. From the action that Jan describes I'd say the piston would oscillate back and forth in the cylinder.

Regards,
Bernd

P.S. Just posted this after your post. Disregard the steel wool.

P.S.S. I guess my last question I has sort of been answered. A bind in the flywheel. I think you've just about eliminated all but the tube. So perhaps it's the tube that's causing your problem.
 
I built my own version of this engine.

http://www.homemodelenginemachinist.com/index.php?topic=2106.msg17090#msg17090

I used Jan's plans as a guide but altered things to fit the materials I had to hand and made changes to facilitate experimenting with various things. Mine runs but it's finicky and frustrating.

Just a few observations based on my build of this engine...

I seriously doubt that the shape of the end of the glass tube is important. Ignore that for now.

The size of the hole in the restrictor is important. I made my restrictor to accept interchangeable bushings so I could try different size holes. Consider making up two additional restrictors - one 25% larger (in area) hole and one 25% smaller than what you're using now. Try these and see if one of them brings the engine closer to running. If it does, make two more with a similar up/down variation from the size of the one that improved things and repeat the experiment.

In mine, the distance between the restrictor and the piston at TDC affects performance.
I made the mount that supports the test tube adjustable so that this distance could be easily tweaked. You might want to experiment with that.

I can't prove it but it seems to me that this engine has very little power near BDC. To me this implies that the flywheel needs lots of inertia to carry through. You might want to try a larger flywheel.

On mine one needs to really give the flywheel a good spin to get it running. I've considered, though never tried, using a rubber wheel in an electric drill to spin it up for startup. Perhaps something else to try?

Good luck in your efforts. I hope you can get it running. You'll be very proud when you do. The engine's mind-boggling simplicity and total absence of valves will astound your mechanical friends.

Please keep us informed about your progress. I'm sure there are many forum members and lurkers who are interested in what you are doing.



 
Thanks again for everyone's input.

Tonight I will try some finer steel wool that is more tightly coiled. (Big box didn't have any last night)

I thought of trying without the flywheel and then went down a different tangent. Thanks for the reminder.

I will make a couple bushes to alter the restrictor also.

I used the piston to push the restrictor into place. Maybe a few thou' further?

The engine's mind-boggling simplicity and total absence of valves will astound your mechanical friends.

I agree! that is what drew me in when I first saw them.


We'll get 'er beat yet.

Thanks,

-Kevin.
 
"We got action" says it all!! ;D

Congratulations Kev. That was a hard-fought win.

Loved the dance, as well. My wife was wondering what I was laughing at ;D


 
Congrats Kevin!
Looks and sounds GREAT!

Rick
 
Kevin,

Winners are Grinners - Congratulations on a runner and your persistence and patience in seeing it through to a very successful conclusion.
smiley-excited001.gif
smiley-happy014.gif

:bow: :bow: :bow:

I don't know which I enjoyed most the engine running or your obvious delight at achieving a runner.

Best Regards
Bob
 
Well you certainly can't top that much excitement ehh!? :big:


Nice runner you Got there Kevin :bow: ;D



As you said, "the mobile part to do" and it's a sweet victory well earned ;)



Looking forward to seeing this all working as it was intended :)




Ralph.
 

HEY !
Big congrats on a fantastic piece of work. Can't help but admire your perseverance (and Amanda's) that sure is a great runner.
It just goes to show that with the right encouragement and the right person at the controls, Even the insurmountable is overcome.

:bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow:

Kind regards

Malcolm
 

Thanks alot fella's!

After posting that first vid I knew I had to see it through to the end, I'm just glad it came as quickly as it did.

My wife was wondering what I was laughing at

My wife over heard the video and said "you're not going to post that are you?", "yeah?" , "but you sound like such a dork!"

Well dork's and nerds have invented the coolest things so sign me up!

Started a replacement base to stiffen and align the parts better, then will start on the "mobile part of the deal"

Thanks again for all the advice and encouragement. :bow: Truly a great feeling when it comes to life!

-Kevin
 
Congratulations, Kevin, and well done!

Tell your wife that your "dorky" excitement and dance are hardly unusual among the viewers of your achivement. I'll bet most of us have had similar moments. I know I have.

It's particularly true with this engine design. With a more conventional air or steam engine one can be fairly sure at the offset that, once built, the thing will run given enough pressure. Not so for these engines. One invests a lot of construction time with no assurance that the thing will ever perform. When it does it's only natural that a little victory dance is in order.

Now that you've got it running can you point to any actions you took that you think made the difference between not running and running? Given the fussiness of these engines, I'm sure current and future readers contemplating a build of this engine would appreciate any wisdom you can impart.

 

Thanks Marv.

I am drawn to stirling, flame lickers and now this style of motor because they are unconventional and can be placed on the coffee table, strike a match and away they go. Self contained. Steam is great too but I have not built a boiler as of yet. Compressed air motors are nice and reliable but until I plumb a line into the house...

My problem with this build (and others) is that I always make things too tight. After intoducing Clarence to the yoke holes and dropping the height of the flywheel to align properly, things were freed up considerably. With everything being such a snug fit, throw in the flexing sheet metal base and there was absolutely no forgiveness. I had thought the resistance was the air compresion. also after changing out the wool, I packed it longer than specified and had a few loose threads protruding into the transition area. I dont know what difference this makes if any. My Dad is a pro wood turner so I am thinking of asking him to make the base. Or go With Al, not sure yet.
The piston fit was such that with the con-rod connected and the tube held vertically, it would slowly fall out under its own weight.

Have fun!

Kevin.
 
Kevin: Good On You!!! That is a very good achievement and a admirable ambition to keep at it and get things running.
I think my grin was almost as big as yours when you were so excited that it was running under it's own power.
Quite a exciting video, thanks for posting it, really like to see anybody get their models running.
Thanks----don
 
Kevin I can't stop watching that video.
I brings an ear to ear grin for me every time!

Is that the smell of a Project of the Month I'm getting here?

Rick

 

Thanks again boys!

I'm pretty stoked to have another runner, Maybe have 'er piroeting by the weekend.

She says "why dont you put a balerina on top of the spinning part"

I made a beefier base, similar to one that I saw on you tube, today; Not a big fan of bent sheet metal,

thermo%20pulse%20mobile%20005.jpg


thermo%20pulse%20mobile%20017.jpg


enjoy!

KB
 

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