Duplex Vacuum, (Heinrici type stirling)

[joe d]

Dean

Another one that was a pleasure to follow along, and the end result was well worth the trip!

Nice work, Sir :bow:

 

[Deanofid]

Sam, Kevin, Kel, Gail, Ron, Arv, Bill, Dennis, Arnold, Joe;
Thanks again for so many kind remarks!

Not My First Failure!

I hate to say it, but I have a case of Zee's bumness today. I got the new o-ring for the fan. That's the
only positive thing that was done, though.

I said I'd have a video today. I should have just said "soon" so I wouldn't make myself a liar.
Apparently, I got something out of whack while assembling after all the paint work, and it just
doesn't want to run well at all.
I have four other videos of it running just fine before it was painted, one of which was put up
here a few pages back. I haven't figured out yet what I'm missing in the set up process that
I didn't miss on previous runs. After a few hours of changing piston timing, crank timing, checking
bearings for tight spots, and etc., etc., I was getting a bit of a frownie face, so decided to set it
aside for a day. These things happen. I have a fair number of engines under my belt, and I
know things simply don't go right sometimes. It's one of those times, guys!

I'll be back! A day or two spent twiddling things will work wonders. Especially when I go at it
in a better mood.


For what it's worth, it did run for a short time, but I didn't think to grab the camera until after I'd just
turned off the burner. This is a very short vid of it winding down, running a few seconds on residual
heat.

Sorry for the disappointment. It'll get better!

Dean



[ame]http://www.youtube.com/watch?v=J7IDrUC_7mU[/ame]

 

[SAM in LA]

Dean,

I'm confident that you will find that little gremlin that is hiding in your engine.

You didn't use E85 for fuel, did you?

SAM

 

[Twmaster]

A little shot of 'Gremlin Be Gone' and all will be well!

 

[ksouers]

Must be the day for Gremlins, Dean. I had them all day at work, as well.

 

[zeeprogrammer]

a case of Zee's bumness today.

Careful there. That kind of stuff can stick with a guy. I don't want to be known as spreading 'Zeep-itis". ;D

Did you try running it without the o-ring?

I'm sure it's going to be easily taken care of.

Turn that frown upside down. (Where the heck have I heard that?)

 

[Deanofid]

I'll be looking for the gremlins, guys!

Zee, I don't think it can stick to anyone. If it could, a lot of us here would have the same nick name.
At least it's not something like Throat-Warbler Mangrove. Really wouldn't want that to stick.

Yes, I tried it with and without the o-ring. Something else is amiss, as it ran like crazy previously.
Just a bug or two. May have found one of them, and the arrow in the pic below shows another
part I suspect:

It's all fun 'n games. Pretty sure I can fix almost any part in it! ;D
Dean

 

[doc1955]

This is just a thought Dean wasn't the door missing (not built yet) on first run?
Maybe it is the heat isn't drafting the same. Just a thought.

 

[Deanofid]

That's good thinking, Doc. I'll be checking that out.
Thanks.

Dean

 

[zeeprogrammer]

As they say in my business Dean, "That bug is sweating now."

 

[NickG]

You'll get there dean, could be a draft thing.

There's no chance of the displacer leaking since you reassembled is there? I found that to be the problem on my stirling engine not only when I was trouble shooting but when I got a sudden drop in performance one day, but my sealing arrangement probably wasn't as good as yours.

Nick

 

[kcmillin]

I'll be looking for the gremlins, guys!

You didn't feed them after midnight, Did You? :big: :big: :big:

Im sure you will get her figured out. Maybe she's just a little shy in her new dress. :big:

Although this Gremlin isn't very shy at all.
http://cache.gawker.com/assets/images/io9/2009/04/gremlin.jpg

Kel

 

[arnoldb]

I think I see your problem Dean ;D - You must have some bug poop in one of the bearing joints; that just does not work for lubrication...

Seriously though, have you tried running it as-is but without the O-ring to drive the fan to see if it runs like earlier?
You added the drive pulley, belt drive and fan - and from your video the o-ring belt looks like it's "slapping" about which will add "funny" varying loads to the engine's main shaft. Just a thought from a complete newb who still want to build a couple of stirlings in future - so just add a pinch of salt!

Kind regards, Arnold

 

[Deanofid]

Thanks for the comments, fellows!

As they say in my business Dean, "That bug is sweating now."

Hope so, Zee!

There's no chance of the displacer leaking since you reassembled is there?
Nick

Hi Nick; That's a good thing for anyone to check if they're having striling troubles. I did check it
by putting it in water at near boiling temp. No leaky.

For others wondering about the boiling water thing, if a displacer can has a leak and you put it in
very hot water, bubbles will come out at the point of the leak(s).

Seriously though, have you tried running it as-is but without the O-ring to drive the fan to see if it runs
like earlier?
Kind regards, Arnold

Hi Arnold; I did try it a number of times without the belt, thinking it was causing the trouble. The vid
with the belt wobbling was on one run that I had put the belt on the wrong pulley groove.

Yesterday, before quitting for the day, it did run each time I tried it, a total of about seven or eight tries.
Just didn't run very well at all, barely keeping itself going for a minute before stopping.
After each attempt I had to let it cool down for half an hour or so in order to start from cold. On all
those tries, I concentrated on timing events thinking I just had something a little off from the
reassembly, or from running the fan.

I didn't get to mess with it today. It was put off by paying jobs. It's in pieces now, and I think I know
what's wrong. I'll tell about it, what ever it turns out to be. We'll see what tomorrow brings!

Thanks all, for the suggestions!

Dean

 

[Deanofid]

HA! Figured out what the problem was.

One of the crank throws came loose at the main rod journal. Was hard to see it when the engine
was assembled, because the crank uprights kept things lined up pretty well. When grasping the
flywheels in each hand and turning opposite directions, I could feel a little catch, like it wasn't solid.

It wasn't!

So, I got them lined up and held in a vise, then drilled and pinned them. More better.

Now it runs just like it did in the test run before I had painted it, though somewhat quieter
since it's now on a base with felt feet.

Here's the vid. I started it off without the fan belt on, and when it was going, put on the belt.

A funny thing will happen right after I put on the fan belt. I thought it was funny, anyway!
About halfway through the vid, I set down the camera for a few seconds to put on the belt.
Watch the fan.




[ame]http://www.youtube.com/watch?v=cArNQX7CVxk[/ame]


I had put the fan shaft in with Loctite. The bushing that holds it gets pretty hot! We
know what happens when we heat Loctite! It looses the 'tite' part of it's name!
I'll make up a new fan shaft with a press fit... later.

Thanks to everyone who followed along. This engine is done.

Dean

 

[zeeprogrammer]

Congratulations Dean.
That is a fine looking engine.
And this was a great thread...so much to learn.
Thank you.

This engine is done.

Oh really?

I sometimes wonder if an engine is ever really done. I suspect many of you think you've finished but I bet you ask or say to yourselves...
"hm I wonder how it would work if I..."
"hm wished I'd done...it would..."
"hm..."

 

[Deanofid]

I sometimes wonder if an engine is ever really done. I suspect many of you think you've finished but I bet you ask or say to yourselves...
"hm I wonder how it would work if I..."

I kind of already went that direction with the fan. It wasn't part of the original prints.
You see how that turned out... Got spit out like a black olive from a martini!

Thanks Zee.

Dean

 

[kcmillin]

Congratulations Dean on a fine build and a beautiful Engine. :bow: :bow:

your right, that was kinda funny when the fan came off. Reminds me of many many times in the shop with "Experimental" devices. Its just a learning experience, and Im glad you shared it with us.

Kel

 

[ksouers]

Hey Dean, I kinda liked the fan.

Though I rather expected it to take off like one of those old pistol toys that wound up a propeller then released it.

Glad you found the problem, and that it was a simple solution.

 

[Twmaster]

That fan has so much power it pulled it's self right off of there!!

I too am glad you got the issue sorted out.

Methinks maybe the loctite was trying to tell you something on both those 'events'.