Author Topic: E-gad, he’s making another one of those crazy pop-up things  (Read 17886 times)

Offline cnr6400

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #135 on: May 16, 2021, 12:05:27 PM »
 :ThumbsUp: :ThumbsUp: :ThumbsUp: :popcorn: :popcorn: :popcorn:
"I've cut that stock three times, and it's still too short!"

Offline Vixen

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #136 on: May 16, 2021, 03:33:37 PM »
Hello Craig,

Great progress, It looks good with the paint job.  :ThumbsUp: :ThumbsUp: :ThumbsUp:

You will soon have it popping up and down like a crazy thing,

Mike
It is the journey that matters, not the destination

Sometimes, it can be a long and winding road

Offline crueby

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #137 on: May 16, 2021, 06:15:14 PM »
Love the paint job. As Mike says, will be jumping soon, like a robot Pez Dispenser!    :popcorn: :popcorn: :popcorn:

Offline Roger B

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #138 on: May 17, 2021, 04:38:18 PM »
That's some excellent fabrication/machining  :praise2:  :wine1:
Best regards

Roger

Offline Art K

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #139 on: May 18, 2021, 02:27:43 AM »
Somehow a robot Pez dispenser sounds like a scary proposition.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Craig DeShong

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #140 on: May 18, 2021, 09:49:09 PM »
Thanks for stopping by.  Achim, CNR, Mike, Chris, Roger, Art; thanks for your generous and encouraging comments.

As Mike says, will be jumping soon, like a robot Pez Dispenser!    :popcorn: :popcorn: :popcorn:
Somehow a robot Pez dispenser sounds like a scary proposition.
Art

I think I’ve found my next project!  :Jester:


Next was the task of fabricating the two eccentric straps.  These are made of brass and with a thickness of nearly ½ inch and a diameter of over 2 ½ inches, I was looking at acquiring a LOT of brass.  Have you priced brass lately?  >:( 

Putting my thinking cap on; I came up with a plan.   :thinking:

Remembering how I managed to get Chris’s elves to pilfer his inexhaustible supply of brass some time ago I thought I might be able to work the same deal again. :naughty:  I call the elves and stated what I needed, but when I mentioned “mint chocolate chip cookies” as the reward they laughed and hung up. :headscratch:  I really don’t know for sure what has changed, but I have my suspicions.  We all remember the Mann Wagon Chris just finished, with the “cosmetic” barrels in the truck bed.  He swore they were empty.  Maybe he thinks they are but I’ll bet those mischievous elves of his have filled them with some kind of “elf joy juice” they’ve brewed with a few pilfered parts from the Holly Pumping engine he’s currently building. :DrinkPint:   They all probably pile into his Mann Wagon and the Lombard Hauler and head out to the Adirondacks for a fun filled weekend of debauchery every once in a while; so Chris, if the Mann Wagon and the Lombard Hauler have gone missing a few weekends recently… well, now you know where they’ve been. :ROFL:

Of course all this hasn’t helped me with finding a bar of brass and I ended up going to the store and buying a bar…  on with the build.

Firstly, I wanted a smooth mating surface for the two eccentric strap halves.  The photo below shows my solution.



Next I needed to cut away the material where the screws that attach the two halves of the strap reside.  Using a stop and repeating the same procedure assured me that everything would be in alignment.



Next I drilled the holes for the connecting screws in one of the strap sides and drilled and tapped the other strap side.



With the two halves joined with the attachment screws I cut away the center to form the inter circle of the eccentric strap.



Next was to form the interior slot where the alignment ring on the eccentric will ride.  I'm using a woodruff keyway cutter to accomplish this.  You might wonder why I’m using my rotary milling head instead of a turntable.  I thought about using a turntable but with the setup I’m using I can “trial fit” the eccentric strap to the eccentric and return the strap to the mill and I haven’t lost my setup.  This would be difficult to do using a turntable.



With the interior work on the eccentric strap complete I’ve moved to finishing the exterior.  Here I’m milling a protrusion that will be used to attach the push rod for the slide valve.



 Now I’ve moved the work to the turntable to finish the exterior work.  The following two photos show completion of the exterior work.





The above covered the eccentric strap that operates the slide valve.  There is another eccentric strap that lifts the piston/rack.  The fabrication procedure was similar so I didn’t take any photos while making it.  I had thought I’d taken a photo of the completed eccentric straps before assembly on the model.  If I did, the camera didn’t save it.

Below is a final photo of the two eccentric straps mounted on their eccentrics on the engine.

Craig
The destination motivates us toward excellence, the journey entertains us, and along the way we meet so many interesting people.

Offline crueby

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #141 on: May 18, 2021, 10:24:16 PM »
That would explain the tire tracks down the front hall...

Offline Art K

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #142 on: May 19, 2021, 01:52:40 AM »
Great all we need is a bunch of inebriated elves with a truck load of Elfsteiner running around the neighborhood. Yeah, and you thought they'd confine themselves to your neck of the woods.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline crueby

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #143 on: May 19, 2021, 02:02:27 AM »
Great all we need is a bunch of inebriated elves with a truck load of Elfsteiner running around the neighborhood. Yeah, and you thought they'd confine themselves to your neck of the woods.
Art
Well, I do have relatives in Wisconsin... Maybe they are visiting them.


Anyway, back to the Egad build!

Offline Craig DeShong

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #144 on: May 19, 2021, 11:30:59 PM »
Thanks for stopping by.

Not a lot to report today.  I completed the valve mechanism by adding the pushrod that connects the valve eccentric strap to the slide valve as you can see in the photo below.


Next I have a handful of parts to make to arrest and control the movement of the ratchet/pawl mechanism.  Once this is done, I have the ignition circuit and trip to address.  With both those complete I might be able to give the engine a try, though it won’t be governor controlled till I build the governor.
Craig
The destination motivates us toward excellence, the journey entertains us, and along the way we meet so many interesting people.

Offline cnr6400

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #145 on: May 19, 2021, 11:57:09 PM »
 :ThumbsUp: :ThumbsUp: :ThumbsUp: :popcorn: :popcorn: :popcorn:
"I've cut that stock three times, and it's still too short!"

Offline 90LX_Notch

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #146 on: May 30, 2021, 09:39:45 PM »
You’re getting very close Craig.  I eagerly await the first ”pops”.
 
-Bob
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My Engine Videos on YouTube-
http://www.youtube.com/user/Notch90usa/videos

Offline Craig DeShong

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #147 on: May 30, 2021, 10:38:35 PM »
Thanks for stopping by.  CNR & Bob; thanks for your encouragement and comments.

I’ve built four of these “crazy pop-up things” at this point and I’ve consistently found there are two challenging areas on the build.  First was addresses up thread and concerns getting the piston to fall to the bottom of the cylinder under its own weight, but still maintain a “relatively” air tight seal.  The second I’ve been addressing over the last week or so and that issue is getting the pawl and ratchet to engage cleanly without skipping and to have them dis-engage completely so that the pawl doesn’t chatter against the ratchet.  With each model in the past this has taken a bit of thinking and tinkering; and in some cases a re-design of the pawl release mechanism.  This engine was no exception.  My third re-design of the pawl release mechanism seems to be working well.  The full test is when the engine is running.  I’ve also found that this mechanism, that seems to work flawlessly when the engine is turned over by hand, can develop problems when the engine is running on its own at speed.  In that regard time will tell.

Before I can have a first test I need to build the ignition circuit yet and I’ll need to get more acetylene, since I exhausted my supply in surface-hardening the ratchet and pawl mechanisms to discourage wear.

I’ve made a video I present below which describes the current state of the model and hopefully, give you some insight into the mechanics of this engine.
<a href="https://www.youtube.com/watch?v=0DJPt7oLv-Y" target="_blank">http://www.youtube.com/watch?v=0DJPt7oLv-Y</a>
« Last Edit: May 31, 2021, 03:44:00 AM by Craig DeShong »
Craig
The destination motivates us toward excellence, the journey entertains us, and along the way we meet so many interesting people.

Online Kim

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #148 on: May 31, 2021, 05:44:47 AM »
Very interesting video, Craig!  Thanks for walking us through that.
These are sure interesting engines!

Kim

Offline Art K

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Re: E-gad, he’s making another one of those crazy pop-up things
« Reply #149 on: May 31, 2021, 03:57:36 PM »
Looking good Craig, It was good to see the video showing the ratchet & pawl mechanism at work.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

 

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