William F. Skinner - 1939 Gravity Power

[armandino]

Video replica Skinner Machine

sorry I forgot to enter the video link.
good vision and let's hear

https://www.youtube.com/watch?v=HJMXDB5bF7o

[armandino]

[Danny B]

Concrete weights

Here is part 1 of a very interesting replication. He uses concrete weights and by part 4, he has to put a tether at the top of the weight. He works his way up to a system that goes from a circle to an ellipse. Part 5 wouldn't load for me so, I don't know the final step of his progress.

https://www.youtube.com/watch?v=00xIxEQqRsk

[Danny B]

hollow weights?

I'm playing around with my piece of solid round bar stock. It's 4" X 42". I'm convinced that the weights are NOT solid bar. There is only a bottom mount for a piece of steel weighing 175 lbs. The bottom mount is just too flimsy to stand up to the rotation that he uses. The top of the tall weight has a small rounded, raised lip and some kind of small protrusion in the center. I believe that the center protrusion is an attaching point for lifting.

In the vid, he moves the upper weight with his fingertips. I just don't believe that it is solid bar. Also, it swings back on it's own in a manner that tells me that the mass isn't all that high. At 9:01 to 9:17, it looks like the base of the upper weight is perforated with big holes.
So ???

[Danny B]

Thanks guys for the excellent video work. Huge improvement. It definitely looks like the upper shafts move in an elliptic. BUT, I'm somewhat at a loss. Starting at 7:45 in this vid, you can clearly see the 4 shafts. https://www.youtube.com/watch?v=mEat-8zOjlE
3 are moving and one appears to be stationary. I'm not trying to start an argument. I am in the process of building the full size machine with the full size weights.
Duh, the 4th shaft is hiding behind the closest shaft. What i thought to be a stationary, immobile shaft is a highlighted reflection off the corner upright member.

EDIT, at :50 you can clearly see that all 4 are moving; https://www.youtube.com/watch?v=mEat-8zOjlE
At 9:01 to 9:17 you get a good view of the bottom side of the weight. It kinda looks like the bottom has holes in it. At 9:11, it appears that there is some sort of cross plate on the bottom of the upper weight. Is the upper weight solid?
The upper weight has a much smaller support bar than the lower weight? I'm at the point of fabricating the "translation plate" Does anybody have a good guess at dimensions?

[BroMikey]

Thanks for the Video work.


[VIDEO]https://www.youtube.com/watch?v=mEat-8zOjlE[/VIDEO]



[VIDEO]https://www.youtube.com/watch?v=rxIRaJlTD4Y[/VIDEO]



[VIDEO]https://www.youtube.com/watch?v=lA9wHJsFzm4[/VIDEO]

[Aaron]

Skinner Machine Elliptical Input

Elliptical input:

https://youtu.be/JolNozy8UEY?t=34m52s

https://www.youtube.com/watch?v=lA9wHJsFzm4

[3758]

My latest / updated / revised / amended "Replication Investigation" video

https://www.youtube.com/watch?v=mEat-8zOjlE

[Danny B]

A few quotes

There seems to be some difference of opinion as to whether the shafts/weights move in a circle or in an ellipse..

"The "gravity power machine" stricKen about two weeks ago consists of a steel framework containing four shafts controlled by on the eccentrics. "
"controlled by on the eccentrics. On each shaft is an off-balanced weight which Skinner said was "about the secret of the whole thing." He explained that the shafts, turning in the eccentrics, "
"The one-eighth horsepower electric motor. Skinner said, was used only for power to turn the eccentrics and the "gravity power machine 'provided the power"
"He explained that the shafts turning in the eccentrics, moved the weights in a circular motion at 60 revolutions"
" of the weights to new centers of gravity caused by the changing positions of the shafts. The weights do not actually fall. The one-eighth horsepower electric motor, Skinner said, was used only for power to turn the eccentrics"

If you look at the bias on the gimbals, you can see that they are much longer than they are wide. This would suggest an eccentric rather than a circle. There is no reason to use his style gimbal. The new stuff is much better. Though the gimbal does carry the whole weight of the upper counter weight.

My lower weight is 4" X 42" steel bar stock. I'm still working out the ratio of upper to lower weight.

[artoj]

No Midget

Danny, Skinner is 66.36" in height, I drew a 3D/perspective computer projection to a resolution of about 1/8". All materials, bolts, pulleys, motors, shaft etc conform to the dimensions as presented. I was replicating all period materials as available in 1925-1939. I am an Artist and this was a way of clearing the speculation as to any mystery, as I see it, there is no more hidden aspects. Regards Arto.

[Danny B]

dimensions,,, again

Artoj, I have your dimensions on the links that you kindly sent. You give a weight / size of ; 5 3/4 X 7 for the upper weight and 4 X 33 for the lower weight. If you look at :32 in the vid, Skinner has his hand on the upper weight, https://www.youtube.com/watch?v=ObdM7VzE18A

http://i8.photobucket.com/albums/a28/DannnyB/CIMG2003_zpsy4bz31ux.jpg

Flight 33 Productions
No rest for the wicked.
EDIT, the photobucket picture for my woodgas truck is now listed as an attack page. WTF

[Danny B]

Mehmet, I'm pretty sure that Skinner made a lot of attempts before, he got his final design. He probably noticed the shaking very early. I'm finalizing design ideas,, in my head for the moment.
Plan "A" is it now stands is; build a 100 gallon water tank with an open top. From there, attach 4 uprights of box steel tubing. Then, 2 parallel steel plates to hold the 2 lower bearings.
The weight of the water will keep it from scooting around the shop. I'll use a variable speed motor for the drive. The output shaft, under the lower plate, will be connected to a water-wheel. I have a General Radio strobotach so, I can check rpm. I can use a dummy load to check adjustments.
I'm lining up constant-velocity U-joints,,, a must https://upload.wikimedia.org/wikiped...nimated%29.gif

Tracta joint; https://upload.wikimedia.org/wikiped...city_Joint.jpg
Tripot joint; http://mechanicaldesign.asmedigitalc...55504jmd1.jpeg
I'm leaning towards the tripot joint because I believe that it will take more weight than the Rzeppa joint. The Rzeppa joint is what you see on the front axle of your car. I'll slowly work my way up to the top. I don't have a very clear picture of the top yet.

[mksboysal]

mksboysal, that is quite a construct.
Artoj has extensive plans for a replication. Until I have a good working model, I don't want to multiply problems by 4. I plan to build a singlehttps://www.youtube.com/watch?v=Bp4t...ature=youtu.be
IF I find the time to work on this and IF I am successful, then, I will look at making the much larger quad machine. Good luck on your project.

Danny, it was said that: Great things are done more through courage than through wisdom. Applies to building this machine, some errors may show up but easily solvable. Building a copy and not a replica it's good thing. For the reason that you may have a resource for building materials and parts that might be free to get it or salvage it. Your comment on building a " quad device is that you should be able to cancel out some of the huge momentum swings" Great idea, William Skinner must have thought of that too, that's why his 5th generation machine the 1 min. clip that is available today works so smooth.
"Armandino bolted his device to the wall" excellent idea, if you have a place to make it permanent installation, you can resolve a lot's challenges by doing it so.

[Danny B]

The best mechanical OU devices seem to shake like a demented banshee

mksboysal, that is quite a construct. I believe you are in Hawaii. I'm sure that it is more difficult to find parts there.
Artoj has extensive plans for a replication. Until I have a good working model, I don't want to multiply problems by 4. I plan to build a singlehttps://www.youtube.com/watch?v=Bp4t...ature=youtu.be
IF I find the time to work on this and IF I am successful, then, I will look at making the much larger quad machine. Good luck on your project.

[mksboysal]

Skinner Replication

Hi guys,
The machine that are being discussed here I built it, it took me around four months to come to this completion, not finished yet. Enjoy the pictures. Frame size is 5 ft by 5 ft and the height is around 7 + ft. The lower weight is 340 lbs and the upper weight is around 75 lbs. As you can see the upper weight it's totally adjustable, you can slide back and forth if you want to. The driver motor is a 3 ph 1/8HP with a 56:1 gear ratio planetary gear it is controlled with 1/4 HP VFD drive. When I turn this thing on it's scary to stay close by! So I stand back 5,6 ft away when that 340 lbs rotates at 33 rpm or little higher you have to respect the "force in motion" under no load prime mover motor consumes 80 to 90 watts, the output power is still being tested!!! During the operation the frame sways a little but I have plans to make it firmer by installing cross braces all around the frame. Come along tool is temporarily hold the lower weight and does a good job with it. 90 decree weight lowers the input power close to 25 to 30 % anyway if you have a ? or comment drop me a line. If some of you need help? I maybe be available to help you design yours.