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jerry56 05-28-2022 08:34 PM

Shovel mechanics
 
On the old style mining shovels like this one
https://i.ytimg.com/vi/MDnxrDHvqoU/maxresdefault.jpg

Is the "stick" powered... or does it just slide through the boom as the bucket is raised and lowered....

Krewmember 05-29-2022 12:42 AM

Re: Shovel mechanics
 
Yes, the dipper handle is powered in and out on a shovel. Some use a rack and pinion some are cable driven others use chain along the dipper handle to a sprocket. Steam era shovels had a steam engine on the boom to drive the pinion, diesel and gas machines used a chain running down the boom to drive the pinion or sprocket. Check out the youtube channel "SteamCrane" lots of good footage of shovels in action.

It looks like the shovel in that image is a chain driven rack and pinion handle.

I hope this is of some help.


-Shawn-

jerry56 05-29-2022 08:44 AM

Re: Shovel mechanics
 
Yes a lot !!!
I've watched videos of them working and it looked like they were powered in various ways but you really couldn't see how.... Then some looked like it was just gravity ... I was hoping for gravity cause that would simplify things....now I have to figure out something small that will fit in a boom... I'll check out that site...
I like that Northwest Model 6.... and the Bucyrus-Erie 10B....
I don't have any machining capabilities so I'll have to do it all by hand or 3d printing so I have to keep it simple....

Krewmember 05-29-2022 10:13 AM

Re: Shovel mechanics
 
You are probably right about gravity being used to let the boom down. But the dipper handle needs side back to start a cut. I'm not claiming to be a expert on cable shovels, just trying to share what I have observed.

A rack and pinion mechanism would probably be easiest to 3d print and the most straight forward as you can have a motor direct drive the pinion.


-Shawn-

frizzen 05-29-2022 10:43 AM

Re: Shovel mechanics
 
I have seen several different crowd setups on the Dippers between brands of Facing Shovel / Power Shovel.

Old patent info is sometimes really helpful to see how it worked and what times various things became available. Scans of the machine setup manuals are also really helpful to see what's going on.

Which models are you thinking about?

Unit with Roller-chain crowd
https://youtu.be/PzEmF2GgP1g

Bucyrus-Erie looks like Cable crowd
https://youtu.be/3GQVXtvudok

Tech manuals like
https://constructioncranes.tpub.com/...1-12/index.htm
Specifically
https://constructioncranes.tpub.com/...201-120051.htm
And the next page that shows reeving diagrams

Krewmember 05-29-2022 11:29 AM

Re: Shovel mechanics
 
Here is some scans from my Bucyrus-Erie 22-B manual showing the cable routing and top-down view of the boom for the shovel.

The Bucyrus-Erie 22-B is a cable type machine, if you look at the cable routing two cables wrap around a pulley in the boom, one cable goes to the top of the dipper and the other to the bottom, when the drum at the pivot of the boom is rotated one cable unwinds and the other is wound pulling the dipper in or out.

https://i.imgur.com/rOKpcAZ.png

https://i.imgur.com/1lB4psq.png





-Shawn-

jerry56 05-29-2022 12:43 PM

Re: Shovel mechanics
 
I'm just in the very early planning stages and don't really know what I'm doing but I've never let that stop me before.....
First I'm not a rivet counter what ever I do will be a "representation" of an actual shovel...
I'm thinking this could be made to look similar to a Bucyrus-Erie 10B or a small Lima
https://live.staticflickr.com/65535/...c60cd84e_z.jpg
And this could be a Northwest 88B ish...
https://live.staticflickr.com/65535/...eb554b37_z.jpg
I know they are not perfect matches but to be honest I don't have the skills to make a perfect scale model but I think it would be fun and unique if I could make one work....
If not then I'll shelve the white shovel and make a cable hoe or dragline out of the green one.

frizzen 05-29-2022 01:24 PM

Re: Shovel mechanics
 
Since we're not rivet counting or wanting THIS exact model, it's possible to be much easier.

Before even getting into the power stick return parts, I might start by seeing how that Structo shovel can operate with something like just a dead-eye at boom tip, pulley on dipper by the bucket, pulley on boom tip, back to cable drum in house.
Maybe go a little heavier reeved so you get the 2 big sheeves by the bucket that looks like it was more common on the big machines.

It's not going to be as efficent at digging with bucket moving in a radius as the real ones pulling in an elipse, but it might not need that much engineering to work pretty well.

jerry56 05-29-2022 03:12 PM

Re: Shovel mechanics
 
That was kind of my plan in the beginning just make it work as best it can as the toy was built....efficiency isn't really important with this one just making it work with some pulleys and cables etc. I think it would look kind of cool with the pulleys spinning and actually loading dirt.
So do you think leaving the dipper fixed and just have a boom up and down and dipper up and down it would work ok.... I guess you would have to move up on the dirt pile to keep material in reach. Then I only need to design two drums and a mount for them...
Put some Bucyrus-Erie colors on it, I have a Huina lower track section I was going to use for the tracks....I think it would look ok...and work

frizzen 05-29-2022 08:14 PM

Re: Shovel mechanics
 
I've never run one.
Since you'll probably also use a cable drum to control the Boom, you should be able to use the stick Hoist and Slew to chew through all of the exposed face in reach, then lower the Boom and take another set of passes a couple times before you need to advance the machine.

It won't be quite as cool as having the stick wildly swinging around too, but also probably easier learning to dig with.

jerry56 05-29-2022 09:12 PM

Re: Shovel mechanics
 
Thanks for everybody's input it really helped me get this figured out.... now to order some parts from you know where so I can have them by Christmas....

Finster 07-07-2022 01:08 PM

Re: Shovel mechanics
 
Just in case this might be an option for you there is another type of cable front shovel. The dipper is fixed to the boom on a pivot point and the boom is raised lowered to position the bucket. Here is an example:https://www.youtube.com/watch?v=dl7ra-pp-u8 This type is found on old excavator cranes by Priestman, Dolberg and Fuchs to name a few.

jerry56 07-07-2022 03:21 PM

Re: Shovel mechanics
 
That's exactly what I was envisioning for this one....Just need to change the dipper a little so I can get the cables past the back side of the dipper arm but I think I can make this happen... thanks for that video...

frizzen 07-08-2022 11:03 AM

Re: Shovel mechanics
 
Cool video and great suggestion Finster!

IF i'm seeing this right you've got: Boom winch (3 sheeves), Crowd winch (2 sheeves), and a Bucket trip that just routes along both booms into cab
https://www.geograph.org.uk/photo/4037513

Priestman Wolf as dragline with clutches on cable drums to allow 'bucket casting'
https://m.youtube.com/watch?v=Nv1tj_5-8SM

Priestman Wolf digging with a 'Skimmer'
https://m.youtube.com/watch?v=Fkw0BT3hc-o

jerry56 07-08-2022 04:02 PM

Re: Shovel mechanics
 
Yeah it look like it's pretty basic.....

frizzen 07-10-2022 09:45 PM

Re: Shovel mechanics
 
I also just learned about the nylint ''Big Dig", which seems to mostly operate that way with a fixed dipper fulcrum, and without as much line-doubling since kids are high torque / low speed.

http://www.tnttoytrucks.com/NYLATECON1.html
If you're ok with a Michigan crane cab, or their later one with antiglare windows.

https://www.instructables.com/Toy-Steam-Shovel/
Detailed scratch build, kinda 1920s Marion?

jerry56 07-11-2022 05:29 PM

Re: Shovel mechanics
 
Yeah, Nylint used those for a couple different toys.... I have a couple that I plan on doing something different with .
That scratch build is slick, there is a toy like that and I've thought about doing it

frizzen 07-14-2022 01:39 PM

Re: Shovel mechanics
 
Still just teasers about the ''something different'' nylint cranes?

I've thought a couple times about scratch-building or finding one of the 1920s-style vintage toy Steam Shovels in Poor enough condition. Also seemed like it could be fun to do as a 'Mike Mulligan' book tribute "Mary Anne" power shovel instead of building it straight.
Plus running a Smoker unit to the smoke stack or cylinders wouldn't look all weird like a blown headgasket.

I've always really liked how versitle the old cable-machines could be: Crane? Clamshell? Dragline? Cable Hoe? Facing Shovel? Pile Driver? Skimmer? Yarder? Yeah...we've got ya covered.

jerry56 07-14-2022 03:38 PM

Re: Shovel mechanics
 
I think I've pretty much worked out the pulleys on each side of the boom tip that carry the cable down to the bucket... I'll 3D print them so if they wear fast I can just print more... But I need to print the pulley to mount to the boom and at the bucket, it will need to be in some sort of a housing or bracket ( not sure of the correct term) so the can swing freely ... I haven't worked out how I'll make the "bracket"... I'm sure it can be done but I just haven't figured out how I'm going to do it yet...
lol.. Yeah just teasers...I have some vast plans but just half vast ideas.....I don't build things fast... so I hate to say I'm going to build something then take 5 years to do it....lol

frizzen 07-17-2022 01:54 PM

Re: Shovel mechanics
 
This looks like it was a pretty common setup with the hoist dead-eye mounted on the buckets sheeve block.
https://www.equipmentjournal.com/vin...owered-shovel/

Something like this gear rack (2nd link) might be able to get the crowd control working seperately like (1st link, top animation)

https://handwiki.org/wiki/Engineering:Power_shovel

https://www.pitsco.com/TETRIX-Rack-a...ear-Slide-Pack


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