Author Topic: Chris's Marion 91 Steam Shovel  (Read 272577 times)

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #465 on: January 05, 2018, 11:11:04 PM »
This afternoon I got the other hinge plate recessed in, now both are ready to have the detail shaping done at the ends with an air rotary tool and dental bits. Hate the sound (flashbacks to the dental chair) but it works really well!
Here they are test fit on the bucket.

There is still a trim piece needed where the hinge goes onto the door, a wider flange at the transition point along the arm of the J, going across where the door rim sticks up where the slight gap is in this photo.

One of the hinges tipped up to show the range of movement. Its interesting how having the hinge pin offset means the door self-closes at an earlier angle, and also reduces the clearance to the ground needed.
« Last Edit: June 16, 2018, 08:46:01 PM by crueby »

Online Dan Rowe

  • Full Member
  • ****
  • Posts: 738
  • Dripping Springs TX USA
Re: Chris's Marion 91 Steam Shovel
« Reply #466 on: January 05, 2018, 11:21:33 PM »
Wow, Chris, that bucket looks amazing. Nice tooling plate I have one on my roundtuit list.

Cheers Dan
ShaylocoDan

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #467 on: January 05, 2018, 11:24:17 PM »
Wow, Chris, that bucket looks amazing. Nice tooling plate I have one on my roundtuit list.

Cheers Dan
Hi Dan, I'd move it up to the top of the list if you are milling odd profile parts - works fantastic, no slippage or wobbling at all. Wish I had made it a long time ago. Now I just need to tap the rest of the holes in mine...

Hmmm, those shop elves just vanished into the woodwork!!

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #468 on: January 06, 2018, 08:17:22 PM »
This morning I took the ends of the slots in the hinges down using a high speed air rotary tool and some dental burs, in the areas at the ends where an end mill would not fit:

Then some more time with the rotary table setup to mill slots for the hinges in some thin bars cut from some sheet brass. These will form the wider platform that the hinges mount to on the bottom door.

Test fit of the hinge - one snapped on with a friction fit, the other had just a slip on fit:

Next step was to mill the matching notches in the rim of the door for the plates to fit through. To hold this larger piece, I moved the center button and t-slot nuts over to the end position, since the door is too wide to fit between the bolt heads. I may countersink those holes to eliminate this issue for future parts.

And here it is with the second side notched in.

Next I'll get the plates riveted in place, then will trim the ends of the plates to be flush with the profile of the door.
« Last Edit: June 16, 2018, 08:46:13 PM by crueby »

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #469 on: January 06, 2018, 10:46:02 PM »
One more bit of work for today, drilled and riveted on the hinge base plates:

and a quick nibble on the belt sander to fair in the ends of the plates:

Next up is to attach the hinges, which will take some careful measurement and marking to get them lined up in the slots just right. Then, on to all the latch mechanism on the bottom of the door. Here is a shot of the original to show where all that will be going:

The chain in the upper right corner attaches to the pull-rope that goes back to the turntable. Pulling on that moves the levers, sliding back the large square bar at the bottom center of the photo, which pulls it out of the opening in the latch plate at the front of the bucket. All those levers give it some mechanical advantage - I would think there would be a lot of force needed to move the latch bar when the bucket had 15000 or 16000 pounds of dirt/rock in it!
« Last Edit: June 16, 2018, 08:46:20 PM by crueby »

Online Dan Rowe

  • Full Member
  • ****
  • Posts: 738
  • Dripping Springs TX USA
Re: Chris's Marion 91 Steam Shovel
« Reply #470 on: January 06, 2018, 10:57:56 PM »
What resets the latch pin...gravity?

Nice work.

Cheers Dan
ShaylocoDan

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #471 on: January 06, 2018, 11:22:29 PM »
What resets the latch pin...gravity?

Nice work.

Cheers Dan

That's right, the latch bar is a couple inches square and over a foot long, so quite heavy. The top corner is angled in, like the leading edge of a normal door striker, so it can be pushed up by the strike plate if needed. I've noticed that nowhere on the entire machine is a single spring, everything is gravity actuated. Even the return on the hoist drum brake band is a large counterweight on an arm. They have designed for reliability for many years.

Offline RJH

  • Full Member
  • ****
  • Posts: 10
Re: Chris's Marion 91 Steam Shovel
« Reply #472 on: January 07, 2018, 01:02:03 AM »
7.5 or 8 ton is a lot of rock. How many yard bucket is that?

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #473 on: January 07, 2018, 01:42:10 AM »
7.5 or 8 ton is a lot of rock. How many yard bucket is that?
The standard model 91 came with a 5 yard bucket, this one has the optional 2.5 yard bucket, presumably since it was digging limestone rock. The Marion company also could supply extra long booms, wide set wheels, etc for special needs of customers.

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #474 on: January 07, 2018, 07:01:33 PM »
More done on the hinges today. Drilled/tapped the hinges and door for some 1-72 bolts, the heads of which were then taken off more flush to look like rivets on the inside.

Here is a couple shots of the hinges in place:



Just took a slight bit of filing on the back bottom edge of the bucket to get it to swing free and close flat to the bottom.
Here is the bucket hanging straight, showing the angle that the door naturally hangs at. As you can see, the door swings back and up a bit, reducing the clearance needed underneath, but stopping at about a 45 degree angle (falling dirt/rock from the bucket can push it out vertically).

With that angle, they only had to swing the dipper boom back in at 45 degrees to get the door to swing closed, probably slightly more to get the latch to catch. A clever design.

Next up will be a start on the latch mechanism...
« Last Edit: June 16, 2018, 08:46:40 PM by crueby »

Offline Steamer5

  • Global Moderator
  • Full Member
  • *****
  • Posts: 1088
  • The "Naki" New Zealand
Re: Chris's Marion 91 Steam Shovel
« Reply #475 on: January 07, 2018, 10:38:20 PM »
Hi Chris,
 Them old fellas were a bit cunning!

Very very nice!

Cheers Kerrin
Get excited and make something!

Offline Don1966

  • Full Member
  • *****
  • Posts: 5969
  • Morgan City, LA (Along the Gulf Coast)
Re: Chris's Marion 91 Steam Shovel
« Reply #476 on: January 07, 2018, 11:45:54 PM »
Awesome Chris good attention to details. Still love it Dog..... :ThumbsUp:


 :cheers:
Don

Offline derekwarner

  • Full Member
  • ****
  • Posts: 481
  • Wollongong ...... Australia
Re: Chris's Marion 91 Steam Shovel
« Reply #477 on: January 08, 2018, 12:34:28 AM »
Hi Chris.....I think I understand the latching of the bucket door, and must assume that there are some levers or fulcrums functions employed to gain mechanical advantage....... however a few things escape me :facepalm:

1. is the yellow X a pivot?
2. is the red dotted line another parallel lifting bar?
3. is the green some form of limiting or pivoting adjustment point mechanism?

Derek
« Last Edit: January 08, 2018, 12:37:50 AM by derekwarner_decoy »
Derek Warner - Honorary Secretary [Retired]
Illawarra Live Steamers Co-op - Australia
www.ils.org.au

Online crueby

  • Full Member
  • *****
  • Posts: 8563
  • Rochester NY
Re: Chris's Marion 91 Steam Shovel
« Reply #478 on: January 08, 2018, 02:40:06 AM »
Hi Chris.....I think I understand the latching of the bucket door, and must assume that there are some levers or fulcrums functions employed to gain mechanical advantage....... however a few things escape me :facepalm:

1. is the yellow X a pivot?
2. is the red dotted line another parallel lifting bar?
3. is the green some form of limiting or pivoting adjustment point mechanism?

Derek
Hi Derek,

Yes, there are several layers of levers there that give it more mechanical advantage. I'll include a labelled picture from the 3D model, which should make it a lot clearer than the original with all the corrosion.

The latch bar A is pulled on by the cross bar, which has a fixed pivot next to the 'B' label. That bar is pulled on by bar C, which is in turn pulled on by bar D, which is restrained by the crossbar F which is fixed in position. Bar D is pulled by the chain, which attaches to the middle of bar E. The lower end of bar E has a ring to take a rope that goes back to the operator. Each of these bars is set up to increase the levarage on the latch. The bar D is anchored at the bracket G - the rod coming out of G is threaded, with a nut on each end - that will give adjustment to the linkages so that wear on the latch bar can be accomodated. G looks like a hinge, but it is just a threaded holder for the rod. I have not calculated it all, but it looks like the rope would have to be pulled by the operator several times farther than the latch moves, upping the force on the latch to overcome the weight of all that dirt/rock in the bucket. It must have worked well, this machine was in operation for decades without this being changed.

Hope that helps!
« Last Edit: June 16, 2018, 08:46:59 PM by crueby »

Offline 10KPete

  • Full Member
  • ****
  • Posts: 1559
  • Nordland, WA, USA
Re: Chris's Marion 91 Steam Shovel
« Reply #479 on: January 08, 2018, 05:02:12 AM »
That looks like about 12:1 total. How far into the latch hole does the bolt go??

Pete
Craftsman, Tinkerer, Curious Person.
Retired, finally!
SB 10K lathe, Benchmaster mill. And stuff.