Author Topic: Chris's Build of Steering Engine  (Read 52242 times)

Offline steam guy willy

  • Full Member
  • *****
  • Posts: 3239
Re: Chris's Build of Steering Engine
« Reply #540 on: November 24, 2022, 10:34:51 PM »
Hi all ...I think we should thank Thanksgiving to Chris for being on this forum and sharing :) :cheers: :ThumbsUp: his wonderful models and skills with us all !!

Thanks

Willy

Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #541 on: November 24, 2022, 10:39:44 PM »
Hi all ...I think we should thank Thanksgiving to Chris for being on this forum and sharing :) :cheers: :ThumbsUp: his wonderful models and skills with us all !!

Thanks

Willy
I get just as much from all the builds and everyone sharing techniques, its a great group here!   :cheers:

Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #542 on: November 25, 2022, 05:23:19 PM »
Moving along on the bearings today - these bearings are square outside with a flange to fit over the sides of the holders, and are split into top/bottom halves. Lots of ways to make them, what I settled on was to make the top and bottom halves separately since the halves just fit into one of the sizes of bearing bronze rod that I have on the shelf. So, turned the outside of the rod to the fit a 17/32" collet (the bronze is made as a continuous case round, and the outside is oversize and rough) and then milled two sides down to the thickness. I alternated milling on each side, turning the collet block over so all the cuts were made on the same side, so the resulting block was in the center and no warping from any stress that may have been in the rod.

Once the rod was reduced to a rectangle the size I wanted, it was set up in the mill vise to slot one of the wider sides to fit the holders:

Some space was left between each slot to saw them apart later and trim the flanges down to thickness. Then turned the block up on its side to mill the matching slots in the sides, so the block would fit down into the holders. This was a fiddly operation, needed to get each side to match up with the existing slot in the first side.


After a lot of milling and fit testing, here is the block ready to saw apart into the top/bottom halves:

and a top view:

Next up will be to saw apart the bearing pieces, trim them to length, and drill/bore the holes for the crankshaft. The plan is to do that on the lathe with one of the bearing holders held in the four-jaw chuck. Once the opening in the holder is centered up, each bearing pair will be put in by backing out the jaw over the holder opening, clamped back in, then doing the drill/bore operation. That should ensure all four pairs are bored in a matching line, as long as I keep them all oriented the same way through the operations. That way of holding should also work for trimming them to length. Pictures on all that after it happens...

Offline cnr6400

  • Full Member
  • *****
  • Posts: 2731
Re: Chris's Build of Steering Engine
« Reply #543 on: November 25, 2022, 05:30:44 PM »
 :ThumbsUp: :ThumbsUp: :ThumbsUp: :popcorn: :popcorn: :popcorn:
"I've cut that stock three times, and it's still too short!"

Offline Michael S.

  • Full Member
  • ****
  • Posts: 1110
  • Germany, Saxony-Anhalt, Magdeburg
Re: Chris's Build of Steering Engine
« Reply #544 on: November 25, 2022, 05:36:47 PM »
I'm again very impressed how rich your ideas are to produce parts in series.
Excellent!

Michael

Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #545 on: November 25, 2022, 05:58:25 PM »
I'm again very impressed how rich your ideas are to produce parts in series.
Excellent!

Michael
Its another thing I learned from Kozo's book when building his New Shay design - much easier to work on longer bars and saw them apart at the end than to try and line up small parts for each operation and get them to come out the same. He uses jigs wherever possible - it was a great lesson when I was making dozens of each part for the tracks on the Lombard and Marion models.

Offline kvom

  • Full Member
  • *****
  • Posts: 2649
Re: Chris's Build of Steering Engine
« Reply #546 on: November 26, 2022, 11:59:34 AM »
When the crankshaft reverses, do both engines reverse, or does one run while the other free wheels?

Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #547 on: November 26, 2022, 01:27:25 PM »
When the crankshaft reverses, do both engines reverse, or does one run while the other free wheels?
Hi Kvom,
Both reverse together just like any two cylinder steam engine. The steam from the control valve goes to both steam chests, switching both between inside and outside admission, and the eccentric on each handles the timing of the piston valves.

In this picture from the CAD drawing, you can see the pipes arching from the control valve in the middle out to both cylinder steam chests on the ends:



Since its a top view, it shows as one pipe - this picture you can see both pipes going to one of the cylinders. The upper pipe goes to the center of the piston valve, sending steam there makes it inside admission. The lower pipe goes to the the space below the piston valve, which has a passage up the center so it fills the space above the piston valve as well. Sending steam there makes it outside admission.




Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #548 on: November 26, 2022, 04:28:07 PM »
Continuing on with the bearings and holders, the bearing blocks were sawn apart and slipped into the holders:

Made up a set of caps for the holders by drilling a longer bar and cutting them apart

bolted up ready to start trimming


trimmed the caps to length

and trimmed the bearing sides

Next step is to drill the holes for the crankshaft. Yesterday I was thinking of using the four-jaw on the lathe and drilling there, but a quick test showed that was not repeatable enough, so I'll set up on the mill and drill them there instead.

Offline Don1966

  • Full Member
  • *****
  • Posts: 6817
  • Columbia, MS
Re: Chris's Build of Steering Engine
« Reply #549 on: November 26, 2022, 05:11:16 PM »
 :Love:


  :drinking-41:
Don

Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #550 on: November 26, 2022, 05:59:54 PM »

Online crueby

  • Full Member
  • *****
  • Posts: 18559
  • Rochester NY
Re: Chris's Build of Steering Engine
« Reply #551 on: November 26, 2022, 06:13:58 PM »
I went through a number of options for how to drill all the bearing holes to match, and settled on a finger clamp that I first made several years ago to hold all the track plates for the Lombard Log Hauler for milling/drilling. Its been modified and reused for a number of other models since then, here is once more. I milled in a new set of shallow recesses for the bearing blocks to slide into, and have them all marked so they all will go into the fixture in the same orientation. Then got the jig set in the milling vice and positioned for the first one. After that it was just a matter of loosening the top screw and swapping the parts in and out for spot drilling

and drilling to size

Here they are all test fit on the crankshaft. They are a tight fit since they were drilled same size as the shaft rod, they will need a bit of lapping compound to loosen them up.

and test fit into the engine - the assembly clicked into place perfectly - very happy with that!   :cartwheel:

As I mentioned previously, I have left the shaft long on the left end so I can put on a drill chuck to spin it by hand. This will be used for lapping in the bearings with some TimeSavers compound.

That will be the next task. After that, I'll take the walls off the engine so I can get the upper shaft out to remake the indicator barrel with a left hand thread rather than the current right-hand thread. That will get the indicator dial moving in the correct directions. When re-assembling everything, I'll be able to put the front worm wheel in place over the crankshaft.

 :noidea:        :thinking:

Hmmmm, thinking about that - I think it will make sense to make the con-rods and eccentric arms before that final assembly, its much easier to test fit them when the crankshaft is out of the machine...  Lots still to go on this model: conrods, eccentric arms, pistons, valves, cylinder/valve bodies, support posts, crosshead guide plates/covers, piping.  At least at this point its almost all moving parts and looking like an engine!
 :cheers:

Offline Admiral_dk

  • Full Member
  • *****
  • Posts: 3752
  • Søften - Denmark
Re: Chris's Build of Steering Engine
« Reply #552 on: November 27, 2022, 12:50:46 PM »
Quote
and test fit into the engine - the assembly clicked into place perfectly - very happy with that!   :cartwheel:

YES  :Director:  - that feels good to make that statement, doesn't it  :whoohoo:

Great progress and I see that you came up with a better solution than what I could imagine before you showed yours  :ThumbsUp:     :cheers:

Per

Offline fumopuc

  • Full Member
  • *****
  • Posts: 3231
  • Munich, Germany, EU
Re: Chris's Build of Steering Engine
« Reply #553 on: November 27, 2022, 01:14:15 PM »
Hi Chris, last night I have tried to catch up all the postings from you and Michael about this beautiful piece of model engineering.
I am very happy also, that a piece of European engineering has found its way into the US world of model engineering.
So far, it was only me, who has done it the opposite way, by building all these beautiful American model engines designed by Doug Kelley.
Again a very special and extraordinary work, made by your elves and of course yourself.
Kind Regards
Achim

Offline cnr6400

  • Full Member
  • *****
  • Posts: 2731
Re: Chris's Build of Steering Engine
« Reply #554 on: November 27, 2022, 02:20:31 PM »
 :ThumbsUp: :ThumbsUp: :ThumbsUp: :popcorn: :popcorn: :popcorn:
The shaft and bearing assembly looks great Chris!
"I've cut that stock three times, and it's still too short!"

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal