Author Topic: Tiny triple expansion steam engine  (Read 1308 times)

Offline gbritnell

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Re: Tiny triple expansion steam engine
« Reply #15 on: September 10, 2019, 05:03:53 PM »
The upper heads are finished. Builders seem to have one particular job or another that they don't like, mine is drilling scores of holes. I doesn't matter the size I just don't like drilling a lot of holes. I have the steam chests almost done, they just need the gland boss on the bottom shaped. The steam chest covers are also finished. I added a raised boss on the covers to give them a little character.
gbritnell
Talent unshared is talent wasted.

Offline steamer

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Re: Tiny triple expansion steam engine
« Reply #16 on: September 10, 2019, 05:59:12 PM »
Looks awesome George!   

 :lolb:  I have a full set of drawings for one of the main engines from the USS Ohio  BB12.    10000 HP 4 cylinder triple expansion.     The top HP cylinder head had (57) 1 3/8 studs holding it on....and that was just the top cylinder head....many more for the receiver connection, lower cylinder head, and frame connections.....I can't imagine drilling holes on that one......

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline stevehuckss396

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Re: Tiny triple expansion steam engine
« Reply #17 on: September 10, 2019, 07:02:44 PM »
I feel your pain George.  I just recently made a single piece with over 150 holes and all but nine were tapped.

Engine looks nice.
Do not be like the cat who wanted a fish but was afraid to get his paws wet.

Offline gbritnell

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Re: Tiny triple expansion steam engine
« Reply #18 on: September 11, 2019, 05:13:45 PM »
I turned up the lower heads last evening but wasn't in the mood for more drilling so I started on the crosshead guide bar. As is normally the case for parts like this I cut it into a piece of bar stock then use a slitting saw to remove it. All the holes were drilled for the posts and corner radii then the outside radii and around each post hole were stepped off. The part was then separated.
I use an ink marker to highlight the low spots where the cutter mark is then file the high spots until everything blends out.
When everything was filed and finished I set it back up to drill for the crosshead guide mounting holes. The part was then test fitted to the engine.
gbritnell
Talent unshared is talent wasted.

Online b.lindsey

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Re: Tiny triple expansion steam engine
« Reply #19 on: September 11, 2019, 05:58:09 PM »
Awesome as always George. Another little beautyto watch come to life.

Bill

Online crueby

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Re: Tiny triple expansion steam engine
« Reply #20 on: September 11, 2019, 06:21:06 PM »
Watching along, amazing parts....

Online Craig DeShong

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Re: Tiny triple expansion steam engine
« Reply #21 on: September 13, 2019, 01:34:43 PM »
Following along with the rest of the crowd.  Pretty work.
Craig

Offline fumopuc

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Re: Tiny triple expansion steam engine
« Reply #22 on: September 15, 2019, 07:29:26 AM »
Hi George, nice to see you back in steam.
Kind Regards
Achim

Offline gbritnell

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Re: Tiny triple expansion steam engine
« Reply #23 on: September 18, 2019, 11:47:09 PM »
I'm making good progress on the engine. I have all the machining finished on the lower heads. The crosshead guide plates are done. The connecting rods are started. For the rods I mill up a piece of stock to size, in this case it's .250 x .400. I leave it long for subsequent set-ups. I stand the stock up vertically in the vise using a square, mill the top edge flat, drill and counter drill for the rod bolts then using a slitting saw, cut the cap off. The faces are lightly filed then the cap is bolted on. The part is put back in the vise and the crank throw hole (.156 dia.) is drilled and reamed along with the wrist pin hole (0-80)
The main bearings have all been made and mounted. Only one had to be split for an inside journal. Being that the crank is split all the other bearings just slide in place.
gbritnell
Talent unshared is talent wasted.

Online b.lindsey

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Re: Tiny triple expansion steam engine
« Reply #24 on: September 19, 2019, 12:13:02 AM »
Great looking parts George. Seems like this one has come together very fast!!

Bill

Offline Dave Otto

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Re: Tiny triple expansion steam engine
« Reply #25 on: September 19, 2019, 01:23:51 AM »
Amazing work George!
Enjoying this one; not that I didn't enjoy all the others too. :)

Dave

Online crueby

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Re: Tiny triple expansion steam engine
« Reply #26 on: September 19, 2019, 02:16:40 AM »
More stunning parts. What do you do for the finish on the brass parts, sanded, polished?   :popcorn: :popcorn: :popcorn:

Offline Tonyr

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Re: Tiny triple expansion steam engine
« Reply #27 on: September 19, 2019, 05:14:41 PM »
Not only is it impressive work, but the progress is very fast.
How do you find the time.

Tony

Offline gbritnell

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Re: Tiny triple expansion steam engine
« Reply #28 on: September 19, 2019, 07:32:21 PM »
Hi Chris,
I just sand with real fine emery cloth, around 400 grit that has already had the tooth worn off it.
Hi Tony,
Well the fact is I'm retired so I can spend a lot of time at the machine.
gbritnell
Talent unshared is talent wasted.

Online Craig DeShong

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Re: Tiny triple expansion steam engine
« Reply #29 on: Today at 12:50:28 AM »
Hi George.  I love to follow your projects.  Great work on this one too.  How do you work on stuff so small? 
Craig