Author Topic: Another MEM Corliss - Jason's build  (Read 1716 times)

Offline JasonP

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Another MEM Corliss - Jason's build
« on: June 19, 2023, 10:44:49 PM »
As many may know I'm attempting the MEM Corliss. This is a learning experience and lots of fun and frustration as I figure out how to machine the parts. For funsies I'm posting a video I made of the latest attempt at the cylinder. This is my second attempt, the first one wasn't very good. This time I'm machining it out of 12L14 instead of 1018, which is much nicer. The last attempt I broke lots of drills and taps and finally gave up trying to fix it. I decided to start again and use what I'd learned doing the first one and see if I could get something better. I didn't decide to start videoing until after I'd started, so this picks up after I've already done some of the work. It's all handheld Iphone footage so don't get too excited. Half the time I'm repeating the operation after the fact and yes, I know that I don't show the correct use of the snap gauge....

<a href="https://www.youtube.com/watch?v=M5Iu_nY8fnc" target="_blank">http://www.youtube.com/watch?v=M5Iu_nY8fnc</a>


Offline astroud

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Re: Another MEM Corliss - Jason's build
« Reply #1 on: June 20, 2023, 09:27:01 AM »
You are not alone, I too scrapped a cylinder after most of the work was complete, I managed to mill a steam chest too deep after my depth stop slipped without me noticing.
I milled the steam chests and drilled the 4 holes for the valves before drilling the transfer ports into the cylinder to reduce the distance for the port drilling and the chance of a broken drill. Still nerve racking.
Andrew

Offline Caber

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Re: Another MEM Corliss - Jason's build
« Reply #2 on: October 29, 2023, 09:20:12 AM »
How are you getting on with this?

Offline JasonP

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Re: Another MEM Corliss - Jason's build
« Reply #3 on: January 04, 2024, 08:58:44 PM »
So it's been a while since I posted, but the holiday was a great opportunity to work on the Corliss.

https://youtube.com/shorts/9yPkp-jb3J0?feature=share

Still have a bunch of stuff to do, the big one is making the guide support.

I've tried making the disk arms 4 times and haven't managed to get them right :censored:

I've a bunch of little short vids i made, I'll post them on youtube when I get a chance.

Cheers,

Jason

Offline Dalboy

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Re: Another MEM Corliss - Jason's build
« Reply #4 on: January 06, 2024, 10:34:10 AM »
Jason this may be of interest as it just popped up on my list.

<a href="https://www.youtube.com/watch?v=i1MsGvYaMWs" target="_blank">http://www.youtube.com/watch?v=i1MsGvYaMWs</a>

Offline JasonP

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Re: Another MEM Corliss - Jason's build
« Reply #5 on: January 07, 2024, 03:33:25 PM »
That's a lovely model Corliss!

Offline steamer

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Re: Another MEM Corliss - Jason's build
« Reply #6 on: January 07, 2024, 03:42:47 PM »
That's looking great Jason!     John ( Maryak) would be very chuffed with that!

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

Offline JasonP

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Re: Another MEM Corliss - Jason's build
« Reply #7 on: February 20, 2024, 02:49:57 AM »
Quick poll of the knowledgeable.

Crankshaft to flywheel
a) Grubscrew
b) Loctite (bearing retaining compound)
c) Key (bad idea I don't have the kit to cut it).

I'm leaning to Loctite, but grubscrew is an option.

Offline crueby

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Re: Another MEM Corliss - Jason's build
« Reply #8 on: February 20, 2024, 03:04:45 AM »
D) Taper lock.




Easy to cut if you have a compound slide to  bore the hub at about 5 degrees. Very strong joint, no wobble, and it can be taken apart. I can post details if you want to try that route.


Chris

Offline JasonP

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Re: Another MEM Corliss - Jason's build
« Reply #9 on: February 20, 2024, 04:45:33 AM »
Yes please Chris

Offline Jasonb

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Re: Another MEM Corliss - Jason's build
« Reply #10 on: February 20, 2024, 06:58:10 AM »
On something as small as the MEM A grub screw would do provided you have a good close fit on the shaft and provide a flat for the screw to bear on. 1000s of Stuart engines with similar size flywheels running with just a grub screw.

Keyway is also possible and you don't have to use a broach to cut the keyway, it can be planned on the lathe.

Loctite will be a bit of a pain as you will need to get the flywheel on and off a few times during building and after test running to paint it.

Not a fan of taper lock as they seldom look anything like scale.

Offline Michael S.

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Re: Another MEM Corliss - Jason's build
« Reply #11 on: February 20, 2024, 08:06:49 AM »
I also prefer the grub screw.
When the flywheel has taken its final position, the screw leaves an imprint on the crankshaft. This mark is then drilled into the diameter of the screw.
That's a safe bet then. If there is a tight fit in the flywheel, the notch on the crankshaft can become a problem during disassembly. The flywheel can no longer be moved on the crankshaft. This can no longer happen with the drilling.

Michael

Offline crueby

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Re: Another MEM Corliss - Jason's build
« Reply #12 on: February 20, 2024, 02:07:57 PM »
For those interested, I just posted my writeup of the taper locks here:
https://www.modelenginemaker.com/index.php/topic,11770.0.html
It was done originally for Live Steam magazine, but I retain the rights to it per the authors agreement with them, so I am allowed to repost it here without copyright problems.
Just an option - there are many ways to attach the flywheel, as others have said. Here is a picture of a small taper lock that I did for my current build, on a crank disc that is just 1.75" diameter. The big thing I like about taper locks is that it does not mar the shaft, so no problems taking it apart and still getting the shaft through bearings.



Offline astroud

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Re: Another MEM Corliss - Jason's build
« Reply #13 on: February 20, 2024, 03:18:38 PM »
I used Loctite on mine, the smallest dab is sufficient making it easy to disassemble if needed

Offline Krypto

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Re: Another MEM Corliss - Jason's build
« Reply #14 on: February 20, 2024, 04:35:15 PM »
The taper lock setup certainly looks much better than a grub screw, imho. Thanks for posting that guide Chris!
My Workshop Blog:  https://doug.sdf.org/

 

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