Author Topic: JC attempts the MEM Corliss  (Read 3131 times)

Offline JCvdW

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JC attempts the MEM Corliss
« on: October 29, 2020, 09:47:59 AM »
Being inspired by the MEM Corliss steam engine build threads of Arnold (http://www.modelenginemaker.com/index.php/topic,1333.0.html), Vince (http://www.modelenginemaker.com/index.php/topic,1526.0.html),  and others, I decided to give it a go.

I will be using the 24mm to 1 inch metric plans, found here: http://www.modelenginemaker.com/index.php/topic,1285.60.html

Thanks to everyone for all the relevant information available on this forum.

Being a novice, and this my first steam engine, this may end up being a bridge too far ...

I decided to start with the flywheel, and to construct it from separate parts for the rim, spokes and hub.
I ordered some hollow bar for the outer and inner rim. The closest sizes I could find were 180 x 150 mm and 170 x 140 mm.



The Myford Super 7 has a capacity of 178 mm, so I had the outer rim machined down to 176 mm by a local engineering shop. The outside had a very good finish, which I hoped I could use as is. I clocked it in as best I could on the four yaw chuck and started boring out all the excess material.





As the rim got closer to size, I noticed that the material had warped and that the outside was not running true anymore. By now the rim could fit over the chuck, so I remounted it and turned the outside to be circular again, removing 50 micron at a time. The tool just reaching the width of the rim.





Now to bore the inside to final dimension. I tried to grip the rim on the outside, but found that gripping on the inside results in less distortion of the rim. The best I could clock it to was about 100 micron, with as light a grip as possible. I bored out the inside from both sides taking off 50 micron at a time. I left the inside diameter on one side about 100 micron smaller to create a reference edge for the inner rim to fit against, as suggested by Arnold.


So after many more hours than I expected at the start, the outside rim is complete. Quite pleased with the final result.





Now for the hub and the inner rim. I already made an indexing plate that fits on the outside of the lathe spindle, to use when drilling the spoke holes.


« Last Edit: October 31, 2020, 08:29:48 AM by JCvdW »

Offline Ramon

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Re: JC attempts the MEM Corliss
« Reply #1 on: October 29, 2020, 11:15:54 AM »
Hi JC,
as someone just coming to the end of a Corliss build here's to wishing you well with yours. The MEM design is a nice project and a fine runner - Good luck with your endeavors :ThumbsUp:

Regards - Ramon aka 'Tug'
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline JCvdW

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Re: JC attempts the MEM Corliss
« Reply #2 on: October 30, 2020, 08:21:12 AM »
Hi JC,
as someone just coming to the end of a Corliss build here's to wishing you well with yours. The MEM design is a nice project and a fine runner - Good luck with your endeavors :ThumbsUp:

Regards - Ramon aka 'Tug'

Hi Tug

Thank you very much. I had a quick look at the video of your tandem Corliss. Beautiful! Well done! Workmanship that I can only aspire to!

Offline vcutajar

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Re: JC attempts the MEM Corliss
« Reply #3 on: October 30, 2020, 08:33:47 AM »
Good luck JC.  I am sure you will enjoy the build.  Pulling up a chair and some popcorn.

Vince

Offline JCvdW

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Re: JC attempts the MEM Corliss
« Reply #4 on: October 30, 2020, 08:59:38 AM »
Started on the hub. Mounted my hand drill on the cross slide to drill the spoke holes. Clocked it in to be perpendicular to the hub.



Setting the height of the drill, using an old drill bit with tip ground to a point.



Tapping the eight M6 spoke holes with a spring loaded tap holder in the chuck.



All spoke holes done. I took Arnold's idea and also drilled and tapped M4 holes for two grub screws to secure the flywheel to the crankshaft. Shaft hole drilled 1mm undersize, to be accurately bored later once the flywheel is assembled.



Hub complete.

« Last Edit: October 31, 2020, 08:32:38 AM by JCvdW »

Offline JCvdW

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Re: JC attempts the MEM Corliss
« Reply #5 on: October 30, 2020, 09:01:36 AM »
Good luck JC.  I am sure you will enjoy the build.  Pulling up a chair and some popcorn.

Vince

Thank you Vince. You are one of the reasons why I decided to give this a go.  :D

Online Kim

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Re: JC attempts the MEM Corliss
« Reply #6 on: October 30, 2020, 08:01:36 PM »
Hmm... JC, for some reason I'm not seeing your pictures.  Is anyone else having this problem? Or is it something specific on my end?

Kim

Offline crueby

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Re: JC attempts the MEM Corliss
« Reply #7 on: October 30, 2020, 08:22:49 PM »
Hmm... JC, for some reason I'm not seeing your pictures.  Is anyone else having this problem? Or is it something specific on my end?

Kim
Not seeing the pictures here either.   :(

Offline vcutajar

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Re: JC attempts the MEM Corliss
« Reply #8 on: October 30, 2020, 09:16:24 PM »
The photos were visible this morning but not now.

Vince

Offline Ramon

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Re: JC attempts the MEM Corliss
« Reply #9 on: October 30, 2020, 10:06:46 PM »
Haven't seen any images so far - logged in or out  :(

Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Online Kim

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Re: JC attempts the MEM Corliss
« Reply #10 on: October 30, 2020, 11:00:03 PM »
Hi JC,
Sorry about the photo problems :(

I'm betting that it's a permissions issue with wherever you have them hosted.  When you upload the pictures, you're logged in, so you can access them and see them in your posts. But nobody else is logged into your account, so we can't see them.

There's probably a way to change the permissions on the photos to allow other people access.  I don't know what service you're using, so I can't give you more specific info.  But I'm guessing if you poke around in permissions you'll come up with something.

Good luck!
Kim

Offline JCvdW

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Re: JC attempts the MEM Corliss
« Reply #11 on: October 31, 2020, 08:39:55 AM »
Kim & Tug, thanks for the feedback re the photos.

Turns out that the photo links I used were not permanent, and as far as I can tell, permanent links are not available for ICloud images. I am now using Imgur to host the images, and direct permanent links to the images are immediately shown.

Offline Ramon

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Re: JC attempts the MEM Corliss
« Reply #12 on: October 31, 2020, 10:40:38 AM »
That's much better JC - good photos too. Looks like you've made a good start  :ThumbsUp:

Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Online Kim

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Re: JC attempts the MEM Corliss
« Reply #13 on: October 31, 2020, 04:32:55 PM »
Thanks JC,

Yes, I see your pictures now!  Thanks for taking the time to re-post them.

Looks like you're making good progress on your flywheel!
Kim

Offline Johnmcc69

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Re: JC attempts the MEM Corliss
« Reply #14 on: November 01, 2020, 01:32:40 AM »
 :ThumbsUp:
 Nice job! I especially like the cross-drilling set up.
 :popcorn:
 John