MEM Corliss finished

[astroud]

Hi
I have completed my MEM Corliss.
I set it to run clockwise looking at the valve gear side, now I see the J de Waal drawings  showing it as having a anti clockwise rotation.
Though of no consequence to a model what would be correct for a full size engine or does it depend on what it would be powering ?
Andrew

[ShopShoe]

That's very nice.

I'm glad to see that you have got it done.

Thank You for posting.

--ShopShoe

[ShopShoe]

BTW,

I notice the picture is upside down on the post, but it turns right-side-up when I click on it to enlarge it.

I've never seen that behavior before.

--ShopShoe

[jonesie]

 :ThumbsUp:andrew  that looks really nice ,you did a nice job, hope you can post a video of it running. that is funny on the pic flipping when you click on it. jim

[Jo]

Well done 

I set it to run clockwise looking at the valve gear side, now I see the J de Waal drawings  showing it as having a anti clockwise rotation.
Though of no consequence to a model what would be correct for a full size engine or does it depend on what it would be powering ?

Most engines run what is termed as "over" i.e. with the top of the flywheel running away from the cylinder by doing this the pressure on the crosshead is always downward upon the guide and into the floor.    It may not be that obvious lets try explaining a bit more: When the pressure is on the far end of the piston it pushes the rod out and the thrust of the connecting rod pushes the crosshead down. When the pressure is on the crankshaft end of the piston it is pulling the connecting rod which is now below the centre line and the weight  being below causes a force on the crosshead down   

The only reason to run an engine "Under" is if it is impossible to give the correct direction to the drive belt from an "Over" running wheel.

Jo

[cwelkie]

Very nice indeed - congratulations!

Thank you Jo for the story behind the “direction of rotation” ... it’s still early (here) and already I’ve learned something today.

[vcutajar]

Nice one Andrew.

Vince

[astroud]

Thanks for the comments.
I did a double take when I saw the image upside down, I don't know why it did that as it is correct on my computer.
The reason for the normal direction of rotation makes perfect sense thanks, I wonder why Julius showed it otherwise on his drawing.
You may notice a few changes form the MEM drawings, bent eccentric rods look wrong to me so mine is straight, consequently the crankshaft bearings are further apart. Not having hard soldering facilities or a big mill meant I made the cross head guide support, bearing pedestal and eccentric lever pivot in 3 pieces.
There is one broken 6BA tap in it and a sleeved valve bore in the cylinder where I messed up.
I will try and discover how to put up a video of it running.

Andrew

[astroud]

First time for me to put up a YouTube video, I hope it is successful <a href="https://www.youtube.com/watch?v=8wz8sBTpOVA" target="_blank">http://www.youtube.com/watch?v=8wz8sBTpOVA</a>
 

[steamer]

Awesome!   Nicely done!

Maryak would have approved immensely! 


Dave

[crueby]

Beautifully done!

[vcutajar]

Another great running MEM Corliss.  How many are there now?  I lost count.

Vince

[Larry]

Another great Corliss - Congratulations !

[Bear]

Great job.

[Kim]

Congratulations!  It runs beautiful!  And it looks beautiful too!
Kim

[Jim Nic]

A well made engine indeed, well done.
 How did you make the flywheel?
Jim

[kvom]

Beautiful runner

[astroud]

Hi All
Thank you very much for the kind comments, out of my other 2 engines, the Potty Mill engine and the Monitor it is the sweetest runner.
The flywheel was made from a billet. I doubted my ability to end up with a true running wheel by following the MEM design.
The billet was mounted on a faceplate with mounting screws positioned where the spoke cut outs would be. The rim was turned and a recess machined. The bore was drilled and then finshed to size with a boring tool. The wheel was then flipped on the faceplate and a short axle put in the bore and held in the lathe spidle with a collet, this provided location only as the wheel was again bolted to the faceplate. The second recess was machined.
The disc then went onto my BCA which you might know has a built in rotary table. A while back a contributor (and sorry I have forgotten the name) published a comprehensive step by step guide to producing a spoked flywheel which I have found excellent. Even so each time I twiddled a wheel I did a sanity check to make sure I had moved the right distance in the right direction, towards the end it became a bit nerve racking.