Author Topic: Stephenson's Rocket  (Read 28557 times)

Offline gbritnell

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Re: Stephenson's Rocket
« Reply #225 on: July 06, 2020, 08:30:15 PM »
Man o man that looks great Brian. Adding the paint to it really brought it alive.
gbritnell
Talent unshared is talent wasted.

Offline Brian Rupnow

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Re: Stephenson's Rocket
« Reply #226 on: July 06, 2020, 09:16:26 PM »
Thanks George--It is really, really unusual for me to paint anything I build. I love the way this thing has turned out. I'm trying to get my steel supplier to get off their butt and get me a price on material to make the drive wheels. It means a lot to me to get a thumbs up from you.---Brian

Offline Art K

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Re: Stephenson's Rocket
« Reply #227 on: July 06, 2020, 11:23:14 PM »
Brian,
I agree with George, the Rocket looks great with it's fresh coat of paint.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Firebird

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Re: Stephenson's Rocket
« Reply #228 on: July 07, 2020, 05:14:09 PM »
Hi

Great build Brian  :ThumbsUp:

I have enjoyed following along

Cheers

Rich

Offline Brian Rupnow

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Re: Stephenson's Rocket
« Reply #229 on: July 07, 2020, 11:28:28 PM »
Today I turned seventy four. Ringo Star and I share a birthday, but he is six years older than me. Happy birthday Ringo!! I spent the entire day setting up the engines to run in the newly painted chassis. One engine started up right away with no drama. The other engine was a stubborn pig all day, and I still don't have it running. I did pick up the material for the large drive wheels today, and I'm looking forward to starting on them as soon as I get the second engine to run.

Offline crueby

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Re: Stephenson's Rocket
« Reply #230 on: July 07, 2020, 11:38:25 PM »
Happy birthday Brian!

Offline Art K

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Re: Stephenson's Rocket
« Reply #231 on: July 08, 2020, 12:01:30 AM »
Brian,
Have a great Birthday! I Hope your wife cooks your favorite meal, and also your favorite cake.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline Brian Rupnow

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Re: Stephenson's Rocket
« Reply #232 on: July 08, 2020, 12:41:37 AM »
Well she got it very close Art.--Big barbecued steak and cheesecake for desert.

Offline Brian Rupnow

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Re: Stephenson's Rocket
« Reply #233 on: July 08, 2020, 02:16:34 AM »
So, here we are kids!!! After what seemed to be an awful lot of frigging around, both engines are up and running on the model. To time these slide valve engines properly, the cylinder has to be either at full extend or full retract, and the valve control rod must be exactly at mid travel. That is not really as easy as it sounds.--A hint--put 3 setscrews at 120 degrees apart in each eccentric hub. Although that is not good practice on most hubs, if you don't do it, then when the engine is timed perfectly, the single set screw will be hidden behind something and you won't be able to access it. The engines are "lurching" a bit, but that is just a matter of timing, and can be corrected.
<a href="https://www.youtube.com/watch?v=EkLAnVPH6nE" target="_blank">http://www.youtube.com/watch?v=EkLAnVPH6nE</a>

Offline Craig DeShong

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Re: Stephenson's Rocket
« Reply #234 on: July 08, 2020, 03:49:16 AM »
Happy birthday Brian! 

The model runs and looks great too!
Craig
The destination motivates us toward excellence, the journey entertains us, and along the way we meet so many interesting people.

Offline Jasonb

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Re: Stephenson's Rocket
« Reply #235 on: July 08, 2020, 07:30:06 AM »
To time these slide valve engines properly, the cylinder has to be either at full extend or full retract, and the valve control rod must be exactly at mid travel. .............................The engines are "lurching" a bit, but that is just a matter of timing, and can be corrected.

Brian, you actually want the valve to lead the crank which will give smooth running not have it 90 degrees, try about 20deg of lead on air and 30deg if on steam, exact angle will depend on any lap that you have on the valve.

Offline Mike Bondarczuk

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Re: Stephenson's Rocket
« Reply #236 on: July 08, 2020, 08:25:49 AM »
Happy Birthday Brian  :cheers: and what a superbly designed and finished engine.
"Everything I can't find is in a totally secure place"

Offline Brian Rupnow

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Re: Stephenson's Rocket
« Reply #237 on: July 08, 2020, 08:26:45 PM »
Thank you Jason--I will try that. Now I get to see whether or not I'd make a wheelright. This piece is 5 1/2" outside diameter x 3 1/2" inside diameter x 1.8" long. It is the only piece that size in all of Barrie, and I got it for $21.50 there is sufficient material there to make two drive-wheels, and I will try and make a detailed post as the drive wheel fabrication progresses.

Offline crueby

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Re: Stephenson's Rocket
« Reply #238 on: July 08, 2020, 08:40:35 PM »
Thats gotta be a heavy chunk too!  :popcorn: :popcorn: :popcorn:

Offline Brian Rupnow

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Re: Stephenson's Rocket
« Reply #239 on: July 08, 2020, 10:40:58 PM »
I've looked at a few different ways of fabricating these large drive wheels. I really liked whats shown here, because the round holes in the hub locate the spokes radially, and the sides of the groove in which the spokes set keep the spokes all parallel.  The spokes could be loctited into the holes in the hub, and tig welded to the outer rim. The only problem is that every one of the 24 spokes would have to be set up in the 4 jaw chuck, indicated, and then turned down to 0.150" diameter in order to work. I don't mind a bit of 4 jaw set-up, but doing it repeatedly 24 times is a bit too much.


 

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