Stephenson's Rocket

[Brian Rupnow]

This is a "trial assembly" of the welded wheels fitted to the chassis. When I get some yellow paint on those wheels, it's going to look awesome!!!

[Brian Rupnow]

Three wheels done, one to do yet. The good side which faces out away from center looks fantastic. The inside of the wheels which face towards the center are ugly as Hell. This is one of the few times I wish I had a little sandblasting cabinet. After I finish the last wheel, I will have to make a decision whether to spend a bit more time on the inside faces of the wheels with a bit of body-fill, or maybe just clean them up with my Dremel tool and leave it at that. The tig welder is perfect for making tiny welds on the ends of the 1/8" square spokes where they connect to the hub and to the outer rim.

[Brian Rupnow]

This is something I've wanted to check, but couldn't until I had the drive wheels machined and assembled. My computer shows me that I have about 1/16" clearance between the clevis on the center shaft and the outside of the wheels outer rim. The computer is like having an old friend who lies once in a while. You want to believe everything it says, but you feel a lot better after you've actually verified that it did tell the truth. Sure enough, there is clearance there. Not very much, but enough.  The lever is at its maximum travel here, and from where I show it, it only swings back in the other direction away from the wheel.

[crueby]

 

[Brian Rupnow]

This is a view of the "Belly of the Beast". I've spent the entire day reassembling, adjusting, adding a bit of clearance here and there. Right now one engine runs and one doesn't.  Tomorrow I will try and get the second engine set up to run correctly. I'm down to the point where I am just about ready to paint the wheels, but not until I have everything adjusted properly. After the wheels are painted and reinstalled, I have to fabricate a prettier air supply.

[Brian Rupnow]

TA-DA!!!--It is alive and running on both engines. It is standing on end right now, which gives me much better access to the eccentrics so that I can adjust the valve timing.
<a href="https://www.youtube.com/watch?v=IAgPIhVRkek" target="_blank">http://www.youtube.com/watch?v=IAgPIhVRkek</a>

[crueby]

Excellent!!!   

[Kim]

Looks great, Brian!
Don't you love it when they run! 

Kim

[Brian Rupnow]

Today was wheel painting day. Very nice yellow from Tremclad, same as the boiler. Now I have to figure out the pressure line plumbing for the cylinders. That is not going to be a simple thing. I have something in mind, but  have to do some cad work now to see if it's going to be possible.

[Brian Rupnow]

Things are going to get really strange in order to get air pressure into the cylinders and still have everything "look right". There is a bit of work in this, but it is almost the last work I have to do before remounting the wheels.

[Brian Rupnow]

Today I worked on the series of manifolds necessary to get air into the cylinders. This was one of the areas that wasn't pre-engineered. I wanted the airline to be attached at the back of the Rocket, under the center of where the operator stands. Since this part of the build was a "make it up as you go along" operation, it required that the operators platform and fire-box and rear stay rods had to be removed from the model to be worked on.  First, I drilled and reamed a 7/8" hole completely thru the firebox. Then I made up a 7/8" length of aluminum which fit flush from side to side. A 3/16" diameter hole was drilled full length thru this piece, and each end was counterbored for an o-ring seal, and drilled/tapped for four #4-40 socket head cap screws. A hole was cross drilled half way thru the piece on center, and threaded 3/8"-16. The piece now obscured the 1/4"-20 thread for the bolt which holds the fire-box cover in place, but with some artful head scratching and measuring, a #10-24 hole was drilled and tapped in the appropriate position to accept a #10-24 shcs. While I had everything set up in the mill to cut the 7/8" diameter holes, I also drilled and tapped one side of the fire-box for a #8-32 set screw to anchor the 7/8" aluminum round bar in position. Also, I drilled a 13/32" clearance hole up thru the operators platform and thru the bottom of the fire-box. This allowed me to use a 3/8" diameter piece of steel, threaded on one end , to screw into the threaded hole in the 7/8" cross-piece. I also drilled a 1/4" clearance hole thru the rear axle bracket, which allowed me to install a piece of 1/4" diameter steel round bar thru the bracket and into a hole prepared in the 3/8" piece of steel. Some of these holes were much easier to drill in the manifolds from each end, so after I had made a trial assembly to be sure everything fit, I liberally coated all of the connections with J.B.Weld and screwed/pushed everything together and inserted steel plugs into the open ends where I didn't want air to escape. The metal tubes which extend downward from the valve boxes on the cylinders will have a flange on the bottoms which bolt to the ends of the 7/8' round aluminum. Damn, it takes almost as long to explain what I did as it did to do it. Last job of the day was to update the drawing package  and add these new parts to the assemblies and make detail drawings of them.

[Brian Rupnow]

Today, I have had my butt thoroughly and awesomely kicked by Mr. Stephenson. The goal was to get set up for fabricating the air pressure lines feeding the steam-chests. This picture shows where I am ultimately going. It has been a worrisome and eventful day, but I have one side set up. The bent copper tube gets silver soldered to the flange. It is a "slip fit" over the barb hanging down from the steam-chest cover, and will be sealed tight with J.B. Weld.---At least that is the plan at the moment. If I'm really forced to, I can use a flexible nylon line there, but I don't really want to. By the time I'm done here, I'm going to have to repaint the fire box.

[Brian Rupnow]

Mr. Stephenson and I got on much better today. I'm not 100 percent sure right now, but I think I've almost ran out of parts to make.

[crueby]

Glad you guys are getting along again!  Looking terrific.

[Brian Rupnow]

I really have to try and find a model "driver". I need a little man 5 1/2" to 6" tall to stand on the platform. I haven't got around to checking any of the toy stores yet.