Hand Pump Check Valve, Injector Steam Valve, Union Nuts, and Cones As I mentioned in my prior post, I am missing two pages of the article about the hand-pump check valve, injector steam valve, union nuts and cones. The page I do have does however show the drawings for these and there is a bit of text on the page as well so, with a bit of luck I can get these parts done correctly. I started with the hand-pump check valve and that went together fairly well, I did have to make a few calls on some placement dimensions for the union nipple but I think it should be fine. Figure 1 shows the check valve and Figure 2 shows the check valve interior. Figure 1: Hand Pump Check Valve.
Figure 2: Section View, Hand Pump Check Valve. The injector steam valve seemed to go together well too, though I did change how the knob attached to the valve spindle. Instead of smashing a 1/8 square piece of silver steel though both the knob and the spindle hole to hold them together; I cut a slot in the top of the valve spindle 1/16 inch wide and 1/16 inch deep and then tapped a hole for a 2-56 thread about a ¼ inch into the spindle from there. Then I made a protrusion on the bottom of the knob to fit that slot, and then drove it home with a 2-56 machine screw recessed in the top of the knob. If one ever needs to service the spindle for any reason it can be done easily now without having to remove the valve from the back head. Figure 3 shows the injector steam valve assembly and figure 4 shows the cross section of the assembly.
Figure 3: Injector steam valve assembly. Figure 4: Cross section of Injector Steam Valve assembly. After getting these two valves done it was now time to start on the union nuts. The union nuts are very straightforward to make but, there is more I need to add to the union nut to accomplish the task of routing the piping. SolidWorks has another feature called routing. Routing lets you route pipes and electrical wires and probably more if one were inclined to build a separate library, very easily within the program but you need to
define connection points and a routing point on your connector. Therefore, to use the routing feature all I have to do is to define those points within the union nut and I should be good to go. This is accomplished very easily in the routing tab and when clicked will give a fly out and under that you can go to routing tools and under that there is a button to create connection points called the routing wizard. Figure 5 shows the union nut and the connection point I applied to the union nut. Figure 5: union nut showing connection point for routing. Inside the connection point there are other parameters you can set such as a stub length, I made mine 1/16 inch. You can also specify the type of tube you want to use, in my case, I chose 0.125 inch tubing with a 0.010 wall and then when you set your route you can specify your material, and again in my case I used copper. Figure 6 shows the partial routing of tubing from the injector steam valve to the whistle turret and from the whistle turret to the blower valve.
Figure 6: Tube routing for blower valve and injector steam valve. With the connection point set in the compression fitting all I had to do was to start the route from the union nut connection point and then just drag the line straight up from the ISV, then add another line 90 degrees from that and then add another line back toward the union nut of the turret. After that, I added the connection point of the Turret fitting to the route, drug the line a little, and then merge the two lines. I made sure all my lines were in the x, y, z, axis and I was done. Very simple and perfectly lined up with the union nuts, so there is no undo stress. Next came the pressure gauge, but after an uneventful search online for a ¾ inch model, I had to make my own. It is very plain and simple but it also gets the point across. I routed the tubing as LBSC describes with a swan neck. Figure 7 shows the result. This may need to be moved a little more to the inside once the cab is installed, but that should not be a big deal. I am starting to run low on memory now with the boiler assembly. It seems all I do is save and rebuild. If things get worse I shall have to come up with an alternative plan for the routing, hopefully I can just suppress some of the other sub-assemblies to make a little room or add components to other sub-assemblies and bring them in lightweight. Next will be the water gauge, water level test valve and the boiler blow down valve.
Figure 7: Pressure gauge in place with swan necked tubing installed.