A TRIP DOWN-UNDER
With most of the work top-side completed, it was time to flip the car upside-down (carefully) and work on some of the underside aspects of the car build and other details...even if those might NEVER see the light of day.
Rods 'n Posts: old time cars with wooden frames were known for truss rods to pull the ends of the car together and prevent middle-age "sag". While it's doubtful the model #5 and #6 will ever encounter this problem, truss rods, even if only the (2) outboard rods were installed as a nice feature.
Got on line to find 8-32 thread die cast turnbuckles. If you're going to do more work like this, best to find a source of such parts and "stock up". As has been pointed out before on Chaski...never know when the resources will no longer be available. As for tooling, if you've already got right hand taps and dies...might want to latch on to left hand taps and dies for this kind of work.
The steel hardware provided with the turnbuckles was set aside. Made my own rods with 1/8" steel wire. Made left/right hand threads accordingly. Estimated the rod lengths as close as possible. Best to make them longer than needed and trim off the excess later. Had Honest Dave TIG weld some washers on one end of each rod for mounting to the underside of the car body.
Did the best I could to scale the queen post dimensions from the magazine line drawings while maintaining proportions. Turned the post fabrication part of the project over to Dave. Needed (8) short posts for #5 and #6. As long as Dave was set up to make queen posts, had him make (8) longer queen posts for his project. Believe the posts were made with brass, sand blasted and painted when the turning was complete.
Queen posts timbers were cut and planed from white oak. The #5 combine presented another challenge...the propane tank ventilation floor screen was directly where the queen post timbers would be located. Made the appropriate cut and splices so the timbers would "bridge" the screen and steel center sill.
The queen posts were drilled and tapped during fabrication. Want to say tapped for short pieces of 10-32 thread rod. The queen post timbers were also drilled and tapped. A short 10-32 stud was used to screw the queen post onto the timber. Would tighten the queen post until the rod seats were parallel to the car edge.
Took a 4-40 stainless square nut and drilled/tapped that for 8-32 RH thread. Would use this as a turnbuckle lock nut after the installation was completed. Threaded the lock nut in place on the right hand threaded rod and then screwed the rods part way into the turnbuckle. Set the turnbuckle on the rods, centered the turnbuckle and marked the location to bend the rod ends. When satisfied with the "fit", drilled pilot holes and screwed the ends of the rods to car body. Rotated the turnbuckle to tighten the parts and screwed the lock nut against the turnbuckle. Geez...took longer to describe this than the actual work. In the end, here's how the posts, rods and turnbuckle turned out.
Pneumatics: as long as the car was upside down, this was the time to install the air brake hardware. I am aware there are those that advocate simulated triple valve type air brake systems. Can appreciate the effort that went into the design and fabrication to make working pneumatic systems like that. I've run "straight air" brakes for years for several reasons (whether people agree or not..and don't want to start a "brake" debate here): 1) simplicity, 2) cost, 3) ease of teaching newbies train brake handling and stopping distance. It's more important to be able to stop the train...than to get it going!
The #5 combine was built to carry a propane fuel tank for the loco, but also carry an air compressor module for brakes and a 12 volt battery module for compressor power and locomotive lighting. The battery module has a self contained charger built into the module.
As such, two air lines are needed. I call the 1st air line the "air reservoir". The compressor module has an air reservoir. An on-board pressure switch maintains reservoir pressure between 50 - 60 psi. The reservoir line runs under the combine, jumps over to run along the underside of the tender and then jump over to the locomotive cab. The cab has a brake lever stand and a Clippard MAR-1C linear regulator mounted under the cab floor. A cam, operated by the brake lever, will push the plunger on the linear regulator farther in as the brake handle is turned. When the brake handle is returned to "release" or off position, the regulator vents whatever air pressure was in the line. Similar operation is attained with the Clippard MAR-1 rotary regulator. The cab floor has (2) pressure gauges. One gauge displays the reservoir pressure. The other gauge displays the "brake pipe" or regulated pressure. From the pressure regulator, a 2nd air line known as the "brake pipe" runs back under the tender to the combine and any trailing cars with air brakes.
In the next photo, the (2) air lines are color-coded. The gray poly tubing line is the air reservoir and the black poly tubing is the brake pipe. During installation, had to go back and open gaps in the body bolsters and queen post timbers to pass the 1/4" poly tubing thru. Else, simply used 1/4" cable clamps to hold the poly tubing in place.
Note the Clippard quick connectors mounted to the end beam are color-coded as well. The air reservoir line uses nickel-plated connector. The brake pipe line uses the standard brass connectors. The back of the tender is similarly equipped. When I travel and have someone helping to get the train put together, it's easier to instruct them...nickel to nickel and brass to brass for the air line connections.
Another note...Clippard quick connectors are installed between the brake pipe and each truck. I'm a strong believer in serviceability. It's amazing how the poly tubing gets shorter each time you have to cut and splice it. Therefore, if the trucks need to be removed for service... disconnect the truck quick connector, pull the "R" clip that retains the truck on the king pin, lift the car end and roll the truck out (and set the car on a block). Have never regretted the extra cost for a pair of quick connectors. The poly tubing pig-tail for the quick connector on the car body is kept as short as possible. If the air line to the truck needs to be disconnected, it stays out of the way.
Have never liked the use of "X" or "T" fittings. Have enough Clippard parts on hand to make up a right angle "T" fitting alongside the center sill. This keeps the air connections centered. A small amount of slack is left to allow for truck swing.
From the other end of the car, you can see where the air reservoir line passes thru the car floor to the compressor module that would be located inside the car. The brake pipe line terminates at the quick connector plate on the other end beam. Best to secure the poly air lines as close to the center sill and as close to the floor as possible to keep the wheel flanges from contacting and rubbing a hole in the poly tubing.
Break...think I'll stop here. Next time, will cover the fuel plumbing. Carl B.