< Bogie Truck Design Change 2 >
Finally I completed modification of the bogie truck side control system that I had noticed in April. So I report here.
The photo shows current spring type side control system. I like to change it to rocker type with minimum modification.
The drawings show rocker type side control system. The magenta parts are the rockers. I started from them.
The rocker's shoulder shapes circular arc of the opposite shoe center. So I drilled the center and cut opposite shoulder in rotary table. The photo shows cutting result without clamp. After that, cut the hole in half and silver solder shoes of short round bars.
Two rockers are coupled with a round bar body. The body has an arm for link to the bolster. The body is shifted from center so as to clear bogie center pin. All of the parts are screwed on the body and silver soldered.
Pedestals for the rockers are cut from gunmetal round bar. Cut rectangular in four-jaw and cut recesses for rocker's shoes by drilling holes and sawing it in half.
Finished pedestals are screwed onto the base plate. The base plate will be hung with eight studs.
The bolster has to be remade. I made a wood pattern with Modela and requested a gunmetal casting.
Cut front and back faces and cut center bush part.
Bottom incline is 1/5. So the taper gauge for main rod wedge can be utilized again. The photo shows how to set up in 1/5 angle.
Cut inclines by end mill. There are four inclined faces at bottom. The same angle two faces are cut in a time.
After drilling holes for links, the bolster is completed.
Combine the rockers and the bolster with links and pins.
Temporarily assembled side control system.
The system was installed in the bogie truck. I utilized lubricant grease freely. Note two small band plates securing the bolster from front and back so as to avoid jumping out.
I changed bogie truck center pin type. The upper old pin was a stud type from chassis. The lower new pin is a bolt type bolted from bottom. Incidentally the bolt is a round bar with silver soldered hexagonal head.