I have started assembly of my MDM F-7 diesel. Since I do not own a mill or lathe I chose to buy a machined kit. I have to drill all the holes, tap a number of them for bolts and fasteners, and assemble the brake rigging for this engine.
I started with the trucks. The photos show the pieces drilled and tapped and a temporary set up with the wheels. All this will have to come back apart to set up the traction motors and brake rigging but it is starting to come together. The machined parts are extremely well done and so far everything is fitting as it is supposed to.
02 setting up truck frames with bolster by Ray Grosser, on Flickr The frames are set up with a temporary clamp in the form of all thread through the holes in the frame. These clamp the end frames and bolster in place so the holes can be transferred to the frames with transfer punches.
The brake rigging and traction motors are next and I expect the brake rigging to be the most time consuming as pieces have to be silve soldered together and that is always a long time work item for me at least.
I have the trucks ready for the last bits of brake rigging--some parts were back ordered--but they are ready for the F-7 body and frame when those parts arrive.
This has been a very enjoyable build for me--well most of the time. I had a problem that required that I take a traction motor and gear box back apart and getting the roller bearings off the axle proved to be a most trying event. It was finally managed and if they ever have to come off again, the bearings are not going to be so difficult get off. Emory cloth works so well......
12 trucks are nearing completion by Ray Grosser, on Flickr The trucks are magnificent. The working air brakes and the traction motors are very well defined and make these trucks absolutely wonderful. Very professional engineering on these trucks.
I finished the trucks and brake rigging today and started on the chassis.
The photos show the floor and frame sitting on the trucks at the correct location and the fuel and battery tanks are sitting on some 2X to get an idea of where they will finish up. The skirts are finished and will be permanently installed once the frame and floor are welded together.
All the holes are drilled and tapped where required in the floor. The floor is a magnificent piece of workmanship, laser cut edges and the larger holes in 10 gauge thick steel. This would have been impossible for me with hand tools--I had a tough enough time making the cuts in the skirts with a drill and saw then finishing up with a hand sander and grinder.
15 brakes finished by Ray Grosser, on Flickr The brakes are finished and installed. The brakes are also adjusted as per the instructions and ready to run when air is applied. Holding one cylinder open will stop a pair of wheels with no load on the trucks so I am very confident that these will hold the engine when stopped.
19 fitting fuel and battery tanks by Ray Grosser, on Flickr Fuel and battery tanks sitting on some 2 X material to get an idea of how this is going to look. The skirts will be installed after the chassis is welded together and the tanks installed.
The engine is already too heavy for the two of us to pick up with the trucks on so once the parts on the bottom are installed and the king pins pinned the whole build will have to be on the bench with the track. I knew it was going to be heavy but it does surprise me how quickly it has 'Bulked UP' with just the chassis and trucks.
I have the engine together, The sides and roof are on and the cab has the number boards installed with the light boxes behind.
I had my first wreck today. I was pushing it out of the barn on to the bow string truss and I managed to run the leading truck off the rails. MAN is this thing heavy. I am going to have to build a rerail outfit once the trucks have the pins in as there will be no way in the world to right this thing once the batteries are installed.
I also had to have a 11/16 hole in the nose to install the class light holders. I did not want to buy yet another large bit that would be used only ONCE so I predrilled the holes with a 1/2 inch bit then I ground off an old 3/4 inch fly bit with a taper on the drilling surfaces. This works on aluminum and wood.
25 roof is on by Ray Grosser, on Flickr Engine with the roof on, number boards installed and the light boxes are in. I have some work to do on the cab before I can put the pilot on permanently.
The battens are being installed as well as the radiator grilles. I have the headlight in the door and the figure 8 Mars light in the upper light housing. A lot of work remains before we can paint but it is coming along.