BenHawkins

The final task for this week was picking up the new (longer) splined shaft from the gear cutting company. We used their press to put the knuckles back on. It took around 14 tons so I was glad to have done it there as my press only manages 10.

The radiator cap just pushes onto the filler; not the most secure of fixing methods. There is meant to be a chain to stop it getting lost but this was missing. I bought a brass basin chain from an internet store. I decided it still looked a bit flimsy so soldered each link. I then fitted it to the riveted loops in the radiator and cap. We fitted the bottom tank to the radiator with a rubber gasket and sealant, then replaced the incorrect bolts in the top tank with slotted cheese head machine screws.

I bored a bar end of steel out to the right diameter, cut it and welded it to some steel strip to make the centre exhaust bracket. This clamps around a larger piece of pipe that gets brazed to the front section of the exhaust. I didn't bore the flange that fits to the manifold initially so I put it back on the lathe and bored it out to the pipe diameter. I was then able to line up the section of pipe that I crushed and split previously. At least it helped me work out what it needed to be; I have now sent a sketch off for a quote to have it bent for me.

I have used a router to trim back the ash frame to the line of the arches over the cab doorways. And finished shaping the tops to the line of the roof. It is starting to come together quite well.

In the factory photo there is no bracket for a headlamp at all (only for side and tail lights). At some point the chassis was drilled for a single headlamp. I don't plan to drill any extra holes in the chassis.

I clamped my arch pieces to the ash frame and secured them with screws from inside the cab. I then measured for the cut out in the cab side panel and cut it with a router. The top of the arch piece was trimmed to the roof radius with a hand plane and the holes for the coach bolts were drilled through. I need to trim the ash frame back so it does not protrude below the arch but that can wait until the weather improves; I can then use the router outside and make less mess in the garage.

I had to go to the west coast of America for a week so I have lost some evenings and a weekend and that has slowed progress a bit. The jet lag seems to have led to a reduced number of photos! I failed to take any photos of refitting the flywheel. The radiator core was in the way so I decided we should put it back together again. We started by removing the original fibre gasket. Over the top of the Devcon metal putty I painted another sealant for coarse porosity in castings. The new gasket was cut from 3mm rubber. Plenty of gasket sealant was used for the sealing faces. I had applied the sealant before realising the bolts I had were the wrong length; I will need to replace them to remove the three washers fitted to each one. As a result I decided to leave the lower casting for a later date.

I bought a bent piece of pipe to make the exhaust but when looking at the run over Christmas realised it needed an additional bend. I heated it up and added the bend in approximately the right place. Unfortunately I buckled it slightly and also tore a small hole in the outer edge of the bend. I might continue to fit this and then make a drawing of it to get another one made properly!

I have purchased a new woodworking tool, a flexible router guide. I had printed some curves from DraftSight so I could use them to make a template for the planks that fit over the cab doorways. The finished template. I used the template to mark out the profile onto some mahogany, roughly cut it to shape with a jigsaw then clamped the template to the mahogany. Then used the router to get the exact shape.

Thanks for the comments on the aluminium castings; I decided to proceed with the aluminium putty. I painted the outside of the header tank with alloy wheel paint then brush painted the nameplate. We gave the core another clean and painted it with an aerosol can of radiator black. The side castings were painted to match the header tank and refitted.

The holes were then located using a stub drill in the milling machine before drilling through in the pillar drill. The flanges were then tried in position. The exhaust pipe route looks like it will be a bit of a challenge but that fun will have to wait until another day.

When the balls were originally fitted the brass ring was then indented at each opening to prevent the balls from falling out. I thought I might have to do the same after fitting the new balls but actually the cages appeared to elastically deform and just close up after then balls were fitted so the ball stay in place on their own. Best wishes for the new year to all the projects!

Some time ago I removed the broken flange from the end of the exhaust manifold and had a new blank cast. I machined diameters and then cut the screw thread. The Aster Engineering catalogue usefully informed me that the thread needed to be 2-1/8" x 11tpi I had to machine the thread deeper than expected before it would fit into the manifold. Actually it seems closer to 1-3/8" BSP I then started machining the mating flange.

The balls were then easily punched out of the cage. The balls were then replaced with new ones following the same procedure.

Although the ball bearing tracks for the thrust race are in good condition the balls themselves were very rusty. I decided to remove them from the bronze cage. They are 1/2" so I used a 1/2" ball nose cutter to make a punch with the appropriate radius. And filed a slot in a piece of tube to support the cage.

The glamorous assistant helped me to lift the flywheel onto the rotary table I had fitted to the milling machine. A dial gauge was used to make sure it was coaxial with the rotary table before bolting it down. I tilted the milling head to 10 degrees and fitted an end mill to allow me to reduce the diameter of the central boss by around 0.1". I then returned the milling head to a vertical position so I could machine a radius will a ball nose cutter. Which means the clutch hub parts now have clearance and can spin as they should.

With the cab sides clamped in place is does start to feel quite complete but there is still a lot of woodwork and painting to do. I have also been finishing off a few of the smaller jobs such as bolting things up and fitting the second steering box bracket.

The large diameter of the flywheel means it is too big to fit in my press. I am starting to see a common theme here so if I can find the space perhaps I should invest in a bigger (both capacity and tonnage) press. Anyway, the solution for fitting the centre bearing was to machine some scrap metal so I could use M16 threaded rod, nuts and spanners to force the bearing into the bore. That all went to plan and felt like I had sufficient interference between the two parts. But unfortunately I seem to have messed up a bit on the clearance between the taper in the casting and the ball thrust race as it locks up on the cast iron before the threaded collar is fully engaged. When I am feeling strong (and probably with the help of the glamorous assistant) I will need to lift the flywheel onto the rotary table and mill away some of the material.

We went away for much of Christmas but I did manage to clamp the one cab side in position before leaving and router the front edge to follow the line of the ash frame. I then repeated the procedure to make the other side. And by the time we were back from the Christmas break the paint was dry on the final arched panel for the back of the cab so it could be fitted.

Thanks for the comments on MIG welding aluminium; I was using pure argon but did not purge the system through so the first couple of arcs were very sooty. I had just been wondering if I could get away without the spool gun. My MIG power source is pretty basic and does not have a power supply for the spool gun. I could almost certainly rig up an external circuit to drive it all though. Having given up on welding these castings I had a local impregnation company use their sealants on them and also ordered some Devcon aluminium putty so I can fill a few of the craters.

I clamped the board in place so I could mark the lines for cutting. After trimming the board with a saw I roughly cut the window opening with a jigsaw. Then screwed the frame on and used it as a guide to finish the opening with a router.

I decided to turn my attention to the sides of the cab. My mahogany boards do not have straight edges so my first task was to find a straight piece of timber and clamp it to one side. Then use the router to follow the straight line; moving the clamps out the way as I moved down the length of the board. Using the 3-4-5 rule I was able to draw a line at 90 degrees to the router side. I cut close to the line with a saw then clamped a piece of timber on and straightened it up with the router.

With the final board for the back of the cab in place I drew on the curve of the roof. Then cut it out with a jigsaw. The laser cut steel template for the roof was used again with a router to tidy up the line. Then finally put the board back in place and cut the radius on the interface between the two boards.

I do think MIG could work with the right equipment and if the aluminium could be cleaned sufficiently. It might also help to have a brass heat sink on the under side to avoid the risk of burning through where the material if thin. I have a few sample plates of cast aluminium (much cleaner than my radiator castings) and gave it a bit of a go. The main problem was actually wire feed; the 0.8mm wire has very poor column strength and would birds-nest in the drive whenever I tried to weld. I am sure there are a number of things that could be done to improve this; including but not limited to: PTFE wire liner Increasing wire diameter to 1mm or 1.2mm Modifying the front wire guide to reduce the unsupported length. As for covering up the threaded repairs I was thinking about painting the whole radiator with alloy wheel paint. It seemed to look OK on the gearbox.

Thanks for finding those. However I think they are both zinc coated steel rather than a sheet of pure zinc. Zinc is a soft metal and easy to form to the shape of the roof.