There hasn't been a great deal to report here recently. It's not that I haven't been doing anything, just that a good deal of it has been kit assembly or repeat builds.
There is one job that I did started shortly after the 2mm Expo that I thought would benefit from a few words here. We were a bit more relaxed at the Expo with mixing and matching locos to different trains. At one point this ad libbing caused us to come unstuck. My Hymek was moved from its usual local passenger turn and put onto the mineral train. It arrived smoothly into the loop and then came to a sudden and mysterious halt. A little investigation revealed the cause - it was too high to go underneath the 3 doll bracket signal that had been installed just before Railex.
The signal had been checked for clearance with various vehicles, but clearly not the Hymek. The fact that Dapol Hymeks are, well, too tall is pretty well known and Jerry Clifford has written a few words about how he improved one of his examples. I'd been intending to do something similar to mine for a long time but had never actually got around to it. I had no intention of modifying the signal, so the Hymek had to get lower.
I read Jerry's description of how he did it. If memory serves, he said that he took out the PCB and also filed the bottom of the cab front panels to allow it to sit lower on the buffer beams. I started to strip my own loco down to see for myself what was needed to make it lower… The PCB came out and the motor wires were soldered to the pickups (see photos). Rather than start filing the body away, I just removed the buffer beams temporarily... No joy.
I started to look at what was still propping the body up. I tried taking a couple of the engine bay windows out but that didn't help either. Some investigation with squashing lumps of Blu Tack between the top of the chassis and the body proved that there was loads of headroom over the chassis. After a good deal of rocking the body to see where it was being supported I found that it was the rear of the cab door handrail recesses. These stick out inside the body and their bottoms rest on the 'ledges' at either end of the chassis.
I cleaned up the back of the handrail wire and chamfered the bottom edge of the plastic that surrounded it. I also made a chamfer on the top edge of the chassis (see the picture) to allow the handrail recesses to sit lower down. Success!. At the next group meeting the loco was tested under the bracket signal and it passed with room to spare.
Having figured out the answer I then put the whole thing down and worked on other things for a couple of months.
Now we have the Aldershot show this weekend, I thought it was about time that the Hymek went back together. There was still one job remaining though - I hadn't done anything about the buffer beams (other than removing them).
My answer for the buffer beams is a bit different to Jerry's. I wanted to fix the buffer beam to the body rather than having it glued to the chassis and then modify the chassis to let the whole lot sit lower down. I first used a sharpened screwdriver as a chisel/crowbar to undo the Dapol glued joints and detach the buffer beam from the lighting surround and PCB. The coupling hook also had to go otherwise it would foul the DG coupling. The photo below shows the buffer beam stripped into its component parts and also how Dapol intended it to fit onto the chassis.
I did a little bit of filing to the bottom edge of the cab front but only enough to allow the buffer beam to sit snugly where it should. The two central 'lugs' were cut off the buffer beam. The buffer beam was then glued to the body with Formula 560 Canopy Glue (this is my default glue for lots of jobs now), adjusted for the correct alignment and then left to dry before adding more glue to strengthen the job.
Attaching the buffer beam to the body now means that you can't drop the body onto the chassis. There are two answers to this. My first answer was (after masking the moving parts of the chassis) to file away a rectangular chunk from the front corner of the chassis - see the shiny parts of the chassis in the photo below.
While doing the second corner and congratulating myself on how careful I was being not to break the brittle Mazak chassis moulding… it snapped. So… method 1 is to be more careful than I was so that you don't snap off the end of the chassis. I then convinced myself that I had brilliantly invented method 2 and it was the better way because it avoided the risk of getting metal filings into the mechanism completely. I took some chunky wire cutters and cut off the opposite 'ledge' that I had managed to file without snapping. This also removes the need to file the chamfers to allow the cab handrail recesses to sit lower down. The disadvantage of this method is that the height control for the body moves elsewhere and is less easy to adjust. I think it is now the engine bay glazing but I'm not 100% sure. A small amount was also shaved from the bottom of the buffer beams to ensure that the body was not resting on the top of the DG coupling. Naturally it will also make it more difficult to re-fit the lighting unit if I ever decide to do that.
The stats - before I started I measured the height as 28.5mm. The correct height should be 12.88 ft which scales to 26.55mm in 'N' scale. After all of the surgery so far it is now down to 27.25mm. Here's how it looks now.
Incidentally, for the benefit of those DCC types… I think that there is probably enough room between the chassis and the body to leave the PCB in place. I now have some wires in the way though so I have not actually tried it.
This is not the finished article yet but its appearance is much improved and I think it will be turning a wheel at the Aldershot show in its current state. If my theory about the engine bay windows is correct then it might be possible to lose another 0.5mm or so but I am undecided about whether that's a good idea. In any case it will involve taking out all of the windows so is definitely a job for another day. Once I'm happy that no further surgery is required then I might finally get around to weathering it.
Edit: here's the front(ish) photo that Jerry asked for. Shows up the less than perfect paintwork around the windscreens nicely doesn't it?
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