Continuing with the chassis sub-frame shenanigans, there were still a couple of unresolved issues with the gearbox to attend to.
While the machinery had turned out to be a remarkably good fit, it was, of course not actually designed for a model locomotive! The size of the installed gear left very little clearance below and between the wheels that was only just about tolerable for working over the plain, "indoor" plastic track, but a potential nightmare was in prospect with the proposed points and crossings, let alone a greater risk of contact with lumps of dislodged ballast, etc., likely to be encountered in the big, wide outside world.
There was one particular point of concern, and here is a pic to demonstrate:
The box is shown upside down on the bench, with the problematic bottom section uppermost! There are three fixing points moulded into the alloy casing, two equally spaced above and below, and a central one at the front, directly beneath the motor mount. On the original wheelchair arrangement, the box was attached to a battery tray framework only by a full length bolt running through that plain hole in the forward position, and the four, hex drive socket cap screws on the cover plate. The two upper and lower holes, that were incidentally M6 threaded, served no obvious purpose! I have found that one of the latter was perfectly placed for my own requirement, and you can see a machine screw fitted therein. It was the presence of the large, wide, unused lug that was causing all the consternation. I just wanted to be able to cut and file the so-and-so orf !!
The great fear was that in doing so, I might end up fatally weakening the casing - and end up ruining an item that might then cost a small fortune to replace ? I was also reticent about investigation by opening up the cover in what is otherwise a securely sealed unit, having visions of accidentally damaging the thin gasket, (not listed as a spare part by the manufacturer) losing some of the unidentifiable lubricant or perhaps even dislodging and dropping some form of spring clip down amongst the workings? After fruitless searches for any diagrams, or anyone with prior knowledge, I finally decided to act, and with some trepidation, gently removed the cover and peered inside.
I needn't have worried ! the casing walls were really nice, thick and perfectly even...
So, whoopee!
Still low I know, but that will do now!
The last issue that needed sorting was working out the best method of locking the driving wheel bosses to the axles. The bodged, plumbing fittings provided a nice, snug, push fit - but have to remain readily removable in order to gain access to the chassis fitting screws. Clearances are awfully tight between the back of the wheels and the frames, so working out whether to tap for a pair of fiddly little grub screws, or just go for simple split pins? Whichever decided upon, the hub bosses would have to be dismantled and taken out again in order to get any size of drill bit down so close to the wheel backs.
Once again, regretting the utter foolishness, and now paying the price of earlier haste ?!
I decided that stout split pins were indeed the preferred option, allowing for less meat removal and the smaller holes required. Another perceived benefit with the pins is that they would be unlikely to shake loose and drop out unseen during service, as grub screws can occasionally do.
By the way, now that the bosses are complete and have been reinstalled in the wheels for the
final time, they, and the unsupported ends of the spokes can be fully sealed and set solid with resin - at leisure now, or as and when the opportunity arises.
Slipping in and bending back the pins is still a bit of an awkward exercise, but a pair of long nosed pliers, plus a carefully planned system, does the trick well enough!
Knowing that all the lovely looking, shiny stuff was about to be buried away, almost invisibly deep within the machine for, hopefully, many moons to come prompted me to take a few snaps, just for the record...
I had originally thought that an attempt to disguise the motor and gears with paint was entirely appropriate, but strangely, I now find myself respecting it's honesty - after all, it is what it is, and I've grown to rather like it like that!
And so, at long last...
Somewhat overdue, but now all belted, bolted and braced in place !!
Now for a sturdy battery tray to get the power to this lot...
Pete.
.
