Detailing of the drive units - All sorts of handrails

Handgrips of the hatches

Push the steel in, drawing the wire with it. Gently tap it with a nylon hammer (or a piece of wood, not a heavy steel hammer).

And five minutes later I have eight identical grips.

One final photo of the lubricators and handgrips with my thumb to show how small this all is.

In hindsight I think the handgrips are too low on the covers. If you look closely on the photos, you can see they are clearly higher above the footplate. But I am not going to change this anymore.

Handgrips below the buffers

I first marked the line UNDER the birffer beam to indicate where to drill. I then carefully drilled four 0.3 mm holes.

Note that the etch provided holes on either side of the buffers in the FRONT of the buffer beam. But the photos clearly demonstrate the grips come from under the beam and are not symmetrically  located around the buffers. Hence I made my own holes.

(Click the photo to enlarge)

After soldering the handgrips where bent forward under an angle of approximately 45 degrees.

At the step in side of the water tank

The handgrips were soldered from the inside. Neat innit?

Guardrails

At an early stage in the detailing process I already did some preparations on how to make the guardrails.

Note: those with keen eyes will notice that the vertical posts of the handrail thicken just below the halfway point. I noticed this but decided not to replicate it. You have to draw the line somewhere.

Next question was how to solder them in the running board. The answer was hidden in the prototype. The guard rail had a kind of lug at the bottom that was bolted to the running board.

However, soldering to the running board is not an option. These railings are located in a vulnerable spot and could easily be damaged at an unfortunate event. Therefore, they must be easily removable. I will secure them lightly from the underside with epoxy adhesive. If something goes wrong, the railing can be easily detached by heating the adhesive.

LTM 51 in the cutting near Gulpen

So I made the aforementioned lugs on my Unimat lathe. Admittedly they are tiny

Where the posts meet the horizontal handrails there is a sort of knob on the prototype. I needed to mimick that. Simply butting them and then soldering them together will not result in a strong bond.

So I experimented with the connection of the guard rail poles and the horizontal bar. I filed the end of the vertical bar to a D-shape, only 0.25 mm thick. I annealed it to make the metal soft. As the material is very thin annealing only takes a few seconds. Be gentle. Then I bent the D-shaped end 90 degrees outward, put the horizontal bar in a vise and curled the D-shaped end of the vertical bar around it. A touch of the soldering iron fixed it in place.

I was not happy with the result. So I got an absolutly wild idea: can I buy brass balls and drill through them to make the knobs? Just like the real thing? And if yes, how will I assemble the guardrails?
Some searching on AliExpress revealed that brass balls with a diameter of 0.9 mm were available and sold in packs of ... 200. Which was good because no doubt I would waste a few.

For me, it was an adventure: could I push my limits so far that I could drill a 0.5 mm hole through a 0.9 mm brass ball? And even better, drill another hole perpendicular to it!

I ordered the brass balls and it didn't take long before they arrived on my workbench. That was the easy part.

The next question was: how do you hold a 0.9 mm brass ball when you want to drill a 0.5 mm hole in it?

I had an ER16 collet with a minimum size of 1.0 mm. But how do you hold that ball in place while closing the collet? I fiddled a lot but every time ball escaped the crunch.

In the end, this was the trick:

• close the collet completely;
• place the ball on it;
• then slowly open the collet until you see the ball sink;
• then press it into the collet with your fingernail;
• and finally, carefully tighten the collet a little. Not too hard, because hey, it's just a small ball, right?

Drilling was then a matter of positioning the 0.5 mm drill bit correctly and drilling carefully. Such small drill bits really need to run at 20,000 rpm but that in turn required a delicate forwarding the dril bit and retracting it to clean the flutes.

And soon there was a convincing result.

So the answer is: yes, I can drill a hole in such a small ball. So the question of whether I could get a ball on the horizontal beam was answered.

The next question was how I could drill that ball at a right angle to insert a post. By then, I had come up with the idea of making a jig so that I could make the handrails repeatable and of the same size. After all, there had to be four of them, and because they are located next to each other in a very visible place, any difference in size would be immediately noticeable. To make the jig, I first had to take the measurements.

First, I measured the drill bit and then set the calliper to zero. This meant that any measurement I took would automatically be reduced by the thickness of the drill bit.

I inserted two of those drill bits into the etched holes.

By measuring the distance between the outer edges of the two drill bits, I obtained the centre-to-centre distance between two of the holes (which is the physically measured distance automatically reduced by twice the half thickness of the drill bit).

I incorporated all of this into a drawing of the handrails.

The distance between the posts was taken from the existing etch. I tried to establish whether that was entirely accurate, but I couldn't get much further than “approximately”. It doesn't really matter anyway, because the holes are already there, so I don't have much choice. The height of the guardrails is a bit of a guess, based on photographs and the one profile drawing we have.

To make the jig, I took a piece of L-shaped aluminium profile and milled it down to about half the thickness of the handrails.

The first cutter didn't last long. Having learned my lesson, I managed to keep the next one intact.

So, this is the jig.

Please note the following:

• For the rounded corner in the horiontal rails, where it merges into the front post, I simply milled away all the aluminium.
• The balls have some extra space at the intersections of the horiontal rails and the posts by drilling a 1.0 mm hole.
• The slots for the posts continue upwards because this was easy when making the mould and also to allow for the possible continuation of the posts during assembly, but the latter ultimately proved unnecessary.
• A rim has been milled into the bottom edge, which has been chosen so that the aforementioned feet can be soldered onto it in the correct position.
• And finally: aluminium was chosen because you can solder the handrails to it without also sticking the jig to it as well.

By the way, the rounded corner in the beam. It was created by bending it over a piece of brass rod measuring approximately 70% of the desired radius. The ‘30% smaller’ is to account for the brass springing back. By working in this manner, rather than freehand, you consistently achieve a virtually identical result.

And, of course, use a set ssquare to check whether the result is square. This one still needs a tweak.

The first two balls have been soldered to the horizontal rails.

As you can see, I used a clamp to hold the brass wire in place. That wasn't very practical, because you need one hand to hold the wire in place and two hands to adjust the clamp. But after soldering, the question arose as to how I was going to drill the holes for the vertical posts. The idea was to rotate the whole thing 90 degrees around the horizontal rails, but then I could no longer use this clamping method.

So I drilled a hole in the jig, tapped it to M2 and attached a piece of brass with a bolt. Now I could clamp more easily needing no more than two hands, and after soldering the balls, I could turn the handrails 90 degrees for drilling for the vertical posts.

This meant that the handrails could be drilled for vertical posts.

Don't forget that everything is very small. The brass wire is 0.45 mm, the head of the bolt measures 3.7 mm and the total width from left to right in this photo is approximately 45 mm.

After that, the whole thing was turned back into a horizontal position. The posts were soldered into the balls. The feet were soldered to the posts, using the previously milled edge to ensure correct placement. Finally, the brass wires were cut to length and finished.

The first one still in the jig.

And because a jig makes it possible to repeat work, I soon had four virtually identical copies.

The end result on the superstructure

It was a long road, but I'm a bit proud that it worked out.