Steph Dale
Western Thunderer
This evening I realised I had bog-all chance of getting to sleep until the temperature dropped a little (still just over 26 degreesC in the bedroom!) so I thought I'd go and see if I could occupy myself for an hour or two in the workshop.
Coupling rods and the shortening thereof. This is a trick which, once used, is never forgotten. I learnt it in my 4mil days playing with the odd set of Alan Gibson 'universal' coupling rods. Shortening etched rods is pretty straightforward. Incidentally, this is demonstrating just one option for construction; if you've got the chassis constructed you can jig the rods from there...
But I haven't got the chassis done, in fact I want to use the rods to jig up the hornblocks. So I had to start by making a quick jig. As per usual the emphasis is on speed and repeatability rather than getting the coupling rod centres correct to the nearest gnat's crotchet. So that'll be cocktail sticks, wire and bit of chipboard then:
And the etched rods from Slater's. I started by knocking out all the rods for one half of the set, with the slender rods of the prototype I decided not to use the extra half-etched layers for the bosses; the half etch in the rods would be enough:
First job was to remove the attachment tag on the top of the boss on the centre layer of the rods and put a 'V' in the top of the box with a 3-square (i.e. triangular) needle file; this optional stage will form a centre when I drill here later. Inserting a short length of wire in to the hole formed will portray the corks for the oil boxes:
And so to fiddling. Working on one part/layer at a time they're cut through, the cut edge filed smooth and deburred on the smaller piece. The larger piece is marked up:
Then cut and file until the two edges meet as accurately as possible. Careful it's not too tight a fit and you end up pushing the cocktail sticks out of whack:
And now the middle layer, note that the layers will overlap when assembled:
And now all three layers are done:
Assemble the layers, this view showing clearly the way the two parts of the rod now formed will meet:
And tack solder around the bosses:
Reassemble on the jig; the strip of brass is just used as packing to make up for the half etch thickness of the outer layers of the rod. Tack the two rod sections together. Yes, I did have a second bite at this particular cherry in order to get the two sections to align better:
Run solder round and they're now ready for cleaning up:
These rods are steel so heat control is a little different to brass. I also use Baker's fluid as flux and 188 solder, which is a good combination for this sort of work. I'll use 145 solder to attach the corks and perhaps the knuckle pin.
The other rod sections will follow when I get a chance to spend another hour at the bench...
Steph
Coupling rods and the shortening thereof. This is a trick which, once used, is never forgotten. I learnt it in my 4mil days playing with the odd set of Alan Gibson 'universal' coupling rods. Shortening etched rods is pretty straightforward. Incidentally, this is demonstrating just one option for construction; if you've got the chassis constructed you can jig the rods from there...
But I haven't got the chassis done, in fact I want to use the rods to jig up the hornblocks. So I had to start by making a quick jig. As per usual the emphasis is on speed and repeatability rather than getting the coupling rod centres correct to the nearest gnat's crotchet. So that'll be cocktail sticks, wire and bit of chipboard then:
And the etched rods from Slater's. I started by knocking out all the rods for one half of the set, with the slender rods of the prototype I decided not to use the extra half-etched layers for the bosses; the half etch in the rods would be enough:
First job was to remove the attachment tag on the top of the boss on the centre layer of the rods and put a 'V' in the top of the box with a 3-square (i.e. triangular) needle file; this optional stage will form a centre when I drill here later. Inserting a short length of wire in to the hole formed will portray the corks for the oil boxes:
And so to fiddling. Working on one part/layer at a time they're cut through, the cut edge filed smooth and deburred on the smaller piece. The larger piece is marked up:
Then cut and file until the two edges meet as accurately as possible. Careful it's not too tight a fit and you end up pushing the cocktail sticks out of whack:
And now the middle layer, note that the layers will overlap when assembled:
And now all three layers are done:
Assemble the layers, this view showing clearly the way the two parts of the rod now formed will meet:
And tack solder around the bosses:
Reassemble on the jig; the strip of brass is just used as packing to make up for the half etch thickness of the outer layers of the rod. Tack the two rod sections together. Yes, I did have a second bite at this particular cherry in order to get the two sections to align better:
Run solder round and they're now ready for cleaning up:
These rods are steel so heat control is a little different to brass. I also use Baker's fluid as flux and 188 solder, which is a good combination for this sort of work. I'll use 145 solder to attach the corks and perhaps the knuckle pin.
The other rod sections will follow when I get a chance to spend another hour at the bench...
Steph
