Is this a set of coupling rods, or a full valve gear set, since your description leads me to think you may have the connecting rods too?

You might like to look on Bill's website. It is rather sparing with instructions but I found some for the 56xx chassis which includes a page for etched rods. You should find that the rectangular bits to which the sections of rod are attached have little etched dimples. These are meant to be drilled out to take 0.045mm wire which acts as locating pins.

Is this the supplier who allegedly didn't believe in providing instructions, on the grounds that if you didn't know what to do with the kit already you weren't competent to build it? It doesn't seem the best way of encouraging folk to develop in the hobby

Is this the supplier who allegedly didn't believe in providing instructions, on the grounds that if you didn't know what to do with the kit already you weren't competent to build it? It doesn't seem the best way of encouraging folk to develop in the hobby

Yup although some of the stuff sold was made for others and Bill has no idea what it is. The rather detailed class 25 sideframes are a case in point! He did tell someone he was too young for P4 before now too..

Anyway, post up a piccy of the etch if you need any help on the bits, guys on here should be able to figure them out.

For the rods i've done I used Carrs 188, tinned all layers (i've done 4 layers rods before!). Plenty of flux and they should sweat together. I didn't use Bill's alignment method as these didn't have it so used drills through the holes. Those rods had a proper knuckle joint too and that had the rod that fitted between the Y joint oiled before fitting to ensure I didn't solder solid.

Ideally I believe an RSU would be used for this sort of layer work but I managed without. If it goes a bit wrong you can desolder it all, clean up and try again.

You might like to look on Bill's website. It is rather sparing with instructions but I found some for the 56xx chassis which includes a page for etched rods. You should find that the rectangular bits to which the sections of rod are attached have little etched dimples. These are meant to be drilled out to take 0.045mm wire which acts as locating pins.

That's exactly right. The idea behind the plain lengths underneath the rods is to help with handling during assembly. You then separate them from the rods once assembly is complete.

The 56xx chassis instruction diagrams are a reasonable guide to the principle.

I generally use 188-degree solder to assemble rods. If I'm really desperate, I have assembled them in the past using electrical multicore solder, and that's worked perfectly well!

Is this the supplier who allegedly didn't believe in providing instructions, on the grounds that if you didn't know what to do with the kit already you weren't competent to build it? It doesn't seem the best way of encouraging folk to develop in the hobby

Yes. Bill is a bit idiosyncratic in that respect, and it means you have to learn how to think like he does..... Not always easy.

Here's a scan of the Rebuilt Merchant Navy valve gear etch. Click on it to see it full-size:

I've edited the first post with a photo. Need to order some flux from C&L so will get some 188 degree solder at the same time. In the past I've had problems getting the two parts to sweat together, despite applying the temp controlled iron set to its max temp (400odd degrees C) Not exactly sure what I've been doing wrong.

As long as the soldering iron tip is clean, I brush flux on the surfaces to be joined, and wipe molten solder from the iron's tip onto those surfaces. I use a 25w Antex; never had a problem.

The long rod on the RHS of the etch is 3 parts, should all 3 be sweated together at once?

Those are the three layers of the connecting rod so, yes, they should be pressed together. If you can do it in one "hit"....

.... how would you connect the the little bits (I see Hornby have used small rivets, but I guess thats not practical...)

0.55mm dressmakers' pins (also known as "Lill" pins) are a better alternative to rivets, as they don't usually need you to drill a larger hole to accommodate them. You will have to file the head down, so that clearances, etc. are preserved.

If the etched holes are too big for Lill pins, then you might want to see what diameter wire fits closely, e.g. 0.7mm. As long as you can keep solder away from the moving joint (a little oil plus tracing paper will do), the wire can then be cut to form a short pin.

It looks like everything is there apart from the sliding bits by the cylinders (which would of course be one of the bits that ideally I wanted changing as ones a bit sticky on the slider)

I think you're referring to the valve piston rods? Most of the advanced kits provide these as lost-wax castings. You might want to have a go at fashioning your own from brass or nickel-silver wire.

Do you have a good close up photo of the prototype valve gear in front of you?

Partial view: Click here - actually a Rebuilt "WC", but the arrangement is virtually identical to that used on the Rebuilt "MN" . Clearer view HERE

Broadside view: Click here

....I wonder if maybe its a problem with the tip

Clean it with some wire wool, or a cheap flat needle file to take the crud off. Then dip it in some flux (Carrs Yellow Label is good) and then melt solder over that; that's what I do with my Antex.

For soldering the pivot pins in place, I change down to an 18w Antex and 145 solder.

Will you be allowing the bogie axles to rise and fall independently of the bogie frame?

It aught to be the amount the dammed thing cost! (big Antex job, says its rated at 55W on the control box)

I wonder if maybe its a problem with the tip

Not sure if you fixed this but the expensive Antex ones are rather good if overkill for 4mm compared to a couple of cheap single use irons imho.

It does sound like the tip was at fault. Some Antex tips can last for years as per my current one but others don't seem to last 5 minutes! It may be to do with how well the tinning goes or if their coating is variable. Still prefer them to plain tips however.

Glad the build is going well anyway.