Modelu's Workbench

Good progress there, Alan. Before giving up on soldering, you might try making a simple jig -- just pins in a block of wood -- to hold the various pieces of wire in place as you add each part. Maybe also use a high temperature solder (188 or above) for the core parts and 145 or lower for the parts added later.

 

That said, I have to ask why not just use the Alan Gibson cast brass injectors. They are a good representation of this particular type and can be fairly easily modified to match the slightly different arrangements on some other GWR tanks.

 

Nick

Alan, I admire your tenacity and bravery to tackle such a small item to be soldered. I agree with the use of jigs to hold pieces together while soldering or gluing. I was recently using and old cork sanding block for that purpose though what I really wanted was some polystyrene packing material.

 

Also, I am not sure if you did this or not, but soldering longer pieces of wire which are then trimmed off may help. In my case my fingers definitely need that kind of assistance!

If you want I can post a couple of pics which show the detail of an injector and the relevant part of the inside of the cab on a 1366 although it has the clacks on the backhead instead of a top feed so the pipework to them follows a different route.

 

On yours - if you want super accuracy you need a straight rod (not a pipe with a bend in it) from the cab to the water valve just below the tank.  On the 1366 this rod is above the feed to the clack so doesn't need to be cranked or bent but the 74XX could be different.

 

Also the steam feed pipe and the water feed into the injector are opposite each other and not at an angle - steam at the top and water coming in from underneath and it seems to be exactly the same on all the 74Xx pictures that I can find showing a decent view of an injector although the route of the steam feed from the cab front sheet varies.

Good progress there, Alan. Before giving up on soldering, you might try making a simple jig -- just pins in a block of wood -- to hold the various pieces of wire in place as you add each part. Maybe also use a high temperature solder (188 or above) for the core parts and 145 or lower for the parts added later.

 

That said, I have to ask why not just use the Alan Gibson cast brass injectors. They are a good representation of this particular type and can be fairly easily modified to match the slightly different arrangements on some other GWR tanks.

 

Nick

 

Cheers Nick for the advice, the higher melt solder and jig I'll give a go.  I've just looked at the Alan Gibson ones on your saddle tank and I see what you mean, they do look pretty good.  I guess I'm using this as a skills developing project so even though I'll probably end up ordering the AG injectors I'll persevere.  It all helps with brushing my skills up before tackling something like the 78xxx with all its appendages!

Alan, I admire your tenacity and bravery to tackle such a small item to be soldered. I agree with the use of jigs to hold pieces together while soldering or gluing. I was recently using and old cork sanding block for that purpose though what I really wanted was some polystyrene packing material.

 

Also, I am not sure if you did this or not, but soldering longer pieces of wire which are then trimmed off may help. In my case my fingers definitely need that kind of assistance!

 

Thanks, I'll give the longer bits of wire a go

If you want I can post a couple of pics which show the detail of an injector and the relevant part of the inside of the cab on a 1366 although it has the clacks on the backhead instead of a top feed so the pipework to them follows a different route.

 

On yours - if you want super accuracy you need a straight rod (not a pipe with a bend in it) from the cab to the water valve just below the tank.  On the 1366 this rod is above the feed to the clack so doesn't need to be cranked or bent but the 74XX could be different.

 

Also the steam feed pipe and the water feed into the injector are opposite each other and not at an angle - steam at the top and water coming in from underneath and it seems to be exactly the same on all the 74Xx pictures that I can find showing a decent view of an injector although the route of the steam feed from the cab front sheet varies.

 

That would be great if you didn't mind, it would be interesting to see what happens inside the cab.  I'll take this test piece apart tonight and have a go with a jig with the parts fitted as you describe.  Once I've got my 3D printer set up it will be interesting to see how it handles something as small as the injector body, if successful it will just need holes for the various wires drilling.

 

Cheers for the feedback gents, much appreciated!