Alan's Workbench

[Patrick Davey]

Lovely work Alan, this class of loco just screams 'GNRI' to me!

[Tullygrainey]

More PPs. The boiler came ready rolled which was a real help. It just needed tightening up a bit on the rolling bars. Boiler bands can be a bit of a struggle to fit. Three cheers for fibreglass pencils to clean up the mess afterwards.

 

The boiler needed quite a bit cut out of it to clear the motor, gearbox and wheels. The danger is always cutting too much away and leaving an unsightly gap somewhere so it's a time consuming exercise - boiler in, mark it up, boiler out, cut a bit, boiler back in again, fit the chassis, check for clearance, repeat until done.

 

The smokebox has three layers and needed a lot of heat to get everything soldered up.  I had the temperature controlled iron turned up full and still it was struggling. 

 

A trial run at Loughan Quay

 

 

Time for a tidy up, more fibreglass pencil and a scrub with scouring powder. 

 

[Mol_PMB]

Looking superb - an inspiring build and some useful tips too.

[Galteemore]

Wow that’s fabulous. I find guitar band clamps are great for holding boilers together whilst soldering. Know what you mean re cutting out / lots of careful measurements! Something mesmerising about watching those huge drivers !

Edited November 23 by Galteemore

[Tullygrainey]

That’s a useful tool David!

[David Holman]

Having never come across such things, had to Google them and discovered a weird and wonderful array of tools. Every day a school day!

 That said, will probably stick to soft iron garden wire to hold a boiler in shape for soldering.

[Patrick Davey]

21 hours ago, Galteemore said:

Wow that’s fabulous. I find guitar band clamps are great for holding boilers together whilst soldering. Know what you mean re cutting out / lots of careful measurements! Something mesmerising about watching those huge drivers !

Save a lot of fretting........

[Tullygrainey]

I've been avoiding fitting the brake gear to the PPs chassis up till now though some of the work was already done. Brake hangers using 0.7mm brass rod were soldered in at the time the chassis frames were assembled and the brakes themselves were made up and drilled to fit. Stringing it all together was tricky but slightly easier than I'd been dreading. 

This loco has brake pull rods on the outside of the wheels. I used these to help line up the brakes and solder them onto the hangers. Cross shafts were then fitted and soldered into holes in the bottom  of the brakes. Finally the pull rods were soldered onto the cross shafts which were then trimmed and filed to length.

 

I fitted the outside brake pull rods as far outboard as possible to allow for the wheels to be removed if ever necessary.

 

The superstructure now has most of its details added and is just about finished. I scribed a horizontal line along each side of the boiler to guide drilling the holes for the handrail knobs which were superglued in. The white metal castings were epoxied on.

 

If this was a tank engine we'd be done now but there are the makings of a tender still in the box. 

Alan

[Galteemore]

Excellent. I’m not a big fan of making up external pull rods. You’ve made nice work of these 

[Tullygrainey]

Me neither, David.  In fact, I'm not a fan of fitting brakes of any type. There's always the risk of brakes shorting on wheels, especially on compensated axles where the wheels are moving up and down and tilting so I tend to play safe and end up with a bigger gap between wheel and brake than I'd like.  In some of the scratchbuilds, I've used plastic brake gear from Gibsons which eliminates the risk of shorts but gluing these in place is never as secure as soldering metal ones. Swings and roundabouts

[Killian Keane]

It never ceases to amaze me Alan how you manage to churn out brass scratchbuilds of such quality in a matter of a few weeks, just incredible!

[Tullygrainey]

14 minutes ago, Killian Keane said:

It never ceases to amaze me Alan how you manage to churn out brass scratchbuilds of such quality in a matter of a few weeks, just incredible!

Thank you Killian, very much appreciated. However, much as I'd like to claim this one as a scratchbuild, it's a NorthStar kit for a change 

[David Holman]

Fab.

[J-Mo Arts]

That is absolutely incredible!!

[Mike 84C]

One word, Superb!! 

I am biased, i rather like the PP and PG.

[popeye]

A work of art Alan, would be a shame to paint it 

[Tullygrainey]

Thanks everyone. I have to say, I'm pleased with it. This NorthStar kit was well designed and went together without major trauma, though like many etched kits, there were the moments when three hands and asbestos fingers would've been helpful and the instructions sometimes leave you to your own devices. "Set up (chassis) frames in the preferred manner" makes sense if you've done it before but would leave a first-time builder at sea.

Incidentally, my clever clogs centring spring for the bogie (see post Nov 12 above) didn't work. It just succeeded in derailing it. I think the idea might be sound but the wire I used, 0.45mm diameter brass, was too hefty. I took it out, intending to replace it with 0.33mm but I found it ran ok without anything so that's how it is at present. The bogie is still likely to be a problem child. It has a small vertical coil spring exerting down pressure, the tension of which can be adjusted by tightening the nut holding the bogie in place. There's a fine line between getting enough tension to keep the bogie happy but not so much that the bogie starts propping the front coupled wheels off the track. More fun anticipated.

Alan

Edited Saturday at 09:31 by Tullygrainey
typo

[Galteemore]

Excellent Alan. Know what you mean about spring. I had to fiddle around with an industrial sized spring, trimming it to length to ensure the loco was getting the right balance of forces. If only I’d kept on at physics after O levels….

[Patrick Davey]

New commandment just announced:

”Do not covet thy neighbour’s GNR(I) PPs locomotive.”

guilty already…..

[Tullygrainey]

The rest of the PPs kit has now succumbed to my tender mercies. It was a challenging build partly because there are lots of seam joins which are tricky to get at if the aim is to keep as much of the solder as possible out of sight on the inside. Few fingers remained unburned. The etch also had a number of small errors and the instructions were peppered with work-arounds to deal with these. 

 

The tender chassis was built with the rear axle in fixed bearings and the other two moving up and down about 1 mm in slots and sprung with 0.33mm brass wire.

 

Brake rigging was put together using much the same approach as for the loco. This small sheet of foam plastic packaging is very useful for keeping things in line while the solder goes in.

Not much more to do now - arranging a coupling between loco and tender and fitting pickups to the rear tender wheels. The loco is only picking up on the 4 drivers so a bit of extra help from the tender would be useful. Essential maybe.

Alan

[Galteemore]

Fab work Alan. Is there also a vertical handrail to fit the cab cutouts ? 

[Tullygrainey]

4 minutes ago, Galteemore said:

Fab work Alan. Is there also a vertical handrail to fit the cab cutouts ? 

Whoops... missed those David! There's no mention of them in the written instructions but they appear in one of the diagrams- and in all the prototype photos of course so no excuses for not noticing   Many thanks. I'll add those.