Mike G's Workspace.

[Dave Holt]

The Comet sprung system is identical to that used on the earlier Brassmasters chassis. I've built a Comet LMS Crab chassis and several Brassmasters locos (Black 5s and a Jubilee) and found no problem getting smooth running, despite the lack of adjustment between the slots in the frames and the holes in the rods. My experience is that the parts are dawn sufficiently accurate that the centre match. Perhaps I've just been lucky.
I agree with Mike that finding the right amount of ballast and where to put it, such that the loco sits level with the correct buffer height, is more of an issue. However, the models mentioned also satisfy those considerations although it might have involved adding weight under cab roofs, inside cab sides and under the cab footplate! 4-6-0s can be hard to balance due to the front end overhang beyond the drivers.
Dave.

 

[Mike Garwood]

Totally agree with everything that’s been said : Tim, Ian and Dave.
I won’t have a problem balancing this beast. Post 728 has a picture of the underside of the body. There is access to the front of the smoke box and right back to the centre driver. And a cathedral in the fire box. Not always the case and certainly this is true of etched kits.
If I’m honest. I think I messed the first set of rods up. The 56’s did not present any problems at all. I suspect that when dear Geoff Brewin re-drew most of the chassis in the Comet collection. He may have overlooked the thickness of the material. 30 thou is normal width of frames. When I measured the thickness of the Grange chassis frames it was 0.4 mm. If my maths is right that’s thicker than 30 thou (maths & physics were never my strong points). Because this chassis pack covers a multitude of GWR engines. It may well have been one of the first to be released and consequently using a thicker brass - now NS. Pure conjecture of course, but it does sort of fit the logic of what’s happened.

Mike

 

[simond]

30 thou is a midge‘s todger more than 0.75mm.

in round numbers 40 thou is a millimetre. In less round numbers it is 39.37.

 

[Mike Garwood]

30 thou is a midge‘s todger more than 0.75mm.

in round numbers 40 thou is a millimetre. In less round numbers it is 39.37.

Hmm. Definitely got some mistakes with my memory and my maths! Thanks for the correction Simon. I have a Brassmasters Jubillee on the shelf of shame. That has thinner frames than the Grange.
Mike (shaking his head in shame)

 

[Dave Holt]

Mike.

I've just measured the frames on a part-built Brassmasters Black 5 - 0.46 mm (ish), so the Comet frames are about the same. Full sized loco frames ranged from about 1" to 1.25" thick, so 0.4 mm isn't wildly too thick. 0.33 mm would be very flimsy and require full frame stretchers, as per prototype - and have the stiffness of steel? Also, as the frame thickness provides the bearing surface for the axleboxes, in this case, very thin frames could suffer or cause excess wear in the horns?
Dave.

 

[Mike Garwood]

And yet another update...





Another day, another coat of paint...
Cab roof and smoke box painted in Vallejo Acrylic Nato black. The masking took longer than the spraying! I've also lined out 3 coaches today, having just completed the Hawksworth third a few moments ago.




GWR Brake third.



LMS Corridor Composite. All lined in pressfix transfers. I tried to get some more of these from HMRS, but nearly all the choices were only in Methfix. Never ever used these, but that's what arrived in yesterdays post. The alternative is me using a bow pen....!

Gotta be honest, pretty pleased. One more to go...I've ordered the coach numbers from Railtec for the 3 GWR coaches. I found a number in the running numbers in one of my packs from Model master - did anyone take over this range?

Have a great weekend.

Stay safe

Mike
(off to Barrow Road tomorrow)

 

[76043]

I've been meaning to ask about Comet springing for a while. I have a Comet pannier chassis and a Bachmann body and a packet of hornblocks and springs!

My question is quite simple I hope: I had always assumed the weighting might need to be heavier than other methods, is this the case?
Cheers
Tony

 

[Mike Garwood]

I've been meaning to ask about Comet springing for a while. I have a Comet pannier chassis and a Bachmann body and a packet of hornblocks and springs!

My question is quite simple I hope: I had always assumed the weighting might need to be heavier than other methods, is this the case?
Cheers
Tony

In short - yes.
Just remember that the front of the engine has to weigh the same as the back. It has to balance at the mid point of the footplate. I don’t mean on a pencil tip, but your finger acting as a fulcrum point.
The Bachman pannier has the water tanks to use to get a lot of lead sheet into, cab floor and the smoke box.
I have 2 of these to do this year an 87, 64 and a 16. The first 2 will use Gibson milled frames (that will be a first) and the 16 has a Rhumney models Chassis - looking forward to that. Justin’s stuff is so well designed.
Hope that helps?

The visit to Barrow Road proved worthwhile: the 51xx. - the running has improved again with more miles added to its testing. The County was really good up until the grub screw on the gearbox came loose. That’s not the first time that’s happened. I think I’m going to add some glue to the grub screw to keep it in place. It’s highly unlikely that I’ll have to replace the gearbox.

Stay safe

Mike

 

[simond]

Nail varnish. You can see it, and you can get it off with a drop of acetone. Better than glue…

 

[Tony Comber]

I've used clear nail varnish for years to stop cranpin nuts unwinding themselves.

 

[Phil O]

Opticians use nail varnish to secure errant screws in glasses frames, so I bought some to secure nuts and bolts. I wasn't allowed to use 'er indoors, nail varnish, besides it's bright red.

 

[simond]

Opticians use nail varnish to secure errant screws in glasses frames, so I bought some to secure nuts and bolts. I wasn't allowed to use 'er indoors, nail varnish, besides it's bright red.

I didn’t know that. Bright red is ok inside the gearbox. Perhaps not ideal for crankpins.

 

[76043]

Thank you Mike for further details. Don't suppose you've got a rough idea of the ideal weight for a pannier then please? The tip on nail varnish is fab.
Cheers
Tony

 

[Mike Garwood]

Hi Tony

I have 2 Panniers, both have compensation - never built a sprung version..yet. They weigh an average of 150 gms. To put that in context, they will both run away with 3 Comet coaches without a struggle. Both have High Level motors and gear box.

Mike

 

[76043]

Thanks Mike, I guess 150g is a starting point but clearly more is needed. Would be helpful if Comet suggested an ideal driven wheel weight for their springing system, would enable us modellers to plan better, but I've not found anything in the various guides and instructions.

I guess compensation is easy on a Pannier, but I have the springs and fancy using them.
Cheers
Tony

 

[Mike Garwood]

I've been working on the Grange for the last few days. I opted for a sprung bogie and set about re-working the Comet etch.





If the worse comes to the worse, there's always the etch I did (below), I've used this design before on my County...and it works. I'll need to remove the cosmetic sides if this doesn't work and then spend more money at PPD!



If your wondering why there are blank spaces in the hatched area, it's because I cannot get it to 'fill' without flooding the holes. And yes all the lines are bounded. I've passed the problem onto someone who knows way more than I do. Next job is to ream out the coupling rods...

Stay safe

Mike.