readingtype
Western Thunderer
Excellent, thanks - an entirely different approach. N/S rod goes on the shopping list for Abrail tomorrow morning!
Ben
readingtype’s workbench
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Ben
readingtype
Western Thunderer
Well, yes, I see your various points ... Thing is - we had to have quint sets for the Orchard Wharf project. You just can't do GE suburban without them. And I remain grateful that these kits appeared within a year of our group sticking its collective neck out! My intention is these give the right impression when viewed from 2' 6" which is as close to the front of the layout as they can get without derailment.
Ben
readingtype
Western Thunderer
I wasn't! Didn't see any such thing as n/s rod on sale (and didn't get to see everything there was). An enjoyable event nonetheless.
Tim Watson
Western Thunderer
Try this, Ben.
www.scalemodelshop.co.uk
Tim
Scale Modelling Nickel Silver Rod Albion Alloys - Scale Model Shop
Nickel Silver Rod by Albion Alloys, great for scale models, available from Scale Model Shop UK, Fast UK Delivery, 5* Customer service, Live Stock Levels
www.scalemodelshop.co.uk
Tim
adrian
Flying Squad
Also often recommended - for different sizes / lengths of n/s wire
and
www.cambrianmodelrail.co.uk
Metal Materials, Cutting tools Sundries Model Makers Engineering Tools
Tools & materials for the hobbyist. Nickel-silver, brass, plastics, tufnol. Wire, rod, bar, sheet, metal materials, cutting tools, sundries
www.metalsmith.co.uk
and
Nickel Silver Wire
Straight Nickel Silver wire mainly in 250cm lengths in various diameters.
www.cambrianmodelrail.co.uk
readingtype
Western Thunderer
I didn't allow myself a chance to get n/s rod. Thank you for the suggested sources, those will not be wasted! I decided this time to keep moving, using brass that I already had. There followed much folding and tinning of L shaped hangers. Much of this afternoon was along these lines:
A better informed approach to the project overall would have marked everything out, and drilled and cut, before putting things together. I have to confess that at that stage, although I was looking at drawings, I was, so to speak, hung up sufficiently on the underframe trussing that I looked straight through the running boards. Later, of course, it became obvious I had my priorities inside out. The running boards will hide the missing trusses for as long as they're missing!
Five carriages later I am now out of K&S #815026 and one running board had to include a join.
A better informed approach to the project overall would have marked everything out, and drilled and cut, before putting things together. I have to confess that at that stage, although I was looking at drawings, I was, so to speak, hung up sufficiently on the underframe trussing that I looked straight through the running boards. Later, of course, it became obvious I had my priorities inside out. The running boards will hide the missing trusses for as long as they're missing!
Five carriages later I am now out of K&S #815026 and one running board had to include a join.
Phil O
Western Thunderer
Ben,
There was nothing for the modeller there, so you didn't miss anything. We were looking for bits to replace gremlin affected parts of our layout.
readingtype
Western Thunderer
The long term the fix for the incorrect footplate height on this Trix ex-KPEV T3 is a new set of frames. As this thread shows, that would challenge my current skills. Meantime, the 'OBK' coupling hook needs adapting as it's fitted to the buffer beam and the artificially raised footplate makes it too high to couple to anything else.
Step one is to try lengthening the striker/hook that it doesn't run over the top of the loop on the opposing coupling but lifts it, as intended.
A comparison with jig shows the height difference
My first attempt has failed. Adding 0.7mm brass rod does catch the loop, but the striker obstructs the hook on the opposite coupling so the loop cannot be caught by the hook. Hope that's clear? More later...
Step one is to try lengthening the striker/hook that it doesn't run over the top of the loop on the opposing coupling but lifts it, as intended.
A comparison with jig shows the height difference
My first attempt has failed. Adding 0.7mm brass rod does catch the loop, but the striker obstructs the hook on the opposite coupling so the loop cannot be caught by the hook. Hope that's clear? More later...
Prussian T3
New
readingtype
Western Thunderer
I moved the brass rod from the front to the side of the hook, reducing the extra projection to the minimum. It looks yet uglier (though would still disappear when blackened). It performs better but it's still marginal, and that's not really satisfactory.
There are two reasons intrinsic to the coupling and the loco that mean it doesn't work every time. I fixed one: the striking surface had to be filed smooth to prevent the hoop sticking as it slides up.
The other is partly a weakness in the way this particular coupling is fixed (basically into slightly bendy plastic forming the buffer beam). The coupling can pivot slightly in its mounting hole. Thehook loop will hit the striker below the fulcrum. This tends to make the coupling pivot downwards. Having pivoted downwards, the slope of the striker is steeper and that makes the hook loop much less likely to slide up it. Just a small change in the angle has a significant effect.
There's a third reason that can't be controlled at all, and that's the fact that H0 NEM coupling pockets quite often droop under the weight of the coupler. So different vehicles may present thehoop loop at different heights, and the lower the hook loop the less likely it is to slide up and over the hook. So much for the standard -- and the more expensive rolling stock tends to have thinner, more flexible plastic underframes and is therefore more likely to suffer from this fault. The wagon depicted is hovering on the edge of acceptability in this respect.
Back to the T3. I'm going to think about new frames.
[Edited to resolve weak brain swapping and combining hook and loop here and there]
There are two reasons intrinsic to the coupling and the loco that mean it doesn't work every time. I fixed one: the striking surface had to be filed smooth to prevent the hoop sticking as it slides up.
The other is partly a weakness in the way this particular coupling is fixed (basically into slightly bendy plastic forming the buffer beam). The coupling can pivot slightly in its mounting hole. The
There's a third reason that can't be controlled at all, and that's the fact that H0 NEM coupling pockets quite often droop under the weight of the coupler. So different vehicles may present the
Back to the T3. I'm going to think about new frames.
[Edited to resolve weak brain swapping and combining hook and loop here and there]
Last edited:
readingtype
Western Thunderer
In the evening I pondered the idea of replacing the frames. Some years ago I created a CAD drawing at 1:1 from the KPEV's drawings of the loco which were then available as scans from an online publisher. I've taken a 1:87 scaled copy of these as the starting point for constructing my own chassis.
To turn the frame sides into the basis of a chassis they have to carry the axles in some kind of bearing. The diameter of the axles is 2.5 mm. So I guess that means to use commercial hornblocks I will need to drill them out from 2 mm inside diameter: not something I have ever tried. But I added the axles and the overall wheel diameter including flange to the 1:87 CAD drawing.
By offering up this drawing to the footplate moulding I could see how the extra 1 mm height in the model had been achieved. It corresponds to the thickness of the footplate (1 mm) being placed 'on top' of the top surface of the scale frame side member. To lower the footplate, 1 mm needs to be removed from here. But the wheel flanges would then contact the underside of the footplate. So a compromise is needed: either the wheel diameter has to be reduced (not possible, having replaced the wheels with RP25:88 ones already) or the footplate needs to remain slightly higher than it should be - say 0.5 mm.In this case the coupling hook issue I described will probably still remain, but the length of the extended striker could be reduced a little which would improve the chances of coupling up successfully.
I think it's time to put the whole lot back together, play with it as it is, and then perhaps cut some trial frame sides.
To turn the frame sides into the basis of a chassis they have to carry the axles in some kind of bearing. The diameter of the axles is 2.5 mm. So I guess that means to use commercial hornblocks I will need to drill them out from 2 mm inside diameter: not something I have ever tried. But I added the axles and the overall wheel diameter including flange to the 1:87 CAD drawing.
By offering up this drawing to the footplate moulding I could see how the extra 1 mm height in the model had been achieved. It corresponds to the thickness of the footplate (1 mm) being placed 'on top' of the top surface of the scale frame side member. To lower the footplate, 1 mm needs to be removed from here. But the wheel flanges would then contact the underside of the footplate. So a compromise is needed: either the wheel diameter has to be reduced (not possible, having replaced the wheels with RP25:88 ones already) or the footplate needs to remain slightly higher than it should be - say 0.5 mm.In this case the coupling hook issue I described will probably still remain, but the length of the extended striker could be reduced a little which would improve the chances of coupling up successfully.
I think it's time to put the whole lot back together, play with it as it is, and then perhaps cut some trial frame sides.