Heather Kay
Western Thunderer
Aha! Yes, I get it now. Just wasn't familiar with the TLA. 
Mickoo's BR modelling
- Thread starter mickoo
- Start date
Dog Star
Western Thunderer
Now that has me stumped... what does that air-braked tank wagon look like?...Just wasn't familiar with the TLA.
AJC
Western Thunderer
Unless in jest - I don't speak TOPS and don't generally care to work it out - Three Letter Abbreviation (or, occasionally, Acronym).
Adam
mickoo
Western Thunderer
No problemsAha! Yes, I get it now. Just wasn't familiar with the TLA.
mickoo
Western Thunderer
Well I just checked the GAs for the Princess and it should be possible with the almost flat base to the frames to get a CSB set up on the bottom of the axle boxes, granted you may have to shave off 2-3 mm of the lower sides of the horn guides to give you the require upward deflection. On the class 08 I opted for a very soft 1 mm deflection but 0.5 mm may suffice.
All this talk has got me pondering the ever long issue of track, locos, perceived mass and realism, the niggle I'm trying to work around is the upward jolt of models when they hit the nose of adjoining track, it doesn't have to be much to give the visual distraction and even the 08 jolts when it hits a largish deformation. The issue is exaggerated with three point systems and equalising beams and to a certain extent horn guides with springs in and set screws to adjust the height and leaving little or no room for upward movement.
So I pondered what the solution might be and to decide that you really need to know what the problem is, in it's basic form it's either the track or the loco suspension (lack of). I did reason with some at Telford that if you made perfectly flat track then you would never need any suspension, you might achieve that with one board but a modular layout would present some heady challenges at board joins to maintain smooth track (less than 0.1 mm height discrepancy)
Taking the first problem, the track, traditionally we fix track to cork or some other form of base that may have some give in it, then we proceed to stick it solid with ballast and glue. However, I was very impressed with the S7 test track work, laid on paper over thin foam, here, when ballast is added it'll form a base on the paper and the foam underneath will still give some deflection, care would need to be taken when you glue the shoulders to still allow the track to flex a little.
As we all know real track flexes, it flexes a lot and in fact forms most of the local deflection in train movement. We ran some tests on the traverser with wheels crossing a 25 mm unsupported gap, normally a fish plate bolted to each rail will transfer some of the deflection into the adjoining rail before the wheel gets there, in unsupported joints this does not happen. The track base also has a huge impact, generally the older the formation the more deflection there is, so on out brand new terminal it was around 20 mm on ballast, on our older terminals it can be as high as 40 mm. Where our tracks make the unsupported leap between traverser and terra firm the formation is solid concrete or steel beam, each chair is supported on a nylon base, what did surprise many was just how much that nylon base deforms under load.
Here we can see the leading axle on the first bogie that has just made the transition, basically worst case scenario, also of note is that overall weight is not the deciding factor but axle load, in this case 21tons. What can clearly be seen is the track deformation as the wheel passes over, remember that this is about as a solid formation as you can get, steel decked bridges might be worse, but those often have longitudinal timbers under the chair to give some softening of the formation, all other formations will give more deflection.
So where is all this leading, well in our mini world we don't have any of this, should we? I think so, how much and how to achieve this is a subjective matter. I think adding track deflection along with loco suspension should give a better looking loco when moving over track work and I think more mass may well help.
Anyway digression over, time to try and put some of this in practice, just need to finally decide on a layout and then build something to run on it LOL
As an aside to the above image, on the wheel rim you can see a thin line, this is the 'witness' line, this is the minimum lathe turning line, basically this tyre is quite new and has a fair few miles left on it.
All this talk has got me pondering the ever long issue of track, locos, perceived mass and realism, the niggle I'm trying to work around is the upward jolt of models when they hit the nose of adjoining track, it doesn't have to be much to give the visual distraction and even the 08 jolts when it hits a largish deformation. The issue is exaggerated with three point systems and equalising beams and to a certain extent horn guides with springs in and set screws to adjust the height and leaving little or no room for upward movement.
So I pondered what the solution might be and to decide that you really need to know what the problem is, in it's basic form it's either the track or the loco suspension (lack of). I did reason with some at Telford that if you made perfectly flat track then you would never need any suspension, you might achieve that with one board but a modular layout would present some heady challenges at board joins to maintain smooth track (less than 0.1 mm height discrepancy)
Taking the first problem, the track, traditionally we fix track to cork or some other form of base that may have some give in it, then we proceed to stick it solid with ballast and glue. However, I was very impressed with the S7 test track work, laid on paper over thin foam, here, when ballast is added it'll form a base on the paper and the foam underneath will still give some deflection, care would need to be taken when you glue the shoulders to still allow the track to flex a little.
As we all know real track flexes, it flexes a lot and in fact forms most of the local deflection in train movement. We ran some tests on the traverser with wheels crossing a 25 mm unsupported gap, normally a fish plate bolted to each rail will transfer some of the deflection into the adjoining rail before the wheel gets there, in unsupported joints this does not happen. The track base also has a huge impact, generally the older the formation the more deflection there is, so on out brand new terminal it was around 20 mm on ballast, on our older terminals it can be as high as 40 mm. Where our tracks make the unsupported leap between traverser and terra firm the formation is solid concrete or steel beam, each chair is supported on a nylon base, what did surprise many was just how much that nylon base deforms under load.
Here we can see the leading axle on the first bogie that has just made the transition, basically worst case scenario, also of note is that overall weight is not the deciding factor but axle load, in this case 21tons. What can clearly be seen is the track deformation as the wheel passes over, remember that this is about as a solid formation as you can get, steel decked bridges might be worse, but those often have longitudinal timbers under the chair to give some softening of the formation, all other formations will give more deflection.
So where is all this leading, well in our mini world we don't have any of this, should we? I think so, how much and how to achieve this is a subjective matter. I think adding track deflection along with loco suspension should give a better looking loco when moving over track work and I think more mass may well help.
Anyway digression over, time to try and put some of this in practice, just need to finally decide on a layout and then build something to run on it LOL
As an aside to the above image, on the wheel rim you can see a thin line, this is the 'witness' line, this is the minimum lathe turning line, basically this tyre is quite new and has a fair few miles left on it.
mickoo
Western Thunderer
Another small up date, real life getting in the way of virtually everything I'd planned modelling wise over the weekend.
Finished up the tanks inner sides and bases, still have to add the splasher metal work that might be seen from lower angles, decided to tackle the firebox and moderately impressed with it, managed to form it almost right first time and be square and fit in the slot between the tanks. There's nothing more motivational that seeing bits on the model so decided to whizz up a firebox rear support bracket to see what it looks like from different angles (last photo) I'll probably keep that in there and maybe solder the firebox to it when its all painted.
I wanted to add the copper wire to the front inside join ready for rounding off and then add clothing bands, a quick look in the materials store revealed no 0.75 - 1.0 mm copper wire, so that'll be one of tomorrows tasks at work to procure said missing item. I'm tempted to go with the boiler next but concious of the gaping holes inside the cab so may tackle that next with false floors, spashers and handrail turn backs etc.
Finished up the tanks inner sides and bases, still have to add the splasher metal work that might be seen from lower angles, decided to tackle the firebox and moderately impressed with it, managed to form it almost right first time and be square and fit in the slot between the tanks. There's nothing more motivational that seeing bits on the model so decided to whizz up a firebox rear support bracket to see what it looks like from different angles (last photo) I'll probably keep that in there and maybe solder the firebox to it when its all painted.
I wanted to add the copper wire to the front inside join ready for rounding off and then add clothing bands, a quick look in the materials store revealed no 0.75 - 1.0 mm copper wire, so that'll be one of tomorrows tasks at work to procure said missing item. I'm tempted to go with the boiler next but concious of the gaping holes inside the cab so may tackle that next with false floors, spashers and handrail turn backs etc.
mickoo
Western Thunderer
And now with boiler, just one or two niggles that hopefully won't be too obvious once other paraphernalia goes on to distract the eye LOL.
Next? Not sure really, probably finish off this evening with attaching the cab front on the Std 5 and bolting the firebox on for alignment testing, tomorrow is the Sudbury meet so little metal work accomplished but next week will hopefully see that start of CAD work for the GE loco, it's an itch I have to scratch now, still not sure which model it is yet, or railroad LOL. It'll be a combination of scratch built chassis, tank and internal structure with CAD designed cab and other fiddly accurate plate work like step wells, radiator housing engine room shell and doors etc.
Next? Not sure really, probably finish off this evening with attaching the cab front on the Std 5 and bolting the firebox on for alignment testing, tomorrow is the Sudbury meet so little metal work accomplished but next week will hopefully see that start of CAD work for the GE loco, it's an itch I have to scratch now, still not sure which model it is yet, or railroad LOL. It'll be a combination of scratch built chassis, tank and internal structure with CAD designed cab and other fiddly accurate plate work like step wells, radiator housing engine room shell and doors etc.
mickoo
Western Thunderer
So, a small update this weekend, the smoke box, simple really, roll a couple of tubes and stick altogether.
Not so, determined to keep the front footplate cross piece for strength has meant that a slot needs cutting in the base of the smoke box, I did that after rolling as edges like this do not pass through all three rollers when the edge gets near to the bending roller, you end up with a bow in the material, hard to explain but easy to doodle on a beer mat LOL
I think the front is round and it all seems square and parallel though I seem to not have enough radius on the rear flange that the wrapper is riveted to, too late now as it's almost impossible to add a radius now, there's another couple of thin strips to go on the boiler, one 10 thou the other a 5 thou clothing strap, this'll give the final stepped ring arrangement in this area.
I've opted for the later long smoke box with exterior steam pipes and a row of rivets along the side just above the smoke box saddle, not present on all locos, exterior pipes or not, seems there are several types of smoke box kicking around?
This was the second wrapper I'd formed, the first has correctly spaced rivets, every 1.2mm however the anvil on the riveter with each new rivet part flattened the last one, so I cheated and went for rivets 2mm apart, although there are less rivets than 1:1 it actually looks more like the 1:1 than the correctly spaced riveted one, even though it's short several tens of rivets around the circumference, I've also just found out that one tank is 1mm longer than the other
The next stage will be the saddle and front dropped foot plate, for this I'm going to go left field and make the front frames from just behind the front face of the cylinders part of the body, an idea plagiarised from MOK and the recent build thread on the 4MT being the eureka moment on solving how to make the upper and lower parts of the frames easier to build from scratch. I'll probably do the same at the rear with a section from just around the rear driver rim to the rear buffer, that join will be harder to hide, thus only the drivers and cylinders will be removable for motor and drive maintenance. Of course if the rear join cannot be hidden then the rear section will have to be part of the drivers section of the chassis. It's a case of trying to add some rigidity to the rear chassis as on the model it'll be very thin in some areas depth wise, on 1:1 the chassis extends up through the footplate but quite a margin and in small area even above the wooden floor of the footplate.
Not so, determined to keep the front footplate cross piece for strength has meant that a slot needs cutting in the base of the smoke box, I did that after rolling as edges like this do not pass through all three rollers when the edge gets near to the bending roller, you end up with a bow in the material, hard to explain but easy to doodle on a beer mat LOL
I think the front is round and it all seems square and parallel though I seem to not have enough radius on the rear flange that the wrapper is riveted to, too late now as it's almost impossible to add a radius now, there's another couple of thin strips to go on the boiler, one 10 thou the other a 5 thou clothing strap, this'll give the final stepped ring arrangement in this area.
I've opted for the later long smoke box with exterior steam pipes and a row of rivets along the side just above the smoke box saddle, not present on all locos, exterior pipes or not, seems there are several types of smoke box kicking around?
This was the second wrapper I'd formed, the first has correctly spaced rivets, every 1.2mm however the anvil on the riveter with each new rivet part flattened the last one, so I cheated and went for rivets 2mm apart, although there are less rivets than 1:1 it actually looks more like the 1:1 than the correctly spaced riveted one, even though it's short several tens of rivets around the circumference, I've also just found out that one tank is 1mm longer than the other
The next stage will be the saddle and front dropped foot plate, for this I'm going to go left field and make the front frames from just behind the front face of the cylinders part of the body, an idea plagiarised from MOK and the recent build thread on the 4MT being the eureka moment on solving how to make the upper and lower parts of the frames easier to build from scratch. I'll probably do the same at the rear with a section from just around the rear driver rim to the rear buffer, that join will be harder to hide, thus only the drivers and cylinders will be removable for motor and drive maintenance. Of course if the rear join cannot be hidden then the rear section will have to be part of the drivers section of the chassis. It's a case of trying to add some rigidity to the rear chassis as on the model it'll be very thin in some areas depth wise, on 1:1 the chassis extends up through the footplate but quite a margin and in small area even above the wooden floor of the footplate.
richard carr
Western Thunderer
Looks really good Mick
Which rivetting tool are you using, I have the reynalds version, it comes with about 12 different anvils each with a diffent spacing. I think Lee marsh now sells these, but as you say sometimes the exact spacing isn't the best.
Richard
Which rivetting tool are you using, I have the reynalds version, it comes with about 12 different anvils each with a diffent spacing. I think Lee marsh now sells these, but as you say sometimes the exact spacing isn't the best.
Richard
mickoo
Western Thunderer
Richard, I'm using the GW version, I did some testing after I made the first wrapper and noticed that the punch mechanism had rotated, no issue you might image, except the punch is fitted into a hole in the mechanism head and retained with a grub screw, tightening the grub screw, and movement of the head supporting arm results in the punch not being perfectly central and thus mis shaped rivets, all one need do is rotate the punch head until it aligns with the die 
Having done that I then made a new wrapper and thought no more, after posting above comments I decided to try spacing at 1mm and they were much better <sigh> and then whilst looking atthe GA noted some more notes on rivet spacing. The measurement I had chosen to read was at top dead centre, this is where the two halves of the wrapper are welded together and the rivets are 1" either side of the weld, I'd assumed that all others would be spaced 2" around the wrapper, not so, they are spaced at 2 -5/8" so in our world about 1.5mm, so my 2mm whilst stil not right isn't as bad as I first thought.
Having done that I then made a new wrapper and thought no more, after posting above comments I decided to try spacing at 1mm and they were much better <sigh> and then whilst looking atthe GA noted some more notes on rivet spacing. The measurement I had chosen to read was at top dead centre, this is where the two halves of the wrapper are welded together and the rivets are 1" either side of the weld, I'd assumed that all others would be spaced 2" around the wrapper, not so, they are spaced at 2 -5/8" so in our world about 1.5mm, so my 2mm whilst stil not right isn't as bad as I first thought.
richard carr
Western Thunderer
Mick
I have to say I never really got on with my GW rivetting tool, it all looks really good but in practice I found it very difficult to get consistent rivets in the half etched bits that come in kits. It certainly looks good for scratch building though.
Richard
I have to say I never really got on with my GW rivetting tool, it all looks really good but in practice I found it very difficult to get consistent rivets in the half etched bits that come in kits. It certainly looks good for scratch building though.
Richard
mickoo
Western Thunderer
Richard, it does require a certain knack I'll agree, normally I dont use the X,Y table at all and just do it by eye, all of the Standard 5 cab was done by eye, but then those rivets are 3 mm apart and one slightly out doesn't show too bad, the first wrapper I did by eye, by eye I mean follow scribed marks but no mechanical assistance in lining up. The second I used the X,Y table as a back stop so that all the rivets were the same distance from the edge but there spacing was still done by following scribed marks. However if you look at the last image you'll see three rivets at the back edge of the wrapper at shoulder height, they're not consistant and that's the price you often pay for doing it by eye. Being as these were the last three I did (typical) they're staying and I'm just going claim it was a Friday afternoon job! LOL
The biggest issues I found with half etch is the size of the half etch hole, it's massive and the tip od the punch can wander around the half etch a lot and thus create inconsistancy, on my class 40 etch I made the half etch rivet holes half normal kit size (will add size later once checked CAD art work) and the GW punch tip spotted in each hole very accurately.
I've also got to punch some rivets on the short footplate in front of the tanks, down looking shots of Fowler 4P tanks are rare / non existant so accuracy is going to be an issue, as are any rivets up close to the tank, that will be an entertaining exercise in getting the model into the GW press. I may have to opt for a careful one or two with a dot punch and small Birmingham screwdriver
The biggest thing I found in helping using the GW tool is fixing it to a sturdy base, there's a 4mm ish hole in the base which convieninetly allows me to bolt it to my engineers table/ folding table/ fabrication slab/ paper weight come what ever (photo later for y'all who are interested), which is tapped with M4 holes, the table weights the best part of 7-8Kg so it isnt going anywhere, that solidity really helps when using the GW rivet press I find.
The biggest issues I found with half etch is the size of the half etch hole, it's massive and the tip od the punch can wander around the half etch a lot and thus create inconsistancy, on my class 40 etch I made the half etch rivet holes half normal kit size (will add size later once checked CAD art work) and the GW punch tip spotted in each hole very accurately.
I've also got to punch some rivets on the short footplate in front of the tanks, down looking shots of Fowler 4P tanks are rare / non existant so accuracy is going to be an issue, as are any rivets up close to the tank, that will be an entertaining exercise in getting the model into the GW press. I may have to opt for a careful one or two with a dot punch and small Birmingham screwdriver
The biggest thing I found in helping using the GW tool is fixing it to a sturdy base, there's a 4mm ish hole in the base which convieninetly allows me to bolt it to my engineers table/ folding table/ fabrication slab/ paper weight come what ever (photo later for y'all who are interested), which is tapped with M4 holes, the table weights the best part of 7-8Kg so it isnt going anywhere, that solidity really helps when using the GW rivet press I find.
mickoo
Western Thunderer
And now the start of the front end, hopefully buffer beams and the rest of the footplate added as well as the side valances to strengthen the wobbly front end 
The Fowler 4P has an odd front buffer beam with two cross members, almost like it's been extended and the old one left in place, you can't see much of it, but it explains why the main frames stop short of the visible buffer beam.
The Fowler 4P has an odd front buffer beam with two cross members, almost like it's been extended and the old one left in place, you can't see much of it, but it explains why the main frames stop short of the visible buffer beam.
Len Cattley
Western Thunderer
Looking good Mick.
Len
Len
mickoo
Western Thunderer
Great work Mick,
As you say she's really taking shape now. I for one would like to see a picture of your engineer's table please, it's always nice to add tools and equipment to my wish list
ATB Mick
Mick,
Here you go, quite simple at the moment, a steel slab 10"x10"x1" approximate, machined smooth and square on a big lathe and then some holes drilled in to accept Proxxon securing bolts and clamps (6mm? I forget now), as you can see it also holds my riveter nicely and ATM is set up to bed around a 4mm rod for valances etc. Total weight is just a touch over 10kg so it isn't going any where on a whim LOL
mickoo
Western Thunderer
And now the main frames, a lesson in pain (literally) and sheer bloody mindedness, there's a lot of holes in these locos!
On hindsight a milling machine would of been a dramatic saver here with those rectangular holes. I've tried to clean some up with a roughing mill in the bench drill....shock horror...once they had been butchered open with drill and fret saw. This seems to work ok with light cuts and care, some slight modifications (to drill) required plus a large spade full of ignorance, sheer luck and pixie dust. All milling was face milled so no need for depth control, hence the modification to allow the drill head to pop up clear of the work and then be reset down to face mill the next opening.
I've ordered some 'real' end mills so we'll see if they work any better, I think two layers of 25thou (1:1 loco is 1, 1/8" thick frames) is about as thick as you'd ever want to go with a drill head and chuck....raw down and dirty bodging from the back of the class LOL
Next up is to open out the axle holes to allow for CSB suspension, another Dick Dastardly concoction coming there I'd love to slot mill them out but suspect I'm going to have to bite the bullet and fret some slots in the bottom and persist with needle files. Then it'll be splitting time, frame spacers and with some more pixie dust remain all square.
I did make one rather fundamental error previously, the front frames are scale 30 mm over outside faces, S7 b2b is 31.3 mm add the thickness of the top hat bearing and you end up with frames a maximum of 29.3 mm over outside faces, which means, there's going to be a at least a 1 mm discrepancy between fixed front frames and removable main frames at the join behind the cylinders.....a subtle jog (0.5 mm each side) I fear will be in order at some discreet location behind the cylinders area, they must line up for my intended slot fixing method.
On hindsight a milling machine would of been a dramatic saver here with those rectangular holes. I've tried to clean some up with a roughing mill in the bench drill....shock horror...once they had been butchered open with drill and fret saw. This seems to work ok with light cuts and care, some slight modifications (to drill) required plus a large spade full of ignorance, sheer luck and pixie dust. All milling was face milled so no need for depth control, hence the modification to allow the drill head to pop up clear of the work and then be reset down to face mill the next opening.
I've ordered some 'real' end mills so we'll see if they work any better, I think two layers of 25thou (1:1 loco is 1, 1/8" thick frames) is about as thick as you'd ever want to go with a drill head and chuck....raw down and dirty bodging from the back of the class LOL
Next up is to open out the axle holes to allow for CSB suspension, another Dick Dastardly concoction coming there
I'd love to slot mill them out but suspect I'm going to have to bite the bullet and fret some slots in the bottom and persist with needle files. Then it'll be splitting time, frame spacers and with some more pixie dust remain all square.I did make one rather fundamental error previously, the front frames are scale 30 mm over outside faces, S7 b2b is 31.3 mm add the thickness of the top hat bearing and you end up with frames a maximum of 29.3 mm over outside faces, which means, there's going to be a at least a 1 mm discrepancy between fixed front frames and removable main frames at the join behind the cylinders.....a subtle jog (0.5 mm each side) I fear will be in order at some discreet location behind the cylinders area, they must line up for my intended slot fixing method.
mickoo
Western Thunderer
Frames separated and spacers added, hope all those holes were worth the effort, didn't add all of them, only the ones I thought would be seen through the wheels and motion, a trial fit and it all looks ok, I do need to sort some sort of support for the foot plate in front of the tanks, it's currently all a little flimsy at the moment.
