My 7mm dabblings
- Thread starter mickoo
- Start date
Eastsidepilot
Western Thunderer
Wasn't a Basil Fawlty moment then Mick 
....at least it wasn't a finished model mate
ATB, Col.
....at least it wasn't a finished model mateATB, Col.
Jordan
Mid-Western Thunderer
You have my sympathy Mick; even if I didn't have a shout, I'd probably have a quiet cry dropping a model like that. 
I dropped one of my US 1:48 Boxcars from my loft this week - down the hatch and naturally right down the stairs to the hallway
...fortunately it was in it's box at the time & emerged unscathed... *phew* 
I dropped one of my US 1:48 Boxcars from my loft this week - down the hatch and naturally right down the stairs to the hallway
...fortunately it was in it's box at the time & emerged unscathed... *phew* 
Rob Pulham
Western Thunderer
Well it looks like a David Andrews box Mick
And my vote is for Holbeck, it's not far from me and Chris plans a painting of the shed at some point - based on this photo by Bill Wright on Flickr.
And my vote is for Holbeck, it's not far from me and Chris plans a painting of the shed at some point - based on this photo by Bill Wright on Flickr.
mickoo
Western Thunderer
Moving swiftly on I managed to get some work bench time this weekend.
Work pressures and long days on the 'new' project at work leave little energy for hobbies these days
Anyway, progress so far, hopefully the tender bodywork will all be done by this weekend and the majority of the chassis too, then it's onto the loco.
Fortunately I'd already opted to have a full coal capacity, just as well as the kits coal space side sheets are....well they don't fit by a country mile, I could scratch up replacements that'd fit but no need as the coal will be piled very high on the finished model.
The rest has gone together pretty much to the plans, dot to dot modelling really, next time I'll make a better jig for rolling the top of the side sheets, up close this one isn't as smooth as I'd like, the curve is uniform but it's the edge that's a little battered, luckily much like the real thing after it's had several tons of coal dropped on it from a great height. Other than a few really obvious issues (holes in the rear of buffer beams for buffer nuts etc which require scratch parts fabricating) it'll be an out of the box project.
I am surprised at how thick the material is, having to change to a bigger tip and punch the temp up to 400°C on the larger parts, quite a different proposition to the recent self etched CAD EMD Spartan cab project.
Apologies for the grainy poor pictures, just too tired to post edit so uploaded warts and all.
Work pressures and long days on the 'new' project at work leave little energy for hobbies these days
Anyway, progress so far, hopefully the tender bodywork will all be done by this weekend and the majority of the chassis too, then it's onto the loco.
Fortunately I'd already opted to have a full coal capacity, just as well as the kits coal space side sheets are....well they don't fit by a country mile, I could scratch up replacements that'd fit but no need as the coal will be piled very high on the finished model.
The rest has gone together pretty much to the plans, dot to dot modelling really, next time I'll make a better jig for rolling the top of the side sheets, up close this one isn't as smooth as I'd like, the curve is uniform but it's the edge that's a little battered, luckily much like the real thing after it's had several tons of coal dropped on it from a great height. Other than a few really obvious issues (holes in the rear of buffer beams for buffer nuts etc which require scratch parts fabricating) it'll be an out of the box project.
I am surprised at how thick the material is, having to change to a bigger tip and punch the temp up to 400°C on the larger parts, quite a different proposition to the recent self etched CAD EMD Spartan cab project.
Apologies for the grainy poor pictures, just too tired to post edit so uploaded warts and all.
BrushType4
Western Thunderer
Yeah, not bad. I've just been counting your rivets and the third row from the back is not correct for your time frame unless you're modelling a later version. They had to add extra rivets to strengthen the whatit's holding it all together across the whole class after an unfortunate matter involving a certain Miss. Apart from that it looks pretty good. 
mickoo
Western Thunderer
Yeah, not bad. I've just been counting your rivets and the third row from the back is not correct for your time frame unless you're modelling a later version. They had to add extra rivets to strengthen the whatit's holding it all together across the whole class after an unfortunate matter involving a certain Miss. Apart from that it looks pretty good.
Darn, I was hoping the fuzzy pictures would hide that little error
Seriously, next time I'm going for the smooth sided variant, much easier to form the cant rail curve and solder the joint where the rear end joins the sides, if it's not perfect...and it is very hard to make it so due to some small errors in the slot and tabs and etch work....then you end up sanding or filing to trim and thus risk removing some of the rivet detail.
mickoo
Western Thunderer
Progress has been somewhat slower than I really wanted, the last 5% taking 95% of the time, mind more like the last 30% taking 98% of the time LOL.
Still some work to do at the front end and then hopefully get the innards sorted before tackling the chassis.
The less than perfect cant rail plate work isn't as bad as I'd originally noted, once the brass has been washed and man handled a few times it becomes less polished and toned down, which means the deformities are more subtle, almost pleasing.
A couple of issues so far for future DA kit builders, I've checked the Princess and Jubilee and both seem to suffer the same problems, as do other DA kits I've seen built on the web.
Slots and tabs, these have a rather generous tolerance, such that any item placed in the slot will invariably have a hole on one side or the other, this being a particular pain in the tank sides where they meet the running plate, the same goes for where the steps fit into the rear of the tank, resulting in some 'filling' with solder to fill the holes. The same applies to some of the half etched art work, the steps have a slot that even if the sides are bent 90° will leave a thin gap, the real loco has the sides at around 60° so there's a large trough to fill.
They're minor points but all add to the build time to rectify.....if you so choose too
Right, onward, time to bite the bullet and fix the innards in and then seal it up with the front end.
Still some work to do at the front end and then hopefully get the innards sorted before tackling the chassis.
The less than perfect cant rail plate work isn't as bad as I'd originally noted, once the brass has been washed and man handled a few times it becomes less polished and toned down, which means the deformities are more subtle, almost pleasing.
A couple of issues so far for future DA kit builders, I've checked the Princess and Jubilee and both seem to suffer the same problems, as do other DA kits I've seen built on the web.
Slots and tabs, these have a rather generous tolerance, such that any item placed in the slot will invariably have a hole on one side or the other, this being a particular pain in the tank sides where they meet the running plate, the same goes for where the steps fit into the rear of the tank, resulting in some 'filling' with solder to fill the holes. The same applies to some of the half etched art work, the steps have a slot that even if the sides are bent 90° will leave a thin gap, the real loco has the sides at around 60° so there's a large trough to fill.
They're minor points but all add to the build time to rectify.....if you so choose too
Right, onward, time to bite the bullet and fix the innards in and then seal it up with the front end.
mickoo
Western Thunderer
Small amount of progress on the A1 tender, virtually all of the front end done, just a couple of brackets, coat hooks and streamlined coal cover, the hand brake and water scoop stands will be added once it has been primed and painted and I'll be adding a very thin veneer strip wood decking to represent the wooden boards better, only the cast fittings to go on and then onto the chassis.
Reality is I spent too much time filling all the little half etch gaps in the foot steps and other minutia with a seam of solder, I'm hoping a quick run down them with a line of paint will seal all the other little holes and make them look like the bent pieces of flat plate in the case of the steps and sealed rear tank top, some strategic coal in there will hide the rest I hope.
Reality is I spent too much time filling all the little half etch gaps in the foot steps and other minutia with a seam of solder, I'm hoping a quick run down them with a line of paint will seal all the other little holes and make them look like the bent pieces of flat plate in the case of the steps and sealed rear tank top, some strategic coal in there will hide the rest I hope.
mickoo
Western Thunderer
Moving ever onward, time to tackle the tender chassis. The kit comes with fine scale spacers so the question was, leave the chassis as intended and space the wheels with washers or widen the chassis, I took the latter as the rear end of the tender is very open and there is a chance the inner chassis will be seen, more so if fine scale spaced with S7 wheels.
I also slotted the frames to take Slaters insulated hornblocks, the idea being to use split axles for current collection, however, due to the exterior frame width and very limited clearances, maxing the axle live and running the risk of the hub touching said frame, I may opt for light wipers on the wheel rim, there's more than enough space in the tender to apply long lightly sprung ones to minimise friction.
I do intend to use CSB, again in a very fundamental and crude way, the CSB wire will just pass over the horn block, yes I know it'll touch each corner as it compresses and make a double contact point, but I think it'll still work, if not it'll be back to the original plan of a small handrail knob attached to the top of the plastic block and single point fulcrums. A photo will be forthcoming, once I get to that stage.
The spacers were soldered to the frames and then basically split down the middle, two small pieces of L brass were then soldered into place to check spacings, full width 20thou spacers will then be soldered under the split spacers to allow for fixings and making it all a little more rigid.
The current frames are 28.5 mm wide add in the plastic ridge on the horn block (1mm for each) your left with ±0.4mm side play, this may be too much and I may add 0.1/2mm washers to limit this, just depends how it goes through the point work at Love Lane. At ±0.4mm it is almost certain the wheel hubs are going to touch the exterior frames so I may have to open them out to accept the hub side play, or skim the hub....I'm hoping not to go down the latter route. If I go with wipers then it wont matter if the hubs touch as they'll be insulated.
The next problem will be the brake blocks, each side has a double pull rod that flanks the wheels, there is a high chance the pull rods will touch the rims with the above side play tolerances and if the etched brake shoes or cast replacements are used, will almost certainly short out, so plastic or resin alternatives will have to be sourced/made. I'm sure someone here already found some plastic brake shoes, but I've not found that post as yet.
Excuse the Stanier tender wheels, the correct ones have not arrived, probably because I haven't ordered them yet
I also slotted the frames to take Slaters insulated hornblocks, the idea being to use split axles for current collection, however, due to the exterior frame width and very limited clearances, maxing the axle live and running the risk of the hub touching said frame, I may opt for light wipers on the wheel rim, there's more than enough space in the tender to apply long lightly sprung ones to minimise friction.
I do intend to use CSB, again in a very fundamental and crude way, the CSB wire will just pass over the horn block, yes I know it'll touch each corner as it compresses and make a double contact point, but I think it'll still work, if not it'll be back to the original plan of a small handrail knob attached to the top of the plastic block and single point fulcrums. A photo will be forthcoming, once I get to that stage.
The spacers were soldered to the frames and then basically split down the middle, two small pieces of L brass were then soldered into place to check spacings, full width 20thou spacers will then be soldered under the split spacers to allow for fixings and making it all a little more rigid.
The current frames are 28.5 mm wide add in the plastic ridge on the horn block (1mm for each) your left with ±0.4mm side play, this may be too much and I may add 0.1/2mm washers to limit this, just depends how it goes through the point work at Love Lane. At ±0.4mm it is almost certain the wheel hubs are going to touch the exterior frames so I may have to open them out to accept the hub side play, or skim the hub....I'm hoping not to go down the latter route. If I go with wipers then it wont matter if the hubs touch as they'll be insulated.
The next problem will be the brake blocks, each side has a double pull rod that flanks the wheels, there is a high chance the pull rods will touch the rims with the above side play tolerances and if the etched brake shoes or cast replacements are used, will almost certainly short out, so plastic or resin alternatives will have to be sourced/made. I'm sure someone here already found some plastic brake shoes, but I've not found that post as yet.
Excuse the Stanier tender wheels, the correct ones have not arrived, probably because I haven't ordered them yet
Len Cattley
Western Thunderer
Hi Mick, "The next problem will be the brake blocks, each side has a double pull rod that flanks the wheels, there is a high chance the pull rods will touch the rims with the above side play tolerances and if the etched brake shoes or cast replacements are used, will almost certainly short out, so plastic or resin alternatives will have to be sourced/made. I'm sure someone here already found some plastic brake shoes, but I've not found that post as yet."Of the brake blocks ask Simon Thomson (of this parish) he can make a resin copy of them (for a small fee) all he needs is is a 3D scan of them with the measurements.
Len
Len
mickoo
Western Thunderer
Len, Simon cheers,
The problem is a littler more complex, the current hangers with blocks etched on are two thicknesses of 0.7mm back to back, giving a total of 1.4 mm thick brake shoes, the real tender shoes are tread width of at best 3.0mm, otherwise they will look too thin between the pull rods.
The solution will be to sandwich some appropriate thickness Plasticard between the shoes to 'fatten' them up, the top part of the etched lever will be cut away resulting in the Plasticard forming the top pivot and isolating from the frame. Thin brass rod will pass through the etched shoe pivot and Plasticard to replicate the fixing bolt and the same at the lower pivot; which will also need some brass tube (2.0mm dia) between the pull rods which are 4.5-4.75mm apart (depends on final side play in the axles) to replicate the lower bushing.
All a bit of a faff but should make the brake gear look more chunky and prototypical and unlike the loco the tender shoes and hangers are not seen for the majority of their length above the shoe pivot point.
Pictures latter if it all works out
The problem is a littler more complex, the current hangers with blocks etched on are two thicknesses of 0.7mm back to back, giving a total of 1.4 mm thick brake shoes, the real tender shoes are tread width of at best 3.0mm, otherwise they will look too thin between the pull rods.
The solution will be to sandwich some appropriate thickness Plasticard between the shoes to 'fatten' them up, the top part of the etched lever will be cut away resulting in the Plasticard forming the top pivot and isolating from the frame. Thin brass rod will pass through the etched shoe pivot and Plasticard to replicate the fixing bolt and the same at the lower pivot; which will also need some brass tube (2.0mm dia) between the pull rods which are 4.5-4.75mm apart (depends on final side play in the axles) to replicate the lower bushing.
All a bit of a faff but should make the brake gear look more chunky and prototypical and unlike the loco the tender shoes and hangers are not seen for the majority of their length above the shoe pivot point.
Pictures latter if it all works out
mickoo
Western Thunderer
On to the chassis, fitted the CSB and added extra spacer supports, which allow the fixing holes to be re-drilled.
I've just used the same CSB wire as the locos and due to the shorter distance between axles it's too firm so some smaller gauge will soften it up, there's no math involved, just by eye and feel, the centre axles have less pressure than the outers and it all feels level and smooth.
Anyway the pictures and notes, the model is not designed for S7 and there are a few pitfalls to catch the unwary, or put another way, next time I'd do things a little different
First up up, an overall 'dead bug' view
Of importance here are the two additional horns marked in red on the inner chassis, these are for the brake lay shaft (green), that's fine but when you add it the end bearings will not line up with the outer frames; so they have to go. The lay shaft will be beefed up and fixed to the outer frames, the cut away inner chassis will then 'slide' in under that part of the brake gear....it'll become clear as I progress...I hope
Another 'dead bug' view
The kit footplate comes with two half relieved etched slots in the base, these are for the outer frames to fit into, the inner one is scale width, the outer one the preferred 'tolerance' width. The inner one would be fine with finescale wheels but all but touches the rims in S7, let alone allowances for Slaters extended hubs; I opted to go just outside scale width so there's a gnats whisker clearance between the frames and Slaters hubs. One other part missing in the kit are the tank support flange webs, the flanges are there but no web that would be on the bottom of the footplate. Not an issue if viewing the model in normal 'gods eye' view but I like to view at ground level or just slightly lower, they are only thin plates but they put 'lumps' in the right place when viewing the model. I didn't bother with this model but next time will get some etched up. I'd also flood fill all the writing underneath as well.
And for the sake of completeness a ¾ view, only because it's sunny and it'd be a waste to bin the image LOL
There's still the air tank to go in and other sundry details.
The inner chassis
Of note are the CSB mounting points, just simple 1mm tube, certainly too large a bore and I'll be getting some smaller Dia for future projects but it does make it easier to thread the wire through and once loaded the wire only rests on the upper part of the tube so in reality the dia makes no difference. The Slaters insulated hornblock just rests on the underside of the view, no fancy pivot points, the pivots are the outer corners of the block, if I get overly bothered by that I'll just dome the top of the horn block to a radius smaller than that of the bent wire, maybe I'll do a couple....just because I can.
Same view but upside down, of note here is that the etched frame is different depths at the outer ends, so to make the pivot point the same height I added a small scrap piece of etch and soldered the tub to that to make them all the same height, oddly the front end turned out slightly lower (toward the rail) and thus the wire is bent downward slightly, this make the front marginally stiffer, which is what I wanted, by accident, not design I hasten to add
Side view of CSB arrangement
Close up of one axle and CSB arrangement.
Finally, given the above text at the beginning about the frame widths, it turns out that the footplate holes for the wheels are wrong as well
I did try the wheels first but figured...wrongly... that they'd probably not get this high, they do so I need to open the sides out a little to clear S7 widths. More important are the bits ahead of the front axle (and behind the rear axle) that need to be removed, the gauge makes no issue here, be it S7 or finescale there's a chance your wheel rims will short out here if using any form of suspension and even with fixed suspension you may come a cropper with fine scale rims which by nature are larger. Part of the problem I suspect is that the kit may have been designed for the correct 4' 2" wheels where as Slaters only offer 4' 3" ?
One other missive is the front axle alignment, despite laminating the frames and cutting the axle box slots in one go and assembling the frames square the front axle looks skewiff, part of it is the camera angle and lens but there is a small twist that is just measurable, not sure how to counter that, or if it's even worth the bother, the rest of the axle look much squarer so no idea how that one came out like that despite all being cut the exact same time and together.
Anyway, off to make some more brass swarf and filings accompanied by some finest light ale Of choice in the fridge are Spitfire, Hobgoblin or Bishops Finger, golly gosh, I may just push the boat out and have one of each!
I've just used the same CSB wire as the locos and due to the shorter distance between axles it's too firm so some smaller gauge will soften it up, there's no math involved, just by eye and feel, the centre axles have less pressure than the outers and it all feels level and smooth.
Anyway the pictures and notes, the model is not designed for S7 and there are a few pitfalls to catch the unwary, or put another way, next time I'd do things a little different
First up up, an overall 'dead bug' view
Of importance here are the two additional horns marked in red on the inner chassis, these are for the brake lay shaft (green), that's fine but when you add it the end bearings will not line up with the outer frames; so they have to go. The lay shaft will be beefed up and fixed to the outer frames, the cut away inner chassis will then 'slide' in under that part of the brake gear....it'll become clear as I progress...I hope
Another 'dead bug' view
The kit footplate comes with two half relieved etched slots in the base, these are for the outer frames to fit into, the inner one is scale width, the outer one the preferred 'tolerance' width. The inner one would be fine with finescale wheels but all but touches the rims in S7, let alone allowances for Slaters extended hubs; I opted to go just outside scale width so there's a gnats whisker clearance between the frames and Slaters hubs. One other part missing in the kit are the tank support flange webs, the flanges are there but no web that would be on the bottom of the footplate. Not an issue if viewing the model in normal 'gods eye' view but I like to view at ground level or just slightly lower, they are only thin plates but they put 'lumps' in the right place when viewing the model. I didn't bother with this model but next time will get some etched up. I'd also flood fill all the writing underneath as well.
And for the sake of completeness a ¾ view, only because it's sunny and it'd be a waste to bin the image LOL
There's still the air tank to go in and other sundry details.
The inner chassis
Of note are the CSB mounting points, just simple 1mm tube, certainly too large a bore and I'll be getting some smaller Dia for future projects but it does make it easier to thread the wire through and once loaded the wire only rests on the upper part of the tube so in reality the dia makes no difference. The Slaters insulated hornblock just rests on the underside of the view, no fancy pivot points, the pivots are the outer corners of the block, if I get overly bothered by that I'll just dome the top of the horn block to a radius smaller than that of the bent wire, maybe I'll do a couple....just because I can.
Same view but upside down, of note here is that the etched frame is different depths at the outer ends, so to make the pivot point the same height I added a small scrap piece of etch and soldered the tub to that to make them all the same height, oddly the front end turned out slightly lower (toward the rail) and thus the wire is bent downward slightly, this make the front marginally stiffer, which is what I wanted, by accident, not design I hasten to add
Side view of CSB arrangement
Close up of one axle and CSB arrangement.
Finally, given the above text at the beginning about the frame widths, it turns out that the footplate holes for the wheels are wrong as well
I did try the wheels first but figured...wrongly... that they'd probably not get this high, they do so I need to open the sides out a little to clear S7 widths. More important are the bits ahead of the front axle (and behind the rear axle) that need to be removed, the gauge makes no issue here, be it S7 or finescale there's a chance your wheel rims will short out here if using any form of suspension and even with fixed suspension you may come a cropper with fine scale rims which by nature are larger. Part of the problem I suspect is that the kit may have been designed for the correct 4' 2" wheels where as Slaters only offer 4' 3" ?
One other missive is the front axle alignment, despite laminating the frames and cutting the axle box slots in one go and assembling the frames square the front axle looks skewiff, part of it is the camera angle and lens but there is a small twist that is just measurable, not sure how to counter that, or if it's even worth the bother, the rest of the axle look much squarer so no idea how that one came out like that despite all being cut the exact same time and together.
Anyway, off to make some more brass swarf and filings accompanied by some finest light ale
Of choice in the fridge are Spitfire, Hobgoblin or Bishops Finger, golly gosh, I may just push the boat out and have one of each!
mickoo
Western Thunderer
JB, that'd work for the shoe but not the pull rods, these are the important parts that will cause the most issues.
Unlike other tenders the LNER 8 wheel tender has pull rods each side of the wheel, with the side play there is a chance that the rim will short out on the pull rod, so the rods and brake shoes/hangers all need to be insulated from the frame work.
Sorry for the dodgy pictures, of all the pictures I took, I didn't take any of this part of the tenders
it's not as though LNER locos are a new interest bubble for me as I already had the Finney kit and a list of Pacific's in my wish list when I took these!
Unlike other tenders the LNER 8 wheel tender has pull rods each side of the wheel, with the side play there is a chance that the rim will short out on the pull rod, so the rods and brake shoes/hangers all need to be insulated from the frame work.
Sorry for the dodgy pictures, of all the pictures I took, I didn't take any of this part of the tenders
it's not as though LNER locos are a new interest bubble for me as I already had the Finney kit and a list of Pacific's in my wish list when I took these!
mickoo
Western Thunderer
I didn't actually achieve what I set out to do on Sunday, except the ale drinking, that all went to plan though I did trim the inside of the footplate to clear the wheels and then decided on a whim to finish cleaning and rebuilding my C3 lathe (18 months after I started) and then decide to try some S7 wheel turning on a sacrificial wheel, well it went so well I ended up doing all the current spoked ones temporarily fitted to the A1 tender.
The thinning of the wheels has had a pleasant side effect in that the overall hub measurement is reduced by 0.5 mm, which means more tolerance for side play between the outer frames. The exercise also showed that no matter how flat or straight a wobbly wheel is mounted in the lathe, it still ends up wobbly on the axle, I've deduced that the issue lies with the brass hub fitting and basically your pretty much stuck with it as far as I can tell
I'd love to show pictures but frankly the only difference is that they are now more shiny, well a little thinner and a smaller flange of course LOL, but it was jolly good fun and the method was how shall we say...very tin plate, using only a spare finescale axle and the retaining screw with the wheel mounted backward but the wheels are round and true so it seems to work well, the proof of the pudding will be a run through Love Lane point work in a few weeks time
though I did trim the inside of the footplate to clear the wheels and then decided on a whim to finish cleaning and rebuilding my C3 lathe (18 months after I started) and then decide to try some S7 wheel turning on a sacrificial wheel, well it went so well I ended up doing all the current spoked ones temporarily fitted to the A1 tender.The thinning of the wheels has had a pleasant side effect in that the overall hub measurement is reduced by 0.5 mm, which means more tolerance for side play between the outer frames. The exercise also showed that no matter how flat or straight a wobbly wheel is mounted in the lathe, it still ends up wobbly on the axle, I've deduced that the issue lies with the brass hub fitting and basically your pretty much stuck with it as far as I can tell
I'd love to show pictures but frankly the only difference is that they are now more shiny, well a little thinner and a smaller flange of course LOL, but it was jolly good fun and the method was how shall we say...very tin plate, using only a spare finescale axle and the retaining screw with the wheel mounted backward but the wheels are round and true so it seems to work well, the proof of the pudding will be a run through Love Lane point work in a few weeks time