Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 4, 2019 12:16:16 GMT
I thought it was about time I tried to fit this to the boiler and decide what I'm doing with the barrel cladding. This has been machined with a 2.5mm 2-flute carbide cutter, almost all the way through.  20170828_151853 by Roger Froud, on Flickr ... you can see the now familiar witness marks on the back.  20170828_151950 by Roger Froud, on Flickr I had to cut a slot where the butt strap goes else it wouldn't go over the safety valve bush. I also had to file away quite a lot near the bottom where it's clearly not as round as it should be. Now I need to decide whether the 0.5mm thick Brass sheet I intend to attach as a collar will be strong enough. The idea was to let it pull down onto the throatplate flange, but I'm not sure that's going to work. It may have to be a little thicker.  20170828_170149 by Roger Froud, on Flickr Hi Roger Sorry to take you back 18 months or so, but can you remember what thickness of brass sheet you used for the cladding throat plate in these pictures? In the photo it looks heavier than the 0.5mm you used elsewhere. I'm thinking that as a component it is nearly all air, so likely to be a bit floppy in thin stuff -? David Adams doesn't directly specify a thickness for this item on the Paddington drawings, though he suggests 0.015" (brass) for the remainder of the cladding, which is only ¾ the thickness of the steel you used in 1" scale. Of course, thinner material makes the metal bashing easier, and on a 15xx most of the cladding is hidden anyway. Can anyone advise me? Best regards Gary |
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Post by Roger on Feb 4, 2019 12:30:43 GMT
Hi Roger Sorry to take you back 18 months or so, but can you remember what thickness of brass sheet you used for the cladding throat plate in these pictures? In the photo it looks heavier than the 0.5mm you used elsewhere. I'm thinking that as a component it is nearly all air, so likely to be a bit floppy in thin stuff -? David Adams doesn't directly specify a thickness for this item on the Paddington drawings, though he suggests 0.015" (brass) for the remainder of the cladding, which is only ¾ the thickness of the steel you used in 1" scale. Of course, thinner material makes the metal bashing easier, and on a 15xx most of the cladding is hidden anyway. Can anyone advise me? Best regards Gary Hi Gary, The Brass is 2mm thick on the throatplate. I disagree that it's easier to form the shape from thin material, it's far more likely to buckle and it gets marked much more easily. The material can be compressed into itself much easier where the corners need to lose material if it's thick. I think I only had to anneal the Brass about six times in all to form that shape. If I did it again, I'd make the throatplate flanges longer and machine them to give a better register for the firebox side cladding, and more depth of thread for the fixings. The thin flanged part is 0.5mm thick, and that's Silver Soldered on. Ideally that would have been thicker, but it's possible to do it step by step rather than attempting to Silver Solder it in one operation. |
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Post by yorkshireman on Feb 4, 2019 16:07:12 GMT
Hallo Roger
The boiler of the original loco is actually a tapered Belpaire Boiler.
You should consider this fact too...
Regards
Johannes
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Post by Roger on Feb 4, 2019 16:13:29 GMT
Hallo Roger The boiler of the original loco is actually a tapered Belpaire Boiler. You should consider this fact too... Regards Johannes Indeed, the thin skirt that's Silver Soldered to the inside of the throatplate cladding is slightly tapered so that the tapered boiler cladding sits down on it nicely. |
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 4, 2019 16:19:12 GMT
Hi Roger Sorry to take you back 18 months or so, but can you remember what thickness of brass sheet you used for the cladding throat plate in these pictures? In the photo it looks heavier than the 0.5mm you used elsewhere. I'm thinking that as a component it is nearly all air, so likely to be a bit floppy in thin stuff -? David Adams doesn't directly specify a thickness for this item on the Paddington drawings, though he suggests 0.015" (brass) for the remainder of the cladding, which is only ¾ the thickness of the steel you used in 1" scale. Of course, thinner material makes the metal bashing easier, and on a 15xx most of the cladding is hidden anyway. Can anyone advise me? Best regards Gary Hi Gary, The Brass is 2mm thick on the throatplate. I disagree that it's easier to form the shape from thin material, it's far more likely to buckle and it gets marked much more easily. The material can be compressed into itself much easier where the corners need to lose material if it's thick. I think I only had to anneal the Brass about six times in all to form that shape. If I did it again, I'd make the throatplate flanges longer and machine them to give a better register for the firebox side cladding, and more depth of thread for the fixings. The thin flanged part is 0.5mm thick, and that's Silver Soldered on. Ideally that would have been thicker, but it's possible to do it step by step rather than attempting to Silver Solder it in one operation. Thanks Roger, that's very helpful advice for this rookie metal basher. I suspect making the former is going to be the worst part of the job; it needs to be about 30mm thick to get the contours in Paddington size! -Gary |
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Post by Roger on Feb 4, 2019 16:33:01 GMT
Hi Gary, The Brass is 2mm thick on the throatplate. I disagree that it's easier to form the shape from thin material, it's far more likely to buckle and it gets marked much more easily. The material can be compressed into itself much easier where the corners need to lose material if it's thick. I think I only had to anneal the Brass about six times in all to form that shape. If I did it again, I'd make the throatplate flanges longer and machine them to give a better register for the firebox side cladding, and more depth of thread for the fixings. The thin flanged part is 0.5mm thick, and that's Silver Soldered on. Ideally that would have been thicker, but it's possible to do it step by step rather than attempting to Silver Solder it in one operation. Thanks Roger, that's very helpful advice for this rookie metal basher. I suspect making the former is going to be the worst part of the job; it needs to be about 30mm thick to get the contours in Paddington size! -Gary My advice would be to make a chunky holder, say 50mm x 50mm x 150mm that you can bolt to the underside of the former and locate with dowels on a standard pattern. That makes it dead easy to hold in the mill vice so you can machine all of the way round, and also for holding in the bench vice for the forming operation. I made mine right at the start and it was used for every flanging plate I made for the boiler. It's very little effort and you get a lot of value out of it. Since you have CNC, it's easy to machine the former and you can add the corner radii too, so there's next to no hard manual labour. |
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Post by Roger on Feb 4, 2019 22:10:48 GMT
I decided to make a different sort of former to help get the bend in the right place on the shackles.  20190204_183112 by Anne Froud, on Flickr Rather than bend it cold, I thought I'd smother it in flux and bend it hot.  20190204_191020 by Anne Froud, on Flickr This is the first step, followed by...  20190204_191240 by Anne Froud, on Flickr ... this to get it right round.  20190204_194632 by Anne Froud, on Flickr Obviously this still needed to be fitted over the pivot ends, after which it was softened again.  20190204_201254 by Anne Froud, on Flickr I forgot that this piece needed to be threaded through the drawbar, so it had to be opened up, softened again and refitted. Anyway, after much messing about, this is the result.  20190204_215126 by Anne Froud, on Flickr |
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JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,986
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Post by JonL on Feb 4, 2019 22:16:08 GMT
That has come out beautifully.
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 5, 2019 1:23:18 GMT
Thanks Roger, that's very helpful advice for this rookie metal basher. I suspect making the former is going to be the worst part of the job; it needs to be about 30mm thick to get the contours in Paddington size! -Gary My advice would be to make a chunky holder, say 50mm x 50mm x 150mm that you can bolt to the underside of the former and locate with dowels on a standard pattern. That makes it dead easy to hold in the mill vice so you can machine all of the way round, and also for holding in the bench vice for the forming operation. I made mine right at the start and it was used for every flanging plate I made for the boiler. It's very little effort and you get a lot of value out of it. Since you have CNC, it's easy to machine the former and you can add the corner radii too, so there's next to no hard manual labour. Ah alas, I have CAD and DRO but no CNC, it will have to be the old-fashioned way :-( But the holder for the machine vice, that makes perfect sense. Thanks Roger -Gary |
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Post by Oily Rag on Feb 5, 2019 6:34:16 GMT
Stone the crows, Roger there are some lovely gems in these last few pages.
A lot to be absorbed and recalled when I require.
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Post by Roger on Feb 5, 2019 8:10:20 GMT
My advice would be to make a chunky holder, say 50mm x 50mm x 150mm that you can bolt to the underside of the former and locate with dowels on a standard pattern. That makes it dead easy to hold in the mill vice so you can machine all of the way round, and also for holding in the bench vice for the forming operation. I made mine right at the start and it was used for every flanging plate I made for the boiler. It's very little effort and you get a lot of value out of it. Since you have CNC, it's easy to machine the former and you can add the corner radii too, so there's next to no hard manual labour. Ah alas, I have CAD and DRO but no CNC, it will have to be the old-fashioned way :-( But the holder for the machine vice, that makes perfect sense. Thanks Roger -Gary Apologies Gary, I'm mixing you up with someone else. If you're using Fusion360 or have a CAM package built in to you CAD, you might consider using the Manual CNC method described in another thread. I presume the DRO on the mill has linear scales so backlash won't be an issue. You might have to machine the former in two stages though so you can get all around it. You'd need a pretty big mill to cover the complete profile. At lease with a mount with dowels you could flip it over and machine the second half from the other side. |
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 5, 2019 20:46:55 GMT
Ah alas, I have CAD and DRO but no CNC, it will have to be the old-fashioned way :-( But the holder for the machine vice, that makes perfect sense. Thanks Roger -Gary Apologies Gary, I'm mixing you up with someone else. If you're using Fusion360 or have a CAM package built in to you CAD, you might consider using the Manual CNC method described in another thread. I presume the DRO on the mill has linear scales so backlash won't be an issue. You might have to machine the former in two stages though so you can get all around it. You'd need a pretty big mill to cover the complete profile. At lease with a mount with dowels you could flip it over and machine the second half from the other side. Sorry to take you off at a complete tangent Roger, but no, I mean really old-fashioned. The throatplate cleading former for Paddington is BIG, 230mm x 240mm and about 30mm thick, so it will be bandsaw and plane most likely, but at least I can mark it out from CAD by printing onto self adhesive film. First I have to find a suitable close-grained material- don't fancy filing it out of steel ! I'm thinking hardwood worktop offcut, but I don't know how much clouting it will take without bruising. Many thanks for taking the time to make suggestions; now get back to your couplings! -Gary |
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Post by delaplume on Feb 5, 2019 20:57:51 GMT
Hello everyone--------Gary, just a thought but do Reeves have some formers that you can borrow / rent ??
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Post by Roger on Feb 5, 2019 21:49:16 GMT
Apologies Gary, I'm mixing you up with someone else. If you're using Fusion360 or have a CAM package built in to you CAD, you might consider using the Manual CNC method described in another thread. I presume the DRO on the mill has linear scales so backlash won't be an issue. You might have to machine the former in two stages though so you can get all around it. You'd need a pretty big mill to cover the complete profile. At lease with a mount with dowels you could flip it over and machine the second half from the other side. Sorry to take you off at a complete tangent Roger, but no, I mean really old-fashioned. The throatplate cleading former for Paddington is BIG, 230mm x 240mm and about 30mm thick, so it will be bandsaw and plane most likely, but at least I can mark it out from CAD by printing onto self adhesive film. First I have to find a suitable close-grained material- don't fancy filing it out of steel ! I'm thinking hardwood worktop offcut, but I don't know how much clouting it will take without bruising. Many thanks for taking the time to make suggestions; now get back to your couplings! -Gary No problem, it's all interesting. I wonder if the former could be MDF? That's pretty dense and perhaps varnish soaked into it would make it harder? The main thing with forming the brass is not to go far with each round of the mallet. Just one good go round and then anneal it. If it moves a little, you can move it as far as you want with enough passes. I would stick to dead blow mallets or nylon ones. Copper or aluminium mallets will mark it and will take a lot of tidying up. |
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Post by delaplume on Feb 5, 2019 23:14:07 GMT
Hi Roger, Yes, MDF has already been used by others and quite successfully too....Traditional rolled hide mallets are best IMHO... Have a look at this}------ youtu.be/PSDJhdcNAew ------- |
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Post by ettingtonliam on Feb 5, 2019 23:58:33 GMT
Hello everyone--------Gary, just a thought but do Reeves have some formers that you can borrow / rent ?? Borrow? Borrow? What world are you in? Seriously though, I doubt it, they've been selling off their formers for some time now. |
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Gary L
Elder Statesman
Posts: 1,208
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Post by Gary L on Feb 6, 2019 0:01:04 GMT
Hello everyone--------Gary, just a thought but do Reeves have some formers that you can borrow / rent ?? Alan -Thanks for that suggestion; I hadn't thought of that! From a search through their website though it appears not. They are selling off their steel Paddington boiler formers at a suitably impressive price, but of course they will be too small. Also sadly the boiler I have inherited is like Speedy's; true to the drawings, but the firebox is a rather liberal interpretation of the prototype, so I have drawn some minor tweaks which I hope will improve the visual impression a little. Just as well a lot of it is out of sight. Roger -Many thanks for the MDF suggestion, I think that might be the answer... It comes in varying densities if I remember correctly, and I recall some of the heavier stuff is pretty tough. If I can track down some suitable offcuts, that might well do the trick. Also thanks for the suggestions on working the brass. I wish I hadn't already seen your results first though; I fear you might have set the bar too high! :-) Best wishes to all Gary |
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Post by delaplume on Feb 6, 2019 2:32:49 GMT
Hello everyone--------Gary, just a thought but do Reeves have some formers that you can borrow / rent ?? Borrow? Borrow? What world are you in? Seriously though, I doubt it, they've been selling off their formers for some time now. The world of the cash-strapped, mortgage-laden, child-blessed, "Domestic-Engineered" Model Engineer----LoL !! ( and that's on a good day !!) Yes, they have---haven't they ??........maybe they might have something left over ?? Fortune favours the Brave, etc---etc.. |
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dscott
Elder Statesman
Posts: 2,440
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Post by dscott on Feb 6, 2019 7:25:47 GMT
The Reeves formers are a source of amusement to me and others involved in Boiler Work?
YES for them to sell kits of THEIR DESIGN OF LOCOMOTIVES they need to keep these as the major
reason for buying a kit is to avoid making up a set of formers!!!!!
You simply buy everything from another company at a far better price.
I got to know Alec Farmer very well at Reeves and he said most had been tweaked to become
perfect for the boiler in question over the years!
On the Big Prairie the forward firebox flanged plate is double flanged to accept the boiler
barrel so needing several plates. Unfortunately you do need someone who knows what they are doing
in charge as supplying Simplex wheels for Jintys and Speedys is not on!!! These have a D section
instead of a curve at the back.
Blackgates have the correct wheels I checked with them!
In the advent of Laser and waterjet cutting your own set could be had quite cheaply!!!
For the Cash strapped, MDF and well annealed plates does well even for pressing smokebox doors round!
Done both and survived!
David and Lily. Up early for a Working Wednesday at the track! And borrow of MIG Welder!
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Post by Doug on Feb 6, 2019 7:53:04 GMT
Hello everyone--------Gary, just a thought but do Reeves have some formers that you can borrow / rent ?? Alan -Thanks for that suggestion; I hadn't thought of that! From a search through their website though it appears not. They are selling off their steel Paddington boiler formers at a suitably impressive price, but of course they will be too small. Also sadly the boiler I have inherited is like Speedy's; true to the drawings, but the firebox is a rather liberal interpretation of the prototype, so I have drawn some minor tweaks which I hope will improve the visual impression a little. Just as well a lot of it is out of sight. Roger -Many thanks for the MDF suggestion, I think that might be the answer... It comes in varying densities if I remember correctly, and I recall some of the heavier stuff is pretty tough. If I can track down some suitable offcuts, that might well do the trick. Also thanks for the suggestions on working the brass. I wish I hadn't already seen your results first though; I fear you might have set the bar too high! :-) Best wishes to all Gary Hi Gary I was given the tip to use model aircraft dope on MDF it hardens the surface significantly and makes it ideal for forming |
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