gwrfan
Part of the e-furniture
Posts: 456
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Post by gwrfan on Mar 31, 2019 20:26:57 GMT
Hi All,
After a considerable break I am again looking at my B1 'Springbok'. Martin Evans says to use 18 gauge (1.2mm) Black Mild Steel for the construction of the ashpan. I am having difficulty in finding this material and wondered what others have used? I have lots of 1.2mm brass sheet. Thanks for your suggestions.
Geoff
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Post by chris vine on Mar 31, 2019 22:10:00 GMT
Hi Geoff,
I wonder if brass might melt. In only say that because i made a stainless ashpan and the silver solder on the edges melted!!
Chris.
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Post by ettingtonliam on Mar 31, 2019 22:53:09 GMT
I got some 1.5mm galvanised sheet from my local sheet metal company. If black sheet is a problem, I don't see why galvanised shouldn't work, unless the design calls for it to be silver soldered. The ashpan for my open fire is galvanised!
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dscott
Elder Statesman
Posts: 2,437
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Post by dscott on Apr 1, 2019 5:01:33 GMT
Just do not get it too hot... Do not breath if you see white smoke appearing from your ashpan area! When welding the stuff you have to grind it away first! I used Copper and embossed rivets into it on the Terrier, it looks rusty in certain light. David.
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Post by ettingtonliam on Apr 1, 2019 5:37:13 GMT
it shouldn't be a problem, as I say, the ashpan of my open fire is galvanised and I've never had white smoke coming from it! When the original rusted through after 20 years, I made a replacement by bending and rivetting.
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stevep
Elder Statesman
Posts: 1,070
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Post by stevep on Apr 1, 2019 7:33:27 GMT
Nice to see you back again Geoff.
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gwrfan
Part of the e-furniture
Posts: 456
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Post by gwrfan on Apr 1, 2019 7:54:12 GMT
Nice to see you back again Geoff. Thanks Steve, and the others for suggestions.
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Post by Deleted on Apr 1, 2019 8:25:28 GMT
Hi Geoff
I wouldn't use brass for the reason Chris states, if it doesn't melt per se, it most certainly will deform, I wouldn't see it lasting very long. If it's of any help Don's drawing for 'Doncaster's'ashpan stipulate 1.6mm stainless steel. I plan to weld mine when I get to it, hopefully, in the not too distant future.
Cheers
Pete
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gwrfan
Part of the e-furniture
Posts: 456
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Post by gwrfan on Apr 1, 2019 8:35:47 GMT
Hi Geoff I wouldn't use brass for the reason Chris states, if it doesn't melt per se, it most certainly will deform, I wouldn't see it lasting very long. If it's of any help Don's drawing for 'Doncaster's'ashpan stipulate 1.6mm stainless steel. I plan to weld mine when I get to it, hopefully, in the not too distant future. Cheers Pete Thanks for this Pete. I thought the brass wouldn't be much use, and I have found galvanised steel plate available on Ebay, for not much cash, so I will probably go that way. I have no welding gear, so it'll be angle iron and rivits! Cheers. Geoff
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Post by 92220 on Apr 1, 2019 9:26:35 GMT
The biggest problem with using galvanised steel is that the first few times the fire is lit, you will have toxic fumes, from the zinc plate, coming off and being spread along with the smoke.
If you buy steel sheet from Ebay, it will be black steel unless it actually says 'bright'. I've been caught with this. A couple of times I've bought steel sheet from Ebay and it hasn't actually said that it is bright ansd when it has arrived it has been black. There is no reason why you can't use bright steel anyway. Black is possibly only suggested because it may be thought to not distort when being silversoldered, quite as much as bright steel, but it does still distort, as any metal will, with uneven heating. That just cannot be helped and would happen with any metal because distortion is all down to the different amounts of expansion due to the heat application. The hotter area will expand more than the cooler areas so will cause distortion. Doesn't matter whether it is black or bright, stainless or brass. Black might also be suggested because it is cheaper than bright steel sheet, though not a lot cheaper.
To minimise distortion, the whole assembly should be slowly brought up to temperature rather than just heating one area. That is easier said than done, but uneven heating is the main reason why assemblies distort during silversoldering.
Bob.
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Post by ettingtonliam on Apr 1, 2019 10:53:50 GMT
The biggest problem with using galvanised steel is that the first few times the fire is lit, you will have toxic fumes, from the zinc plate, coming off and being spread along with the smoke. If you buy steel sheet from Ebay, it will be black steel unless it actually says 'bright'. I've been caught with this. A couple of times I've bought steel sheet from Ebay and it hasn't actually said that it is bright ansd when it has arrived it has been black. There is no reason why you can't use bright steel anyway. Black is possibly only suggested because it may be thought to not distort when being silversoldered, quite as much as bright steel, but it does still distort, as any metal will, with uneven heating. That just cannot be helped and would happen with any metal because distortion is all down to the different amounts of expansion due to the heat application. The hotter area will expand more than the cooler areas so will cause distortion. Doesn't matter whether it is black or bright, stainless or brass. Black might also be suggested because it is cheaper than bright steel sheet, though not a lot cheaper. To minimise distortion, the whole assembly should be slowly brought up to temperature rather than just heating one area. That is easier said than done, but uneven heating is the main reason why assemblies distort during silversoldering. Bob.
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Post by ettingtonliam on Apr 1, 2019 10:58:37 GMT
i'd be surprised if you got the white fumes. It doesn't in my domestic ashpan, and thats about 1 1/2" below the fire, not much more than on a loco, plus the loco one is in fresh air, and the domestic one is in an enclosed space, so could well be hotter.
I've just looked on my Locomotion drawing and David Piddington specified 2.5mm BMS for the ashpan. Why so thick I have no idea.
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timb
Statesman
Posts: 511
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Post by timb on Apr 1, 2019 11:27:33 GMT
Vaporisation temperature for zinc is 906C melting point is 420C. I would have thought you would see the plating running off the steel before the fumes were encountered. You have to be careful with welding as the arc temperature is way above the vapourisation point of zinc to facilitate the melting of the weld.
Tim
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Post by delaplume on Apr 1, 2019 14:35:44 GMT
Hi All, After a considerable break I am again looking at my B1 'Springbok'. Martin Evans says to use 18 gauge (1.2mm) Black Mild Steel for the construction of the ashpan. I am having difficulty in finding this material and wondered what others have used? I have lots of 1.2mm brass sheet. Thanks for your suggestions. Geoff Hi Geoff........not heard from you in a while.....as per the others don't use brass as it's quite expensive for such a lowly task !! I use 16g steel....Black preferably as it's cheaper than Bright plus ashpans don't need to be built to a degree of accuracy that would call for Bright in the first place.. My neighbour is a steel fabricator and I have oodles of off-cuts ( at least that's what he calls them !!) plus a whole lot of my own collection from 40-odd years ago....... So, if you give me}--- a) The stock sizes that you need for a B1 b) Your postal address ( use the PM service on here for that ) I'll put together a "Goody Bag" for you and pop it in the post ...OK ?? Best regards Alan R
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Post by delaplume on Apr 1, 2019 15:46:07 GMT
Here's a 5"g ashpan and grate that I'm currently putting together for our Club loco ( a Hunslet )----- As I have full Oxy-Acetylene I braze all joints etc but in your case plain riveting will suffice......don't forget to incorporate a dump pin system if you can---it makes a world of difference when disposing at the end of a day's running....
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Post by 92220 on Apr 1, 2019 16:04:09 GMT
Vaporisation temperature for zinc is 906C melting point is 420C. I would have thought you would see the plating running off the steel before the fumes were encountered. You have to be careful with welding as the arc temperature is way above the vapourisation point of zinc to facilitate the melting of the weld. Tim Agreed Tim. I must admit to being over-cautious. I didn't actually read the OP properly either. It's an ashpan, that is being made, which doesn't get hot enough to be a problem. Firebars might be a different matter, but they tend to be made of stainless anyway. Bob.
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Tony K
Elder Statesman
Posts: 1,572
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Post by Tony K on Apr 2, 2019 8:16:35 GMT
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