JonL
Elder Statesman
WWSME (Wiltshire)
Posts: 2,991
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Post by JonL on Jan 9, 2019 21:43:21 GMT
That looks beautifully engineered.
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Post by Deleted on Jan 9, 2019 21:54:19 GMT
looking great Brian, nice work sir...
Pete
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Post by David on Jan 10, 2019 22:00:44 GMT
Looks great Brian!
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Post by runner42 on Jan 22, 2019 21:40:36 GMT
Lovely Adelaide? Today another 40 degrees C, but tomorrow it's forecast 45 degrees C and that is a conservative estimate it could beat the all time record set in 1939 of 46.1 degrees C. So I am being kept out of the shed, where the temperature is higher than the outside temperature. So I can spend a little time in considering how I am going to overcome the cylinder procurement problem. Reeves will cost me over A$770 plus 10% GST and EJ Winter previously had similar castings for the locomotive Royal Engineer, but unfortunately don't have the casting pattern to get them recast. So unless someone can direct me to a cheaper source then fabrication is the answer. What I intend to do is obtain some hollowed LG2 gunmetal of approximate size machined to the cylinder bore and holder for the piston valve liner. mill flats on both and silver solder together and then fabricate the bolting face, etc from brass. The sketch shows the basic principle. Brian  cylinder sketch by Brian Leach, on Flickr |
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Post by Roger on Jan 23, 2019 14:39:08 GMT
Hi Brian,
Leaded Bronze is surprisingly cheap, that's what I ended up machining mine from. This is the quote for mine from Leeds Bronze....
We can offer you SAE660 3.17/32”dia (96.03mm) x 170mm length @ £86.25 with carriage @ £10.00 + vat
Personally I would forget about hollow bar, finding anything suitable is not easy, and it's probably not going to be worth designing around for what little cost advantage there might be. It's hard to see how you would get all of the materials cheaper than that quote. You do have to shop around though, there was quite a big difference in price between suppliers.
If you plan the machining around the main cylinder bore, including the holes in for the cylinder covers, you can make a mandrel and perhaps end supports so you can present it to the cutting tool in whatever orientation you choose.
In my opinion it's not a big deal to machine this from solid, at least you know there won't be any voids.
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Post by simplyloco on Jan 23, 2019 15:01:31 GMT
Hi Brian, SNIP Personally I would forget about hollow bar, finding anything suitable is not easy, and it's probably not going to be worth designing around for what little cost advantage there might be. It's hard to see how you would get all of the materials cheaper than that quote. SNIP Hi Roger I wouldn't dream of hacking through a 4" solid bar when I can get cored SAE 660 bronze! Even if the price is the same it's a lot less hassle...  John www.collegeengineering.co.uk/product-category/phosphor-bronze/phosphor-bronze-cored-bar/ |
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Lisa
Statesman
Posts: 806 
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Post by Lisa on Jan 23, 2019 16:17:04 GMT
An alternative option could be to make a set of patterns, then see if you can broker a deal with EJ Winter to sell them your patterns in return for cheaper castings.
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Post by Roger on Jan 23, 2019 19:14:21 GMT
Hi Brian, SNIP Personally I would forget about hollow bar, finding anything suitable is not easy, and it's probably not going to be worth designing around for what little cost advantage there might be. It's hard to see how you would get all of the materials cheaper than that quote. SNIP Hi Roger I wouldn't dream of hacking through a 4" solid bar when I can get cored SAE 660 bronze! Even if the price is the same it's a lot less hassle... John www.collegeengineering.co.uk/product-category/phosphor-bronze/phosphor-bronze-cored-bar/Yeah, but the hole for the cylinder bore wouldn't be in the middle if you machined the whole thing from solid, which is what I'm suggesting. |
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Post by simplyloco on Jan 23, 2019 20:04:58 GMT
Point taken: I hadn't read the previous!
John
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Post by ianholder on Jan 23, 2019 20:12:21 GMT
If it was me I would get a block of continuous cast iron and machine it out of that. You can get continuous cast cut to what ever size you want, you don't have the problem of blow holes and it machines very well, although you may look as if you have been down a coal mine afterwards. Square the block off to the outside dimensions of the cylinder block, bore the holes for the pistons and valves and use them to profile the outside of the block. You can do the fancy recesses round the cylinder and valve chamber but I don't think that is all that important in our sizes, regards Ian
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Post by runner42 on Jan 23, 2019 21:18:20 GMT
Hi Brian, Leaded Bronze is surprisingly cheap, that's what I ended up machining mine from. This is the quote for mine from Leeds Bronze.... We can offer you SAE660 3.17/32”dia (96.03mm) x 170mm length @ £86.25 with carriage @ £10.00 + vat Personally I would forget about hollow bar, finding anything suitable is not easy, and it's probably not going to be worth designing around for what little cost advantage there might be. It's hard to see how you would get all of the materials cheaper than that quote. You do have to shop around though, there was quite a big difference in price between suppliers. If you plan the machining around the main cylinder bore, including the holes in for the cylinder covers, you can make a mandrel and perhaps end supports so you can present it to the cutting tool in whatever orientation you choose. In my opinion it's not a big deal to machine this from solid, at least you know there won't be any voids. Hi Roger, the cost of non hollowed LG2 gunmetal rod from EJ Winter will cost me A$ 362 plus P&P, hollowed is price on application so if it is comparable to non hollowed I shall go for non hollowed. As you see the cost is less than half of the cost of castings from Reeves. The bolting face brass material is going to be under A$ 50 and another A$ 64 to make the cylinder end covers. I already have LG2 gunmetal to make the liners. An unexpected bonus from fabricating the cylinders is that it is easy to achieve the correct measurement for the offset of the piston valve liner to the cylinder and achieve parallelism of them. It is all predicated on the size of the flats machined on both. Both these features require careful setting up if using castings. Brian |
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Post by runner42 on Jan 23, 2019 21:21:10 GMT
An alternative option could be to make a set of patterns, then see if you can broker a deal with EJ Winter to sell them your patterns in return for cheaper castings. Hi Lisa, I wouldn't know how to go about making them. Brian |
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Post by runner42 on Jan 23, 2019 21:28:32 GMT
If it was me I would get a block of continuous cast iron and machine it out of that. You can get continuous cast cut to what ever size you want, you don't have the problem of blow holes and it machines very well, although you may look as if you have been down a coal mine afterwards. Square the block off to the outside dimensions of the cylinder block, bore the holes for the pistons and valves and use them to profile the outside of the block. You can do the fancy recesses round the cylinder and valve chamber but I don't think that is all that important in our sizes, regards Ian <iframe width="29.860000000000127" height="3.5600000000000023" style="position: absolute; width: 29.860000000000127px; height: 3.5600000000000023px; z-index: -9999; border-style: none;left: 15px; top: -5px;" id="MoatPxIOPT0_28716564" scrolling="no"></iframe> <iframe width="29.860000000000127" height="3.5600000000000023" style="position: absolute; width: 29.86px; height: 3.56px; z-index: -9999; border-style: none; left: 1427px; top: -5px;" id="MoatPxIOPT0_77261317" scrolling="no"></iframe> <iframe width="29.860000000000127" height="3.5600000000000023" style="position: absolute; width: 29.86px; height: 3.56px; z-index: -9999; border-style: none; left: 15px; top: 118px;" id="MoatPxIOPT0_42021142" scrolling="no"></iframe> <iframe width="29.860000000000127" height="3.5600000000000023" style="position: absolute; width: 29.86px; height: 3.56px; z-index: -9999; border-style: none; left: 1427px; top: 118px;" id="MoatPxIOPT0_76129179" scrolling="no"></iframe> Hi Ian, yes that is worth consideration, especially having seen a series of youtube videos from Mr Crispin where he does exactly that but using steel as the bulk material and cast iron liners for the cylinder bores and piston valve liner. Brian |
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oldnorton
Statesman
5" gauge LMS enthusiast
Posts: 727
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Post by oldnorton on Jan 25, 2019 14:09:51 GMT
Hi Brian
I like your idea of fabricating the cylinders, but it will be a lot of work. Sometimes a decision to buy what is available works out miles quicker and might only cost a bit more.
Why not use cast iron cylinders? Plus cast iron pistons and valve liners. All compatible metals that have been proven to run well together. Just take precautions to flush oil through at the end of steaming, and especially before a winter lay-up.
Reeves are doing a pair of cylinders plus front and rear main cylinder covers in cast iron for £207. I don't know what you have to add to get them shipped to Australia, but I guess you know.
Norm
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Post by Roger on Jan 25, 2019 15:07:23 GMT
Hi Brian I like your idea of fabricating the cylinders, but it will be a lot of work. Sometimes a decision to buy what is available works out miles quicker and might only cost a bit more. Why not use cast iron cylinders? Plus cast iron pistons and valve liners. All compatible metals that have been proven to run well together. Just take precautions to flush oil through at the end of steaming, and especially before a winter lay-up. Reeves are doing a pair of cylinders plus front and rear main cylinder covers in cast iron for £207. I don't know what you have to add to get them shipped to Australia, but I guess you know. Norm I agree that it's a lot of work. I think it's a lot less work to machine them from solid, whether that's from Cast Iron or Bronze. |
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Post by runner42 on Jan 26, 2019 4:54:11 GMT
Perhaps a casting can be obtained from EJ Winter not the Black 5 type but a Springbok or Fury casting maybe suitable, which can be adapted. The photo shows the Springbok and Fury castings which EJ Winter may be able to get cast in GM. The Fury casting appears to be the same as Royal Engineer which a SASMEE colleague used for his Black 5. If this works out I shall prefer to use this to the Black 5 casting because the method of construction of the liner doesn't require two internal bored slots in the casting (shown in red). These are more readily established in the liner which is an easier turning operation. The Fury casting length is 3 1/4" whereas the Black 5 is 3 5/16", generally there is more material in the casting for machining purposes so the 1/16" longer should not be a problem. We'll see. Brian  Composite cylinders by Brian Leach, on Flickr |
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Post by runner42 on Feb 1, 2019 6:29:55 GMT
It looks Springbok can be used as an alternative having enough material for machining, so EJ Winter is getting them cast in Gunmetal apparently all previous Springbok castings have used Cast Iron, I don't know if the pattern is produced for one particular material or if it is OK for any type. I have remade the radius rods from steel, Pete's use of HRPO steel doesn't appear to have better wear characteristics, but I maybe wrong. Anyway if I have to have another go then so be it. Brian.  Radius rods by Brian Leach, on Flickr |
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dscott
Elder Statesman
Posts: 2,440
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Post by dscott on Feb 1, 2019 7:50:31 GMT
Which came first The Class 2 or the Black Five as they both use the same cylinder so Blackgates not Reeves for Class 2 ones!
But by the time you have invested in a rotary table or some way of rotating your block Castings may come out cheaper!
Man with a Rotary table and a Universal Dividing head with Tailstock may take too long pondering which to use!!!
David and Lily. Snow preventing expedition to workshop today!!!
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Post by RGR 60130 on Feb 1, 2019 9:12:02 GMT
Brian,
Looking at the photo of radius rods they appear to be identical. Does the design not require a handed pair? Hopefully I'm missing something.
Regarding the cylinder pattern, it should be fine for cast iron or gunmetal. The difference in shrinkage will be neglegible.
Reg
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Post by Cro on Feb 1, 2019 10:00:14 GMT
Brian, Looking at the photo of radius rods they appear to be identical. Does the design not require a handed pair? Hopefully I'm missing something. Regarding the cylinder pattern, it should be fine for cast iron or gunmetal. The difference in shrinkage will be neglegible. Reg Two Photos, showing each side....I thought the same as you to start with. |
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