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    Home made foundry question

    Brass shell casings are made of the appropriately named cartridge brass which is 70/30 Cu/Zn , it does require a slightly higher temperature for melting but should be easily attained in well designed home furnace. It is likely that the formation of zinc oxide on the thin metal caused the...
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    Tapping Question

    Your hole will only have about 4 threads , no room for a taper tap start , I would grind the tap right back flat and hand tap , the feel will be better and there is almost no chance of breaking the tap. What is the thread doing ? can the part be better designed ? Dan.
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    Milling a slot

    If the prototype frames were a timber sandwich , so to speak , why not make the model in the same way ? laser and high pressure water jet have become the norm now for cutting out steel loco frames , both are readily available and cheap here in the UK. Dan.
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    Foundry how to set a home use

    Visit my website www.unionsteammodels.co.uk where you will find many pictures of my home foundry. Dan.
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    Adding graduations to tailstock spindle

    What a nice first post , Xtroll would be a more suitable name.
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    Lathe (another discussion)

    A lathe for making model engine parts need not be very heavy to give suitable accuracy , and even relatively large machines can be moved with a little ingenuity. I have a Pultra lathe which is tiny yet capable of turning items from a few thou diameter up to almost 3 inches with repeatable...
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    First Boiler info

    Chuck I think there is some confusion here , the "gap" is where the bush enters the boiler tube and this can be as close as you like , i.e a 1/2" dia bush goes in a 1/2" dia hole . The gap between the flange and the tube doesn't count , and it will fill quite easily with solder. The secret to...
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    Heat treat rings

    A small kiln for heat treatment can be very simply made using a sheathed element either salvaged from a redundant storage heater or purchased new. Simply coil the element around a steel tube former and cover with fire cement. When the cement has set remove the former , end caps can be made from...
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    Flat Belt Reversing Mechanism

    Mortimer was that Churchill -Matrix ? Dan.
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    Turning square headed bolts

    I make dozens of 4BA square heads for my miniature quick change toolposts , I have a Pultra lathe with capstan turret and a coventry die head. Email me a drawing and I will quote if you like . Dan.
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    Cheap soft jaws for a 3 jaw chuck

    Superglue ,Loctite , Araldite all work if used correctly and a little heat removes all!
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    Carbon Fiber Roving and Carbon Fiber Powder Comparison in Strenght for Engine Casing

    Not sure of the terminology , what do you mean by roving ? By strong presumably you mean tensile strength ? The tensile strength of carbon fibre is in the strength of the strand not the supporting resin. The use of fillers can modify many of the resin composite properties such as density ...
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    HSS Lathe form tool shaping

    Mike surely you have a bench grinder ? I can't imagine a home machine shop without one. You grind all your HSS lathe tools by hand and finish if you need to using a diamond hone. For more complex form tools use carbon tool steel , machine or file the desired shape then harden and temper...
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    Ceramic Shell Casting Steel

    It would be helpful if you said where you are located, not much use me giving you a contact in the UK if you are elsewhere. It is very unlikely that a commercial foundry will risk burn-out on a printed plastic pattern. Ceramic shell is very brittle and cannot withstand much expansion of the...
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    Garage Sale Find

    What did you make your key from ? Will it harden and temper ? If not you will find it wears out very quickly. Trueing a job to within a thou or so often requires more force than a 1/4" square mild steel can take. This has been my experience with independent 4 jaws Dan.
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    ratios for cylinder volumes in compound engines

    The ratio of cylinder diameters is not the only design criteria , steam cut-off is also critical for a balanced engine. You may find this page useful http://www.1902encyclopedia.com/S/STE/steam-engine-06.html Dan.
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    ratios for cylinder volumes in compound engines

    Asking for information requires no input from you , just the goodwill of others who have done the work before you . This approach can hardly be described as "research". Follow Charles' advice and read some of the available literature , you may or may not obtain the knowledge that you seek , but...
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    ratios for cylinder volumes in compound engines

    The relationship of cylinders sizes in compound steam engines has been well documented for more than 100 years , it is also documented that condensers do not work efficiently at model scales . some research will provide all the information you might require.
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    Cad cam alternatives

    Have a look at 2D/3DViaCad from Punch Software . I came across it several years ago whilst searching for a Mac 3D cad application. It is amazing value for money , a lifelong license is about $100 but you can try it free for 30 days. It is very easy to use for 2D or 3D design and you don't need...
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    Brass piston and cylinder problem

    You beat me to it Zakman , Mamod's always used brass cylinders with brass pistons although these had large clearance and run on wet steam , see how they run with a squirt of oil lol! My own high pressure engines use gun-metal pistons in cast brass cylinders but I do use a viton ring. Dan.
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