i think i can (noob steam engine builder questions)

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stevecobb76

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This whole post is troll food i know,:fan: but I have questions being a noob model steam engine builder.
i bough a small lathe about a month ago after seeing some model steam engines I knew I wanted to build one or 20. so i have been watching 500,000,000,000 youtube videos on model steam engines. i already do alot of welding and fabricating with steel.
and I have several plans and designs that i like but I am doing my own design so I can do my own eye candy & polishing & rivets too.
my plans right now are for a 2 cylinder 2 beam engine with 2 flywheels.
as far as steam engine metals:
what is the easiest / cheapest / best / readily available metals?
when i do my own bearing blocks, does copper on copper wear better / outlast brass on brass? or should I do some copper on brass combo?
aluminum?

and how about larger/thicker pieces or aluminum, brass, or copper? best sources?
assuming I wanted to fabricate a cylinder and a slide piston all in 1 solid chunk of brass/copper, could I silver solder 1" thick slabs to give me the size I need to machine out my parts? i.e. 2" bore x 6" stroke. I was just wondering about a piston sliding up and down past a solder joint and how that would wear.
also what are my options boring a hole this big in brass or copper or aluminum. maybe even a solid aluminum block with a brass or copper cylinder sleeve pressed in?

flywheel questions.. can you add something to lead while molten to make it harder when cast? I know how to work harden it, and I am set up to melt and pour lead now.

crankshaft options? i thought of stealing one from a weed eater or chainsaw engine? but thats kind of cheating.

any specific tools I might needs? special bits for boring? my lathe does not have a tailstock so i will have to use my drill press for all boring / drilling.

to the people who read this far without reminding me how stupid i am, thank you for all your tips help, advice, criticisms, and so on.
thanks..
 
Hi and welcome to the forum :)

For bearings bronze or gunmetal works best for steel crankshaft, castings can be bought in cast iron, Which machines usually quite well, then there is the softer metals of copper brass and Ali. Any steam fittings should be bronze, you may be better off as a newby building a model from a set of castings from AJ Reeves or PM research. What you need to be watching when you watch YouTube is the setup, not the actual machining, if that makes sense. How the work is held and supported while setup, and how it's dialed in for accuracy.

What lathe have you got by the way as people may be able to advise better knowing what the capabilities of the lathe can handle :)

Ps I'm a newby to machining too, and have followed the same path when it comes to watching YouTube to learn. Though books are also a great resource.
 
Also, as for lack of tailstock, it does make things trickier, i would suggest trying to fabricate and machine a new one before progressing onto making engines, not only will this make everything easier, but it will get you used to some of the operations that you'll use while making steam engines.
 
Hi and welcome to the forum :)

How the work is held and supported while setup, and how it's dialed in for accuracy.

What lathe have you got by the way as people may be able to advise better knowing what the capabilities of the lathe can handle :)
yes I do understand lathe capabilities. I have every limitation in the book and then some because i have the famous harbor freight 7". it would serve better as a anchor for my boat. but I also understand about how the jaws grip softer metal. and I know first hand how sh** can go flying out of the chuck for any number of reasons. I am also making a tail stock w/ live center right now as per tubilcains steam videos on youtube. (well educated man right there)

I am also in the process of making a faceplate / pallet to bolt down irregular shaped objects. and then another pallet to attach to the crossslide with a z axis adjustment so I can use those wonderfull harbor freight mill tooling in the lathe kinda like a horizontal mill.

you have to get creative when your poor and dealing with JUNK! but Im used to it.

thanks for the tips
 
is there a rule of thumb about bore and stroke and steam pressure required?
are there any links to steam engine math?
 
stevecobb76,

I would be helpful if you edited your profile so that your location shows. We can provide better information as to sources for help if we know where in the world you are. You can be as specific as you are comfortable with.

I think you are in the USA.

If you have the 7-in. mini lathe and you don't have a tailstock, then LittleMachineShop will sell you one.

https://littlemachineshop.com

I get nervous reading "newby" and "I want to build a boiler" together. Not that it can't be done, but read the cautions and regulations on this and other forums. You can start building "steam" engines that actually run on compressed air to get started.

When you get started with a project, no matter how small, start a thread and include pictures so we can enjoy your journey. And some of us even like looking at shop pictures and threads about machine-setup.

Welcome and hope to see more.

--ShopShoe
 
stevecobb76,

I would be helpful if you edited your profile so that your location shows. We can provide better information as to sources for help if we know where in the world you are. You can be as specific as you are comfortable with.

I think you are in the USA.

If you have the 7-in. mini lathe and you don't have a tailstock, then LittleMachineShop will sell you one.

https://littlemachineshop.com

I get nervous reading "newby" and "I want to build a boiler" together. Not that it can't be done, but read the cautions and regulations on this and other forums. You can start building "steam" engines that actually run on compressed air to get started.

When you get started with a project, no matter how small, start a thread and include pictures so we can enjoy your journey. And some of us even like looking at shop pictures and threads about machine-setup.

Welcome and hope to see more.

--ShopShoe
i would have to consider myself more qualified than most to build a boiler.. lol. I graduated from tampa bay tech in 1996. I studied welding (metalurgy) for 4 years there. Arc, mig, tig, and torch: soldering, welding, brazing, and cutting,
we built alot of trailers and grills and battering rams for the Hillsborough county police department.
I also do alot of plumbing being a handyman. I understand what makes a good solid joint and I know what happens when I screw a joint up. (I have a few times and i had to go back and fix it)

pictures.. yes there are pics coming. I draw my ideas on paper first. then I do them in 3d on the computer using blender 3d. Then everything gets changed as I do it in the real world! I am never limited in my capabilities of fabrication. I am only limited in money and available suplys. So I do the best I can with what I got most of the time.
 
for me, I draw on paper first. then I draw in in 3d on the computer. then I build. right now, I still have alot of planning to do on paper
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You have lots of questions hopefully i can respond to a few in an understandable way.

When it comes to bearings the ideal situation is to run a hard shaft against a soft bearing material. Running identical materials against each other is never a good idea.

Don't knock the 7 x XX LATHES. While it is true they are more kit than machine, the basic parts are there to produce a very nice compact lathe. It does take some work but it is better than shelling out $10,000 for high end watch makers lathe or bench lathe. These little lathes show up in all sorts of places from reloading benches to CNC retro fits.

For materials in small quantities there are all sorts resources available. Start with the online resources such as McMaster-Carr, MSC, Speedy Metals and a bunch of others. There are usually supplies at model engineering showsa
 
Great tips Wizard69. thanks. now that I know what materials to use for the bearing blocks, I can start really designing it. and the harbor freight lathe 7x 11 boat anchor does work pretty decent now that I got 95% of the slop out of the cross slide. I am currently building a quick change tool holder for it. and I gutted a old 3/4 drill so I can make a tailstock for it.. I am also building crossslide lock for it.

WARNING *** off the wall redneck engineering question ***
last question for a while. I asked this before but I didn't know what I was trying to ask until I thought about it:
instead of buying casting(S), can I solder 4 layers of 1/4" copper plate to make a 1" thick plate or 8 layers to make a 2" thick plate? and then bore my cylinder and piston valve into that?
if so, should I make the bore of the cylinder parallel to the plates? I dont think there would be any cylinder wear problem that way? your thoughts?
my beam engine design thoughts right now are a 2" to 3" bore and a stoke of about 5". total of 2 cylinders, 2 beams, and 2 lead flywheels.

I got the time to do it because of some medical stuff going on thats keeping me from working. And I am trying to save as much money as I can because of my very limited income due to medical.

and yes I solder and weld good enough. (better than most I have seen as a handyman) Im not certified, but I did goto tampa bay tech high school. I studied welding for 4 years. over 2500 hours of Arc, mig, and tig. with the torch, I can solder, weld, braze, and cut. I love building things. and I dont really care how long it takes. thats all I got is time because of my medical stuff going on.

thanks to everyone here for helping me.
 
You could just design the engine to be made from Aluminium, it's easier to work, will weld, screw, together and machines easily, design it so that your bearing surfaces (cylinder liner, crank bearings ie the more expensive materials) are minimal and inserted into the machined Aluminium, make sure to include a step on the outside of the cylinder liner , and the reverse on the cylinder which can locate it and keep everything in line and prevent movement. Same goes for crank bearings.

I sent you a link in a PM for the Elmers engines these are all built from bar stock, if you study the drawings of the models you might like to make, you may find that you only need a few standard sizes of metals to build several of the models.

Some people have good results from scrap yards, but often the materials are in the same region as if bought new from a shop. The choice is yours.

Good to hear that apart from lack of tailstock at the moment the machine seems all ok ;)
 
Great tips Wizard69. thanks. now that I know what materials to use for the bearing blocks, I can start really designing it. and the harbor freight lathe 7x 11 boat anchor does work pretty decent now that I got 95% of the slop out of the cross slide. I am currently building a quick change tool holder for it. and I gutted a old 3/4 drill so I can make a tailstock for it.. I am also building crossslide lock for it.

WARNING *** off the wall redneck engineering question ***
last question for a while. I asked this before but I didn't know what I was trying to ask until I thought about it:
instead of buying casting(S), can I solder 4 layers of 1/4" copper plate to make a 1" thick plate or 8 layers to make a 2" thick plate? and then bore my cylinder and piston valve into that?
if so, should I make the bore of the cylinder parallel to the plates? I dont think there would be any cylinder wear problem that way? your thoughts?
my beam engine design thoughts right now are a 2" to 3" bore and a stoke of about 5". total of 2 cylinders, 2 beams, and 2 lead flywheels.

I got the time to do it because of some medical stuff going on thats keeping me from working. And I am trying to save as much money as I can because of my very limited income due to medical.

and yes I solder and weld good enough. (better than most I have seen as a handyman) Im not certified, but I did goto tampa bay tech high school. I studied welding for 4 years. over 2500 hours of Arc, mig, and tig. with the torch, I can solder, weld, braze, and cut. I love building things. and I dont really care how long it takes. thats all I got is time because of my medical stuff going on.

thanks to everyone here for helping me.


I wouldn't laminate myself. I suppose it depends a bit if this will be a nonfunctional model or a real internal combustion unit. I certainly wouldn't trust soft solders in a functional engine.

As others have pointed out aluminum is a good place to start. Look for a local supplier selling drops, machine shops willing to sell scrap, and other sources of non prime metal. Sadly the local scrap yards will not sell scrap metal but it never hurts to ask at your local junk/scrap dealer.

The other nice thing about aluminum is that it melts nicely allowing you to recycle old car parts and etc. a man named David Gingerly wrote a series of books on the use of scrap aluminum to build machine tools. Those books are full of useful information.
 
It just hit me... i can laminate the crank case using hard silver solder. The key to making it work is sleeving the cylinders!!!!!!!!
 
It just hit me... i can laminate the crank case using hard silver solder. The key to making it work is sleeving the cylinders!!!!!!!!


Id still would be reluctant but a sleeve properly sized would make me feel a bit better. You still will have problems with porting and bolting on end caps.

With your background id seriously consider castings out of aluminum. It should be far easier to accomplish than reliable laminates.
 
Id still would be reluctant but a sleeve properly sized would make me feel a bit better. You still will have problems with porting and bolting on end caps.

With your background id seriously consider castings out of aluminum. It should be far easier to accomplish than reliable laminates.
I have been thinking About this very thing. I bought stuff today to make a propaine forge. I have been breaking up scrap aluminum and i spent most of the day lapping in the ways on my harbor freight boat anchor lathe. Started with 3 rounds of permatex valve lapping compound follow by blue magic and mothers. It is amazing how tight i can adjust it now but how easy it moves at the same time.
I will be building my forge tomorow.
 
I figure before i get seriouse about a steam engine, i need to get my tools up to par. So here is after 4 hours lapping the ways on my lathe. Tomorow, i will be building my aluminum forge. They are 100% better but still need work. Not bad for my first try. I did the ways and both joints on the cross slide.

20180317_224434-1338.jpg
 

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