This worked exactly as you described. I used the snout off of an old Ford cast iron harmonic balancer. Bored the snout to remove the key slot, and turned the outside to 1.495", which is the bore of the little engine I'm building from scratch. They sealed well with a little oil. Thanks for the video!
I don't think so. All I did was sand the edges using emery cloth to not make them sharp. I didn't want to minimize the surface area in contact with the cylinder wall. Don't know if there is any facts behind that, I just felt like it wasn't a good move to add any kind of edge finish besides light sanding..
Jack A. Because the only place the ring should touch the piston is the top and bottom faces. It’s impossible to get perfect precision and you’d much rather have a small clearance than have “negative clearance” where the piston is pushing the ring out. The ring must be pressed against the cylinder by its own spring force. If it was pressed by the cylinder, then it would bind up. This is one way that seizing can happen, so this clearance also avoids seizing
Mate, did you consider oiling the cylinder bore before doing a trial fit of the piston and rings? If you do that, perhaps there is a lesser chance of marking up the bore with the ring gap edges? It might also be easier to get a better feel for how well the piston and ring assembly fits the bore. I know we used to do this back when I was a (very) young man, working on motor car engines, That was a long time ago, though. I do admire your work, and have often wondered about making home-made rings. On the subject of making the ring gap, would it be acceptable to use a friction cutting disc in a Dremel tool or air grinder, and just cutting through the ring? I'm curious as to why you break the ring rather than cutting it.
Yeah I put oil in the cylinder, but it kept hanging up because there wasn't anything guiding the piston rod and it would get cocked to one side ever so slightly since the piston is so thin in thickness. Car engine pistons have a whole skirt which helps guide it and you don't get the "cocking to one side" effect. I have since finished the bottom cylinder head and now that the piston rod has a guide through the head to keep it straight, the piston fits very well and moves very freely. About the piston rings, yes I could have cut it with a dremel or something, but I wanted to start from a place of the smallest gap possible and then file it down if I need more. Being that the rings were a few thou under what i wanted, I wanted to give myself the best chance. (Hard to explain, hope this makes sense) Thanks for watching and for the comment!
On final fit you showed it was "two hands tight" and you thought you might make a tighter new set of rings later. Did you bother, and what about expansion of the components when at operating temperature? If it is all cast iron, then it all gets bigger at the same rate I assume, so the cold fit is the same as the hot fit. I am just cleaning out a 2" bore then making new piston and rings to suit.....should I aim for 3 thou clearance on a 2" piston? Thanks for this informative vid.......Subscribed
Thanks for the sub! I still have these rings in it. I have not finished the engine yet so I haven't run it under steam, but it seals very well with compressed air so I think I will keep them for now. As for expansion, they will not expand at the same rate. This is because the amount of expansion is linearly proportional to the mass of the substance. Δx = m CΔT, where Δx is the expansion length between two states, m is the mass, C is the thermal coefficient for the material and ΔT is the change in temperature between two states. To really do the calculations correctly, you would need to do some kind of transient analysis, meaning recursively determine how much each part of the engine expands while temperature goes up. The rings will heat up much faster as there is less mass, and will expand at a much higher rate than the cylinder bore. I did some rough calculations but I am still not sure if my rings will be correctly sized. In retrospect, I feel good about them being a bit loose as a binding piston ring due to thermal expansion is a pretty catastrophic failure!
That is the best answer I have ever seen on UA-cam! So the upshot is that it makes sense that the ring does not have a butt joint style gap as it will be ahead of everything else until full temp is reached, and that butt joint needs to be almost closed at full temp. There are rings made in the U.K. That are called "clupet" rings. That is the manufacturers name I think. The ring joint overlaps so the ring will never bind as the clearance cannot close. I will look them up.. They are spec'd on a marine engine by K.N. Harris.
Here is a Cluppet ring. (Tiny image) steamautomobile.com:8443/ForuM/file.php/1/261/clupetring.jpg While Clupet rings are sized, they can fit a small range, say nominal size minus 0.1", but don't quote me on that! Prices from a re-seller are about £25 for a 2" ring, but I am going to contact the company for details as my bore might have to be 2.125 or a bit bigger to rescue the bore surface.
That's how I did the rings on my steam engine. Machined them .010" over the bore of the cylinder and slitted them to size. So far so good with a lot of miles being logged on the engine.
Thanks! Its cast iron because of two reasons. 1. The fact that cast iron has a lot of graphite (carbon) in it which acts as a dry lube. This high carbon content is enough to (for example) not need oil when machining or drilling cast. So it works well for this purpose. 2. The brittleness/lack of ductility allows it to be springy, such that the opening spring motion seals up against the piston walls.
I have a home maid hiy and miss motor with a 6.175 bore Steel cylinder. Stainless rings gualded along with steel rings. I turned some rings out of cast iron from break roters, worked great!
The steam is mixed with oil which suitably coats the inside, preventing rust. It is also a good idea to run it with compressed air and oil for a bit after steaming.
It means I can use usual cast iron sleave and piston rings but it would be better if you refer me some kind of rust proof material for piston rings and sleave.
No, cast iron is the way to go. The oil does a good job at stopping the rust, especially if you use oil and compressed air afterwards. Cast iron's physical characteristics allow it to be springy against the bore with the combination of having self lubrication from the graphite in it. (The only other kind of rings people tend to use for steam engines are silicone o-rings, but these are generally not so good for super heated steam from what I hear.)
Good video.
File a small notch on the inside of the ring where you break it.
This works well.
Just the information I needed, excellent video thank you, regards Doc Cox.
Really nice keep up the good work your an inspiration to all.
This worked exactly as you described. I used the snout off of an old Ford cast iron harmonic balancer. Bored the snout to remove the key slot, and turned the outside to 1.495", which is the bore of the little engine I'm building from scratch. They sealed well with a little oil. Thanks for the video!
That's awesome! Glad the video was helpful. Thanks for the comment. :D
Very good informative video. I've always wondered how rings were made. Thanks for posting these videos.
Thanks for watching!
Excellent work!
Thanks for that, I need to make rings for an old cast iron compressor pump and wasn't sure about clearances. Thanks again.
Awesome! Glad the video was useful!
great, very informative video sir.
Cool project !
Beautiful job
AWESOME!
Perfeito! Bem pensado.
Great
Can't wait.
Hi Remember to save the chips for your Rosebed, they love cast iron chips, Thumbs up.
ya great video supprised you passed on the nodular iron crankshaft piece just found this video if the rest are like this I'm a suscriber
Thanks to u work
Great stuff. Did you cast the main piston cylinder for this engine? Fine job.
respect.
Cool.
Ok thank you ❤️
do you need an chamfers or other corner/edge finishes as found in some petrol engine rings?
I don't think so. All I did was sand the edges using emery cloth to not make them sharp. I didn't want to minimize the surface area in contact with the cylinder wall. Don't know if there is any facts behind that, I just felt like it wasn't a good move to add any kind of edge finish besides light sanding..
ring expander.......also, really should check ring gap in cylinder bore. super cool video though
I made some rings for a moped piston out of cast iron water pipe. The measurements just happened to work out.
thank you for the video. why would you need a .010 clearance behind the ring?
Jack A. Because the only place the ring should touch the piston is the top and bottom faces. It’s impossible to get perfect precision and you’d much rather have a small clearance than have “negative clearance” where the piston is pushing the ring out. The ring must be pressed against the cylinder by its own spring force. If it was pressed by the cylinder, then it would bind up. This is one way that seizing can happen, so this clearance also avoids seizing
Mate, did you consider oiling the cylinder bore before doing a trial fit of the piston and rings? If you do that, perhaps there is a lesser chance of marking up the bore with the ring gap edges?
It might also be easier to get a better feel for how well the piston and ring assembly fits the bore. I know we used to do this back when I was a (very) young man, working on motor car engines, That was a long time ago, though.
I do admire your work, and have often wondered about making home-made rings. On the subject of making the ring gap, would it be acceptable to use a friction cutting disc in a Dremel tool or air grinder, and just cutting through the ring? I'm curious as to why you break the ring rather than cutting it.
Yeah I put oil in the cylinder, but it kept hanging up because there wasn't anything guiding the piston rod and it would get cocked to one side ever so slightly since the piston is so thin in thickness. Car engine pistons have a whole skirt which helps guide it and you don't get the "cocking to one side" effect. I have since finished the bottom cylinder head and now that the piston rod has a guide through the head to keep it straight, the piston fits very well and moves very freely.
About the piston rings, yes I could have cut it with a dremel or something, but I wanted to start from a place of the smallest gap possible and then file it down if I need more. Being that the rings were a few thou under what i wanted, I wanted to give myself the best chance. (Hard to explain, hope this makes sense)
Thanks for watching and for the comment!
That makes lots of sense. Thanks for the prompt reply.
Live centre would have saved chatter and having to move it bk and re clock etc nice vid though 👍🏿
On final fit you showed it was "two hands tight" and you thought you might make a tighter new set of rings later. Did you bother, and what about expansion of the components when at operating temperature? If it is all cast iron, then it all gets bigger at the same rate I assume, so the cold fit is the same as the hot fit. I am just cleaning out a 2" bore then making new piston and rings to suit.....should I aim for 3 thou clearance on a 2" piston?
Thanks for this informative vid.......Subscribed
Thanks for the sub!
I still have these rings in it. I have not finished the engine yet so I haven't run it under steam, but it seals very well with compressed air so I think I will keep them for now.
As for expansion, they will not expand at the same rate. This is because the amount of expansion is linearly proportional to the mass of the substance. Δx = m CΔT, where Δx is the expansion length between two states, m is the mass, C is the thermal coefficient for the material and ΔT is the change in temperature between two states.
To really do the calculations correctly, you would need to do some kind of transient analysis, meaning recursively determine how much each part of the engine expands while temperature goes up. The rings will heat up much faster as there is less mass, and will expand at a much higher rate than the cylinder bore. I did some rough calculations but I am still not sure if my rings will be correctly sized. In retrospect, I feel good about them being a bit loose as a binding piston ring due to thermal expansion is a pretty catastrophic failure!
That is the best answer I have ever seen on UA-cam!
So the upshot is that it makes sense that the ring does not have a butt joint style gap as it will be ahead of everything else until full temp is reached, and that butt joint needs to be almost closed at full temp.
There are rings made in the U.K. That are called "clupet" rings. That is the manufacturers name I think. The ring joint overlaps so the ring will never bind as the clearance cannot close. I will look them up.. They are spec'd on a marine engine by K.N. Harris.
Interesting! I will have to look those up and read about them. Making sure the ring gap is the correct size for the designed temperature is critical.
Here is a Cluppet ring. (Tiny image)
steamautomobile.com:8443/ForuM/file.php/1/261/clupetring.jpg
While Clupet rings are sized, they can fit a small range, say nominal size minus 0.1", but don't quote me on that!
Prices from a re-seller are about £25 for a 2" ring, but I am going to contact the company for details as my bore might have to be 2.125 or a bit bigger to rescue the bore surface.
I've just contacted Cuplet about the ring I need. 2 1/8" is £16 from stock. I have asked about non stock prices.
You could make your rings oversize to provide spring tension and saw them for the split
Yeah I think that is what I will do if these ones don't work out. They seem ok though.
That's how I did the rings on my steam engine. Machined them .010" over the bore of the cylinder and slitted them to size. So far so good with a lot of miles being logged on the engine.
@@littleevan99 doesn't the contacts at the perimeter of ring and cylinder changes,, the curvature
CHANAKYA SINHA like I said. I’ve logged a few hundred miles on it with no noticeable blow by. It worked for me.
It’s harder to get a nice gap this way, I think that’s why it’s typically not done
This is Cool!!! I never seen a piston ring made. Why are piston rings made of cast iron? Great Video nice tutorial Thanks William Orange county, ca.
Thanks! Its cast iron because of two reasons. 1. The fact that cast iron has a lot of graphite (carbon) in it which acts as a dry lube. This high carbon content is enough to (for example) not need oil when machining or drilling cast. So it works well for this purpose. 2. The brittleness/lack of ductility allows it to be springy, such that the opening spring motion seals up against the piston walls.
find a couple of old weedeater type engines ,,use the rings,, make the piston fit the rings
Nice but didn't see you file a ring gap ?
Keep upthe good work
That is because the gap was made at the heat treating stage.
i'm surprised you didn't fit the ring in the bore first to check gap then fit on piston
My factory is for making circlip
Great video!!! I have some scrap stainless tubes. Do you think it will be ok if I use it to make some rings for my chainsaw?
I have a home maid hiy and miss motor with a 6.175 bore Steel cylinder. Stainless rings gualded along with steel rings. I turned some rings out of cast iron from break roters, worked great!
How to over come problem of rust in steam engine
The steam is mixed with oil which suitably coats the inside, preventing rust. It is also a good idea to run it with compressed air and oil for a bit after steaming.
It means I can use usual cast iron sleave and piston rings but it would be better if you refer me some kind of rust proof material for piston rings and sleave.
No, cast iron is the way to go. The oil does a good job at stopping the rust, especially if you use oil and compressed air afterwards. Cast iron's physical characteristics allow it to be springy against the bore with the combination of having self lubrication from the graphite in it. (The only other kind of rings people tend to use for steam engines are silicone o-rings, but these are generally not so good for super heated steam from what I hear.)
I see big accidents in ur future on that lathe.
Lmfao
I watched your video just to see if you know how to make piston rings. You don;t.
Ok well do you have a video that show's how to do it correctly?
Dear God you're no machinist!!!!
Ray who cares?