Great attempt. It’s not a failure. You succeeded in determining that twenty small balls isn’t better than three large ones. And you got to make a great looking tool as well.
You probably need a smaller diameter race for the parts your trying to burnish. I haven't seen rotary burnisher used since 1970's but it was used to burnish bearing bores (also finished them to 0.003mm tolerance, 35mm and 42mm bearings) The pressure was quite high considering it was being used on cast iron, setting tool broke a few castings when tool setter went too far. It also got used on stainless steel when parts were being made to take to a 'Trade Show' in London (UK) I made the parts then got laid off ( along with another 29 people 😕- last in, first out)
I don't think the race is allowing the bearings to feed with the part. to feed across the surface I think the bearing would almost have to be in a caster. otherwise as you feed across the work, the ball will try to climb up one side of the race making it lower at that point. it would take much more work, but a set of bearings in individual casters fixed to one head may do better, in theory. this would also give you an opportunity to put and extremely high spring rate on each caster so that each will self adjust as well as adjusting the unit with a heavy spring. another option would be to use a hydrodynamic bearing of sorts so that the ball bearing doesn't connect to race allowing for aliment with the axis motion and rotation.
Everything you say makes sense and can explain my failure with this tool, but unfortunately I don't have the motivation to made another improved model at the moment. It will take at least two days for my enthusiasm to return :)) Thank you for your comment and your suggestion !
Great build, sorry not results you where looking for but, maybe think of it as if you where doing this on lathe. Would they not be a lot more pressure pushing against the part you want shiny?🤔 maybe more downward force with quill?🤔 not exactly sure, but that's our 2 cents and hope it helps 😉👍
It is a true that a bigger press could be a solution but unfortunately my milling machine is not very robust and because of this its pressing is limited. I regret enormously that I cannot try this idea :(( Thank you very much for your comment !
Nice try but I doubt the surface will be flat or even as the balls will try to ride over the edge and bump along........a surface grinder is the method we use, and it is a tried and trusted solution to a flat and fine surface.
I think there are a couple things you could do to improve results. One is fortunately easy to test. I think every time a ball goes off the side of your part it will relax downward a bit, and then when suddenly slammed back into the workpiece, it will have to jump back up, creating a bit of chatter. Does the finish improve when going down the middle of a workpiece wider than the circle of balls, such that there isn't an interrupted "cut"? The other thing that might help is applicable to then other design, but impossible on this one. You may be able to interrupt the formation of the waves before they get to such a height as to overwhelm the balls by having two sets of three balls, such that one is further out from the axis of rotation of the tool by one ball radius. That would make each ball flatten the peak of the wave created by the previous ball.
The contact surface of the ball with mirror is extremely small. Hm. A very interesting idea. Let each ball have its radius and its path so that it does not follow the same tracks? Did I understand correctly?
You’re on the right path. Polishing steel via burnishing is a metal displacement process that tends to work on metals that are 45HRC and below. Perhaps you are trying to polish a steel that is greater than 45 HRC not allowing the bearing balls to displace the metal as smoothly as possible. Try testing out your burnishing tool on a variety of metals to see what the range of results can be achieved with the tools at varying spring pressure, feeds and speeds. Great looking tool!🤠
Unfortunately, I don't have data on all the types of steel I have. I can only approximate their hardness ”by eye” and I can tell you that the metal plate used is not very hard. I have not tried on aluminum or copper or high alloy steel. But it's an good idea. Thank you very much for your comment !
Unfortunately, you won't even find it on planet earth :)) I adapted this chuck to fit my lathe and if you want, watch my video ”No mistake allowed” and maybe it will help you to modify one as I did. Thank you for your comment !
Hi, I think you are doing well in trying to make improvements - so I applaud your motivation & dedication to it!! Have you considered conical rollers? this way you have a larger, linear surface contact area so it will help flatten the surface instead of pushing a groove with the small point contact of the balls... I hope you keep experimenting. Stay safe and well - Anthony (from Australia)
Hi Anthony. Yes, I thought about conical rollers but unfortunately my pressing force is reduced. I can't press harder and for your idea to be effective I assume that a more robust machine is needed. Thank you for your message of encouragement and the kind words you sent me. It means a lot to me. Stay safe and well too, my friend !
Hi Jimmy, I hope you are well. One thing I see right off @ 5:33 is your indicator is at a steep angle to your work piece. That will give you “cosine error” since you are measuring on an angle more than 90 degrees.
Hi Arnold ! I hope you are well too, thank you. I will have to buy a dial indicator with longer action. I couldn't seat properly because I was very close to the chuck jaws. Thank you for your comments !
While he would be getting a cosine error, wouldn't that only matter if he was measuring different heights instead of just centering his part? From what I'm seeing there is nothing wrong in using it at such an angle for this purpose.
One of the reasons you are having trouble getting a good finish with the fly cutter is because you are using a carbide insert tool. Try a piece of high speed steel stoned to a super fine finish ( I use a 150 grit wheel and finish with diamond or stone) a real light depth of cut, .002” or so, fine feed and oil. I did have one machine that would not give a nice finish with a flycutter at all, ever. If you are having problems with loose particles try using an orbital sander with 180-320 grit paper before the burnishing tool and wipe it down in between
Do you think the diameter of the burnishing tool vs. the width of the plate along with the small chips left after fly cutting the surface may affect the results? My thought is maybe the ball jumping up and then back off the surface causes an adverse reaction? I think you idea is great, just keep trying to improve your design. Thanks for sharing.
I had this idea of trying to process a sanded surface with a belt sander in order to have a more friendly surface with this tool, but I gave up because if I prepare the surface so thoroughly, this burnishing tool is no longer useful. It is very likely that you are right. Thank you very much for your comment !
Theory : the Z force on the spindle is coupled to the work is 100% for (one) burnishing ball but it takes longer to cover a given work area. We have to apply X amount of Z force for X times more balls. To achieve same smoothness but X times faster. The spring idea goes adversely that. A polish compound and a buffer mat can do just that, faster and shinier.
My goal is to use this process and try to improve a tool already exists and through my ideas to make it usable by all of us. So far it seems that I have not succeded. I am not a standstill to polish a piece and make it shiny but I don't know the method to do it :)) Thank you dear friend for your comments ! It is always a pleasure to read your comments. As for your theory, it may or may not be true. It's a bit beyond me.
I think this tool works fine, the unsatisfactory result was due to a poor job with the fly cutter. Increase the radius on the cutter, increase spindle rpm, and reduce feed rate.
Increasing the radius of the fly cutter will cause my entire machine to be off-centered with negative results. I tried all the settings you mention and those hills are visible regardless of feed rate or spindle rpm. The surface is mirror as it should be but those metal waves cannot be removed or I don't know how to do it. Thank you for watching and for your comment !
@@JIMMY916 I wasn't clear, I meant increase the radius on the grind of your cutter, the radius of where the tool steel is contacting the work. After grinding my bits, I drag them on a sharpening stone to create the radius.
@@JIMMY916 I just dug out my smallest fly cutter which has a very unusual grind but always leaves a beautiful surface finish. If you have an email, Ill gladly send you some pics of the grind angles so you can try yourself. This bit cuts on the heel...
I suspect with a light machine like yours less is more, IE you can’t put enough pressure on 20 balls to achieve the desired effect. Kind of like a stuntman sitting on a bed of nails.
Great and logic example (bed of nails) :)) My light machine may be a problem. Except that a stronger pressure would bury the balls deeper in the material and instead of small waves it will produce a ”tsunami”. I can't do this test unfortunately :((
So Are you feeding with a rack or leadscrew? We repair a lot of ammonia compressors that use mechanical packing and the finish has to be flawless. My lathe makes a repeating ridge every .010” or so near as I can tell is because the feed drive gear has an imperfect tooth. The Ganesch CNC lathe uses a ballscrew drive and doesn’t have a problem finishing. My lathe won’t cut a super fine thread otherwise I would use the leadscrew for finishing. One other issue could be stick slip causing erratic carriage movement like when you are trying to get a nice finish on low carbon steel with too light of a cut.
Great attempt. It’s not a failure. You succeeded in determining that twenty small balls isn’t better than three large ones. And you got to make a great looking tool as well.
Yes, it is true that at least I have this consolation :)) Thanks for the encouragement !
Nice experiment. We shared this video on our homemade tool forum last week 😎
Thank you !
Always good to do some experimenting. Just don't stop and go for it.
Thank you sir for the nice words and encouragement !
You probably need a smaller diameter race for the parts your trying to burnish.
I haven't seen rotary burnisher used since 1970's but it was used to burnish bearing bores (also finished them to 0.003mm tolerance, 35mm and 42mm bearings)
The pressure was quite high considering it was being used on cast iron, setting tool broke a few castings when tool setter went too far.
It also got used on stainless steel when parts were being made to take to a 'Trade Show' in London (UK)
I made the parts then got laid off ( along with another 29 people 😕- last in, first out)
I am honored that people like you visit my channel. Thank you for your comment sir !
I don't think the race is allowing the bearings to feed with the part. to feed across the surface I think the bearing would almost have to be in a caster. otherwise as you feed across the work, the ball will try to climb up one side of the race making it lower at that point. it would take much more work, but a set of bearings in individual casters fixed to one head may do better, in theory.
this would also give you an opportunity to put and extremely high spring rate on each caster so that each will self adjust as well as adjusting the unit with a heavy spring.
another option would be to use a hydrodynamic bearing of sorts so that the ball bearing doesn't connect to race allowing for aliment with the axis motion and rotation.
Everything you say makes sense and can explain my failure with this tool, but unfortunately I don't have the motivation to made another improved model at the moment. It will take at least two days for my enthusiasm to return :)) Thank you for your comment and your suggestion !
Great build, sorry not results you where looking for but, maybe think of it as if you where doing this on lathe. Would they not be a lot more pressure pushing against the part you want shiny?🤔 maybe more downward force with quill?🤔 not exactly sure, but that's our 2 cents and hope it helps 😉👍
It is a true that a bigger press could be a solution but unfortunately my milling machine is not very robust and because of this its pressing is limited. I regret enormously that I cannot try this idea :(( Thank you very much for your comment !
Have you considered belleville washers instead of spring?
No, I didn't think of using that type of washers. It's a good idea. Thank you for watching and for your comment !
Nice try but I doubt the surface will be flat or even as the balls will try to ride over the edge and bump along........a surface grinder is the method we use, and it is a tried and trusted solution to a flat and fine surface.
I tried all the methods and almost the same result with this burnishing tool. Thank you for your comment !
I think there are a couple things you could do to improve results. One is fortunately easy to test. I think every time a ball goes off the side of your part it will relax downward a bit, and then when suddenly slammed back into the workpiece, it will have to jump back up, creating a bit of chatter. Does the finish improve when going down the middle of a workpiece wider than the circle of balls, such that there isn't an interrupted "cut"?
The other thing that might help is applicable to then other design, but impossible on this one. You may be able to interrupt the formation of the waves before they get to such a height as to overwhelm the balls by having two sets of three balls, such that one is further out from the axis of rotation of the tool by one ball radius. That would make each ball flatten the peak of the wave created by the previous ball.
The contact surface of the ball with mirror is extremely small. Hm. A very interesting idea. Let each ball have its radius and its path so that it does not follow the same tracks? Did I understand correctly?
You’re on the right path. Polishing steel via burnishing is a metal displacement process that tends to work on metals that are 45HRC and below. Perhaps you are trying to polish a steel that is greater than 45 HRC not allowing the bearing balls to displace the metal as smoothly as possible. Try testing out your burnishing tool on a variety of metals to see what the range of results can be achieved with the tools at varying spring pressure, feeds and speeds. Great looking tool!🤠
Unfortunately, I don't have data on all the types of steel I have. I can only approximate their hardness ”by eye” and I can tell you that the metal plate used is not very hard. I have not tried on aluminum or copper or high alloy steel. But it's an good idea. Thank you very much for your comment !
You could probably switch out the regular bearings for carbide or zirconium bearings for hard steels.
Lucky you with the 4 jaw chuck which matches the machine. I'm unable to find one in the U.S.
Unfortunately, you won't even find it on planet earth :)) I adapted this chuck to fit my lathe and if you want, watch my video ”No mistake allowed” and maybe it will help you to modify one as I did. Thank you for your comment !
Hi, I think you are doing well in trying to make improvements - so I applaud your motivation & dedication to it!!
Have you considered conical rollers? this way you have a larger, linear surface contact area so it will help flatten the surface instead of pushing a groove with the small point contact of the balls...
I hope you keep experimenting. Stay safe and well - Anthony (from Australia)
Hi Anthony. Yes, I thought about conical rollers but unfortunately my pressing force is reduced. I can't press harder and for your idea to be effective I assume that a more robust machine is needed. Thank you for your message of encouragement and the kind words you sent me. It means a lot to me. Stay safe and well too, my friend !
Separately to the question of if it works better, this design seems to be much easier to produce, especially if you remove the spring.
@@theorbtwo Unfortunately the spring has no role. Yes, it's much easier to build. Thank you for your comment !
Hi Jimmy, I hope you are well.
One thing I see right off @ 5:33 is your indicator is at a steep angle to your work piece.
That will give you “cosine error” since you are measuring on an angle more than 90 degrees.
Hi Arnold ! I hope you are well too, thank you. I will have to buy a dial indicator with longer action. I couldn't seat properly because I was very close to the chuck jaws. Thank you for your comments !
While he would be getting a cosine error, wouldn't that only matter if he was measuring different heights instead of just centering his part? From what I'm seeing there is nothing wrong in using it at such an angle for this purpose.
One of the reasons you are having trouble getting a good finish with the fly cutter is because you are using a carbide insert tool.
Try a piece of high speed steel stoned to a super fine finish ( I use a 150 grit wheel and finish with diamond or stone) a real light depth of cut, .002” or so, fine feed and oil.
I did have one machine that would not give a nice finish with a flycutter at all, ever.
If you are having problems with loose particles try using an orbital sander with 180-320 grit paper before the burnishing tool and wipe it down in between
Yes, could be an explanation. Thank you for your comment !
Do you think the diameter of the burnishing tool vs. the width of the plate along with the small chips left after fly cutting the surface may affect the results? My thought is maybe the ball jumping up and then back off the surface causes an adverse reaction? I think you idea is great, just keep trying to improve your design.
Thanks for sharing.
I had this idea of trying to process a sanded surface with a belt sander in order to have a more friendly surface with this tool, but I gave up because if I prepare the surface so thoroughly, this burnishing tool is no longer useful. It is very likely that you are right. Thank you very much for your comment !
Theory : the Z force on the spindle is coupled to the work is 100% for (one) burnishing ball but it takes longer to cover a given work area. We have to apply X amount of Z force for X times more balls. To achieve same smoothness but X times faster. The spring idea goes adversely that.
A polish compound and a buffer mat can do just that, faster and shinier.
My goal is to use this process and try to improve a tool already exists and through my ideas to make it usable by all of us. So far it seems that I have not succeded. I am not a standstill to polish a piece and make it shiny but I don't know the method to do it :)) Thank you dear friend for your comments ! It is always a pleasure to read your comments. As for your theory, it may or may not be true. It's a bit beyond me.
Perhaps it would work on aluminium.
I haven't tried yet. I will definitely do it and we will see the result in a future video. Thank you for your comment !
I think this tool works fine, the unsatisfactory result was due to a poor job with the fly cutter. Increase the radius on the cutter, increase spindle rpm, and reduce feed rate.
Increasing the radius of the fly cutter will cause my entire machine to be off-centered with negative results. I tried all the settings you mention and those hills are visible regardless of feed rate or spindle rpm. The surface is mirror as it should be but those metal waves cannot be removed or I don't know how to do it. Thank you for watching and for your comment !
@@JIMMY916 I wasn't clear, I meant increase the radius on the grind of your cutter, the radius of where the tool steel is contacting the work. After grinding my bits, I drag them on a sharpening stone to create the radius.
@@JIMMY916 I just dug out my smallest fly cutter which has a very unusual grind but always leaves a beautiful surface finish. If you have an email, Ill gladly send you some pics of the grind angles so you can try yourself. This bit cuts on the heel...
I will be happy to see your model. Mine is a bit limited. Please send me pics on nicolae1979nicolae@gmail.com Thank you very much my friend !
Aha. I understand now. I am a slower...Thank you !
I suspect with a light machine like yours less is more, IE you can’t put enough pressure on 20 balls to achieve the desired effect.
Kind of like a stuntman sitting on a bed of nails.
Great and logic example (bed of nails) :)) My light machine may be a problem. Except that a stronger pressure would bury the balls deeper in the material and instead of small waves it will produce a ”tsunami”. I can't do this test unfortunately :((
It is looking like you will end up replicating the original with 2 balls.
So Are you feeding with a rack or leadscrew?
We repair a lot of ammonia compressors that use mechanical packing and the finish has to be flawless.
My lathe makes a repeating ridge every .010” or so near as I can tell is because the feed drive gear has an imperfect tooth.
The Ganesch CNC lathe uses a ballscrew drive and doesn’t have a problem finishing.
My lathe won’t cut a super fine thread otherwise I would use the leadscrew for finishing.
One other issue could be stick slip causing erratic carriage movement like when you are trying to get a nice finish on low carbon steel with too light of a cut.
Maybe :))
@@pvtimberfaller My machine is a hobby one. It's very limited tool. Unfortunately.
ceramic balls?
Steel balls.