Russian machinists.

[JRouche]

Stainless steel gained the most.

Pretty much why SS gauls so well.JR

[CCWKen]

You won't do that on a flimsy lathe. It's just like trying to make Knurls with a push tool. I followed that guy for a long time. Way back when he was on an old lathe in a dark corner of that factory. After he started making YT money, he started making toys and built or bought a new apartment. I kind of "forgot" to go back and look after that period. Just like another machinist we know. The videos just became play-time.

[macona]

Writing in the 1930s, the late Fred. H. Colvin reported that roller finished cylindrical surfaces had a high grade finish, but the process produced a wavy, out of round finish with micro cracks in the surface when examined under a microscope.
So, what is the difference between roller burnishing as practiced in the 1930s, and roller burnishing 21st century style?

Better steels maybe? Or he just does not know what is happening on the microscopic level.

[dian]

i burnish to size often. i do it with the bearing race. i dont see any advantage in using the ball.

and yes, for 0.15 mm infeed you need a stout lathe.

[MattiJ]

i burnish to size often. i do it with the bearing race. i dont see any advantage in using the ball.

and yes, for 0.15 mm infeed you need a stout lathe.

I have used also bearing race.
Ball might be better in a way that contact area is smaller and it probably needs less force. Also no need to worry about bearing "shoulder" digging grooves to workpiece. (happen to me once before I rounded/polished the shoulder slightly with bit of abrasive paper)

[dian]

hm, i do it with the edge. so not even sure area is smaller.

[MikeWI]

Couldn't you rig something like a scissors knurler is made to reduce the forces on the lathe?

[plunger]

This is another Russian machinist and Im fascinated how he drills at 40 seconds in the video. He doesn't even seem to bother with a pilot hole or center drill. I cannot believe how easy he makes it. I tried this with a 32mm drill in a predrilled hole the other day and my drill started spinning in my tailstock to my horror.

[A.K. Boomer]

He said .01mm (dia. reduction).
In his previous videos the reduction was .01-.055mm (more reduction was in stainless steel)

His goal is to increase surface hardness. In one of the older videos he demonstrated surface hardness increase from about 25% (for harder steel) to about 100-250% for softer steels. Stainless steel gained the most.

This is what I thought the main reason for doing it would be - you can get great surface finishes with just machining the part with a nice sharp radius tool,

but the ball/roller method gives similar results to if the part was shot peened - with of course the lack of rough finish,,, it increases the surface hardening and also the skin density of the part itself, great for increasing durability...

[A.K. Boomer]

I wonder about a down and dirty home brew that could be made with about 1/20th the effort and perhaps potentially even better results,,, instead of two ball bearings and his shield, just take a ball endmill to the business side and sink it about 3/4's deep, if you want to get fancy drill a small hole in the center then a 90 degree connecting hole for gravity oil feed, Stuff a ball into it, walla - it's going to rotate and also allow the higher unit pressure business end of the ball, and even the side forces are better off then what he's got,,, I think it might work just as good maybe even better...

EDIT; I just tried my theory out - could not get the ball to rotate it just dragged --- but my ball end mills are old HSS junk and smaller than the ball so I was side stepping to get the ball to fit in, still no luv, im thinking the piece holding the ball would have to be hardened --- and i was just using mild 1045

don't know - if anyone can make it work lmk thanks

[plunger]

Sorry I forgot to attach the youtube video. Have a look at 40 seconds.

https://www.youtube.com/watch?v=OFiJPECzZo8&t=238s

[MikeWI]

When I was learning how to sharpen drills, I did a 142 degree 4-facet split point on a 1" MT3 drill bit. Drilled thru mild steel with no pilot and no effort! I was amazed.

[Hal]

i burnish to size often. i do it with the bearing race. i dont see any advantage in using the ball.

and yes, for 0.15 mm infeed you need a stout lathe.

any pictures or more info about burnishing ?

Thank you

Hal

[plunger]

Some more interesting stuff. What do you think the orange material is . This is a very interesting alternative to making a gear.

https://www.youtube.com/watch?v=qb9C7qCkbG0

[eKretz]

Some more interesting stuff. What do you think the orange material is . This is a very interesting alternative to making a gear.
https://www.youtube.com/watch?v=qb9C7qCkbG0

Probably some form of clay. The process shows promise in a pinch but he definitely didn't do a great job of hitting the proper gear tooth dimensions. The new gear barely meshes with the larger gear at all. It probably won't last long.