Russian machinists.

[plunger]

Yes it is clever and I hope I can remember when I need to cut a hole like that!

Yes,will I remember.

[The Artful Bodger]

This is clever.
https://www.youtube.com/watch?v=iPA645QCLHE

Yes it is clever and I hope I can remember when I need to cut a hole like that!

[plunger]

This is clever.
https://www.youtube.com/watch?v=iPA645QCLHE

[MattiJ]

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.

Predrilled hole makes morse taper more likely to spin. Morse taper needs enough feed pressure to hold.
if you have to predrill keep the drill size quite small.

[nickel-city-fab]

Ya, some of the East European machinery is very well built. It reminds me of the older American machinery, same thing. The "baby" Axelson lathe could take say 60cm x 2 meters but it weighed ~8 tons!

[plunger]

I think he is relying on the steel gear to lap the brass gear to get it too mesh properly. He has quite a few ideas that are almost there like his triangular drill bit. It was quite ingenious how he machined it.
I just love their lathes.
They are butt ugly but you can see they are built like a russian tank.
They just look very rigid for such a small footprint.

[plunger]

Years ago I was hired to run a large radial drill, it was nothing to plunge 2" (50mm) thru 10" (800mm) in one go. All Morse taper shanks with coolant thru.

That brings back memories for me as well. As an apprentice I would need to block up the die plates for 25 liter bucket molds as well as laundry basket molds.. It would involve squaring up plates on a huge milling machine and then take the block via a forklift to a huge surface grinder and then take it to a huge radial arm drill to pre drill huge holes for the columns before it would go to a jig boring machine to get the dimensions spot on.
That was a lifetime ago.

[nickel-city-fab]

Years ago I was hired to run a large radial drill, it was nothing to plunge 2" (50mm) thru 10" (800mm) in one go. All Morse taper shanks with coolant thru.

[eKretz]

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.

First, that is a pretty large lathe. Second, he is using an extremely low feed rate. Third, if the drill is sharpened with correct geometry so that it is free cutting, this is an everyday occurrence in a machine shop. I've drilled up to 6" holes from the solid, and I'm sure others here may have done even bigger than that.

[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.

[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

[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

[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.

[plunger]

Sorry I forgot to attach the youtube video. Have a look at 40 seconds.
https://www.youtube.com/watch?v=OFiJPECzZo8&t=238s

[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