How did they cut the “Figure 8” lubrication grooves in sleeve bearings in the old days?

[bcall2043]

I thought some of you might find this machine topic interesting. Not a hobby type machine but kind of cool anyway.

Have you ever wondered how they cut the nice “Figure 8” oil or grease grooves in the sleeve bearings such as those used in some of the machines you use in your shop? I know in today’s world of CNC machines it is just a matter of programing but in the old days how was it done? If you do a search you will find the question has come up before many times. The following link is from another forum and one of the many on the subject floating around. A lot of posters had thoughts and memories but not a lot about real live old machine tools designed to machine the internal lubrication grooves.

Here are two interesting vids of channels being cut by a talented young European machinist.

Machining grease chanel in bronze bearing inside by 1K62 lathe - extreme machining - YouTube


Machining greese chanels in bronze bearing inside by 1K62 lathe - how I was did it - YouTube
I had recently read that thread and had been thinking about it but put it out of my mind for a while before going to the Fort Worth, TX area last week for the holidays. While there I visited an old friend who I use to work with many years ago and now owns his own machine shop. He has a lot of old machines of all kinds and gave me a tour. He had found and hauled home an early machine tool that appears designed just to machine those lubrication grooves. The photos below show the machine and a piece of plastic pipe he used to setup and test the machine before cutting a new bearing for a lathe he was repairing. As you can tell from the photo the machine does not get used often but he is keeping it just in case.







The machine is a combination of a lathe and a shaper. The spindle holds and turns the bearing while the carriage holds the cutting tool and moves it back and forth in the bearing bore while it cuts the groove. My friend says he now cheats when he needs to cut a groove. He rigged up a ball-burr in a die grinder to make the job go faster.

I have a video (my first) of the machine going through the motions but don’t know how to attach it since it might be too large. I can try and post it if anyone can tell me how.

Benny
The Orphanage Never Closes

 

[ABB]

Thank you for sharing that..I was just cleaning my SB cone pulley bore the other day and wondered just how that was done...Cool!

 

[OlCatBob]

Benny,

thanks for starting this thread, i would certainly like to see your video. Hopefully the administrator here would work with you to place it on the board. It is amazing that long prior to NC or CNC, someone would be innovative enough to come up with something like that.
See ya,
Bob

 

[OldMachinist]

Here's page from a 1919 book about oil grooving machines.

 

[george wilson]

Oil grooves could be cut with a special lathe attachment that was geared to a sliding compound.

 

[bcall2043]

Benny,

...........i would certainly like to see your video..............
See ya,
Bob

Bob,
I will move it over to the laptop and put it in the truck so next time we run in each I will have it handy. Or I could email it to you. Not sure how large a file you can receive, file is about 64000k. Meanwhile I talked with Charley today and he told me how he posts videos here and I will look into trying his method.

Here's page from a 1919 book about oil grooving machines.

Don,
Thanks for posting the book page. That is the same company that manufactured the machine in the photo. The photo just shows a "newer improved version". I had searched on the machine mfg. name and found nothing. Gary the owner had told me that the machine would cut the various grooves shown in the book but I had forgotten to mention it.

I was thinking today about how sad it is that when people like my friend Gary passes, someone is likely to junk all the older machines he has adopted. He and I were discussing where some of the newer machines he had came from and he mentioned a local (to him) aircraft company. The company no longer manufactures a certain aircraft model for the government and scrapped the related tooling/machines and installed new for the current aircraft models. Most business owners today don't want an old machine around that is only used once in a while and us hobby machinist do not have the room to save a specialized machine like this.

Benny
The Orphanage Never Closes