Van Norman 16 Mill: Leaking seal between spindle and gearbox-

[Bob V]

Hello,
A few years ago I removed the spindle on my Van Norman Mill and sent it to Wells index and had the spindle re-ground to an R8 spindle so I would have a greater variety of tooling-- and to decrease runout. This project worked well, but ever since this was done, the spindle oil has been leaking into the gearbox, so the oil level in the spindle drops, and the level in the gearbox rises --so I have to drain some oil from the gearbox and add oil to the spindle. The machine is usable but this is annoying.
I want to fix this by replacing the shaft seal between the spindle and gearbox.
--Any advice on doing this? --Are seals like this readily available? Where should I look for a shaft seal?
Thanks in advance for the help.
Bob

 

[markba633csi]

You should have no problem finding a seal to fit, you just need the correct size info or part number. Once you remove the old one you can get the relevant info by measuring it. It may even have a part number if you're lucky, but many don't.
-Mark

 

[tq60]

Take the seal to a bearing supply

Sent from my SAMSUNG-SM-G930A using Tapatalk

 

[Rickv100]

You can cross reference the seals on the Timken website.

 

[samstu]

I replaced a seal on knee of my VN16 and used the number off the seal. The only issue I ran into was the seal number was obsolete (Garlock 346). I added a leading zero, searched garlock's catalog and found 3 seals with xxxxx-0346. 21158-0346 was noted as "standard", so this is what I crossed to an SKF which was on Amazon for cheap. I did confirm with measurements which were simple fractions, ie common industrial seals. The newer seal was much thinner than orginal (and not leather). If your seal is inexpensive, you might order 2 and double up. This may also give some advantage on a worn shaft too with a new contact area.

Please take a couple pix and/or post a note telling us how this went and the seal number you used. As a fellow owner, I will be interested. Thanks!

 

[Bob V]

samstu,
Thanks for the information.
I'll post pics on how this is going-- it's already much more interesting than just replacing a seal-- the key locking the bevel gear to the gearbox shaft had been totally sheared off and spun about 90 degrees before becoming cold-welded to the shaft-- so now I have to clean up the gearbox shaft and the inside of the gear as well as the seal replacement. This severe crash may help explain the fact that the table translation system is missing parts for the motorized system.
Bob

 

[Bob V]

Update on my seal replacement— and new problem!
I got the old seal out and found a seal to replace it (National Seal # 240189) for the 1 1/8” shaft.
BUT while removing the gear to get at the seal I discovered that, at some time in the past, the gear shaft key had sheared off, rotated about 1/3 revolution, then cold welded to the shaft— so the mill kept operating. I’ve attached some pics of the mess. I bored the cold weld off the inside of the gear, then put the lathe toolpost on the mill and turned the cold welding off the shaft.
Please look at the pics— there is a full length key way inside the gear, but a very short key way in the shaft. Looks to me like this is why the key failed— does anyone agree? Seems very odd to me that this would be OEM. What do you guys think?
Also, it looks like I now have to take the gear train out of the gearbox And get someone to complete the key way in the shaft.
Has anyone taken apart a VN 16 gearbox? —any advice? Any surprisesto watch for?

 

[Superburban]

I would be very surprised if someone made a new shaft. My guess is they use the short key as a shear pin to prevent damage to the gear train. It also looks like the sheared key was longer then the keyway in the shaft. wondering if someone hammered it in, starting the shearing.

 

[Bob V]

SuperBurbank,
Thanks— and yes— The sheared off key I removed was much longer than the slot in the shaft. Would you radius the new key To get a bit more purchase or just use a very short key?
Thanks for the help.
Bob

 

[Superburban]

I would definitely radius the key. Aren't the partial rounded one hardened?

A hardened one kinda defeats the idea of it being a shear pin. I think I would go with normal key stock, and fit it as much as possible. Then check it after a few months, and then about a year. Look for any signs of shearing.