The Home Machinist!

Thank you for the replies and ideas. I will take a bunch of measurements and make some ref marks on components before I tear into it this weekend. Once I get the gears out of the cutting head I can take some actual part measuremnts to see if something on Boston Gear might be adapted..... I'm still hoping to find that elusive spare that someone had stashed away.

Montie

spro wrote: ↑Wed Jan 15, 2020 1:04 am Might be, from another Van Norman No. 12. These look hypoid to me. It would be great if deep in lower levels of stock gear parts, a set was found.

They do not appear to be hypoid—hypoid gearing is not found much in machine tools. The appearance and helix angle suggest to me they are spiral bevel. Boston Gear, Browning and some others have spiral bevel gears with hardened teeth.

Bill Shields wrote: ↑Wed Jan 15, 2020 7:52 am They look like spiral mitre. Seriously doubt that van Norman actually made their own gears.

look here in the Boston Stock Gear section for SPIRAL MITRE GEARS: 2:1 / 1:3 / 1:1 ratios

https://www.bostongear.com/ecatalog?pag ... HLSK102Y-L

you will find something...just do you want to $$$ the price?

Pedantic note: a miter gear set has a 1:1 ratio. A bevel gear set has a non-integral ratio. The failed gears are likely spiral bevel.

Man. You are way over my head. Spiral Bevel seems right but what he needs is transmission. A newer unit with newer bearings and he told me that the spindle was machined to R8 . So unless a person has a stash of 5V collets, the originals won't work.

I'm not crazy about the R8 mod, but the mod is made... They also made an R8 arbor, and I have a lot of R8 tooling, so not to bad. It works ok, just not going to be able to take as heavy of cuts as I could have with the 5V.

In my notes; says that the Van Norman head is a sub head. They were supposed to fit #6, #12 milling machines. Mine is V5c taper. Measurements are the head is 9 1/4" long with 6 1/8' graduated base 3 mount holes. Some of this should apply.

Bill Shields wrote: ↑Tue Jan 14, 2020 9:17 pm i would be very surprised if you could not find 'stock gears' to replace what you see...

X2 This is the first thing that I would check into.

Hello Gents, Got the cutting head off, but not quite torn all the way down yet. I have had no feedback from anyone with actual VN 12 gears so far, fingers still crossed.....

Okay so all the measurements I conveyed are nothing.

Hello Spro, Sorry, Are you referring to your cutting head measurements? I have not had a chance to take any measurements of my cutting head.

I was getting a little confused there too. There is the main head and then the "sub" head which we start calling the "cutter" head. That head was modified for R 8 collets which go much larger than Van Norman C5 collets. I think (uh oh) the V N collets maxed out at 5/8" ID. I never saw one above 1/2" for the sub head/ cutter head But larger end mills could create stress back to the main head.
The sub head is really stout and difficult to break, within it's capacity but something did break further up. So maybe the R 8 mod wasn't such a good idea after all. You need to investigate the sub head . It may have locked up during heavy use and caused the main head to lose teeth.

Hello Spro, Right, wrong, or uncommon of the terminology the Van Norman literature from that time frame refers to the "cutter head" as the portion of the machine which arbors and collets are mounted for cutting metal; So I was just using their terminology. I have removed other covers from the machine and inspected all the gears which are visible and all are ok, and with the cutter head removed everything rotates smoothly with no binding or excessive slop. Someone may have run the cutter head with no oil at some point in the past, and that is a sure way to destroy helical gears. My fresh lube and rotating the head from horizontal to vertical allowed some trash (old broken gears) to float down into the ring and pinion. My gut feeling was to removed the cutter head and remove the old oil/grease/etc. before I started the machine, but I didn't............ always go with your gut.