Regrinding the spindle of machines to accept different tooling?

[HMF]

Hey Guys,

I own one mill- it takes 5V tooling (Van Norman 5c)
I own another mill- it takes BS9 tooling.

Tooling up each machine is expensive and often a pain. BS9 arbors for the one mill are rare and expensive. The arbors for the other mill are $100 each when you can get them.

So here is the question: What about regrinding spindles to accept R8? It's readily available.
How hard is it? How expensive is it to have a machine shop do it? Any negatives?

Thanks,


Nelson

 

[HMF]

Shadow:

Another stupid newbie question-

How involved would it be to fabricate a new R8 spindle? I assume the dimensions are available, and it would be a matter of setting up the lathe properly.

Thanks,


Nelson

 

[Tony Wells]

Given a choice, I'd examine the existing taper and see if there was material there to safely modify it.

For casual, hobby use, making a serviceable spindle would be a good exercise. I'd use 4340 commercial HT, and rough everything out, leaving stock on the critical surfaces. Of you could fit it in the kitchen oven, a little time would help stabilize it. If not, just 24 hours on the floor will help a little. The hardest part for the home machinist will be the through hole. Not really critical for size, but it is a deep hole. If the spindle is for high speed use, concentricity of the hole becomes more important.

 

[Tony Wells]

Hehe, that's what you do when somebody has a lil wreck.

 

[mosedawg56]

It seems to me that if you are contemplating the machining of your spindles, you also have the capability to machine your own arbors as well. I would consider that before I ran the risk of destroying my antique machinery. The dimensions of the tapers are readily available. I machined a 5C stub arbor to attach a 4 inch four jaw chuck to for use in my Heavy 10 and it works mighty fine. I found the dimension chart on one of the Southbend forums, but I can't remember which one.