sacrificial mill vise?

Firstgear

Firstgear

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I have not machined before except for what I could do with my crummy drill press on my work bench....recently, I bought a new PM-950 mill and Kurt 6" vise. I saw a general topic posting that someone bought a cheap $100 vise to be the sacrifice for drilling and making sure that their new Kurt didnt end up with nicks from using to hold items that were drilled.

I thought it made sense and wondered what others thought....comments?
 
Holes in vises are from operator error. My Bridgeport vise is probably 50 years old and has a few minor marks on it. None of them are done by me. Double check every setup, and know for sure how deep you can cut and keep track of it. If you get in a hurry, you WILL make mistakes. I also do a fair amount of work on the table itself instead of in a vise. That is when paying attention really counts...
 
I had not put an endmill to metal before I started with my PM-932, but I watched lots of youtube, read, and did what Bob suggested above. I took it easy at first, until I got a feel for things. I have not drilled any holes in my vise or table, or my rotary table. That is going on 4 years now. If you are careful and think things through you should be fine.
 
While I certainly respect the opinions of the two posters before me, and I agree with parts of it, I think my opinion conflicts with theirs.

You don't teach a kid to drive with a Ferrari. They will make mistakes that are inevitable, and it doesn't make sense to screw up expensive equipment if you don't have to.

I have been machine for 4ish years now, and as recently as 3 months ago I have cut into the jaws of my vise. My machine is CNCd and I jogged the Z down instead of jogging the X axis. I don't think I was being careless, I just made a simple mistake. When I first started, I made many more mistakes much more frequently. My equipment was cheap and my mistakes were inexpensive. That is inevitable, and that is how you learn.

Depending on how much the Kurt vise cost and how much disposable income you have, I might consider picking up a cheap one to learn with. I have seen some of those vises going for $1000+. I just picked up some decent 4" vises for $85. If I had a nice Kurt vice 4 years ago, I would park it on a shelf and use one of the cheap ones for a little while until I got the hang of things.

Just my 2 cents.
 
I agree with Bob et al. One of the most important things to learn as a machinist is the discipline of ALWAYS double checking your set up and clearances. Machining is complicated and rife for mistakes, allowing for sloppiness while learning is not going to instill good work practice. Simple mistakes are simply not being careful enough.
 
I would agree with the others that holes in your vise is the fault of the operator. We all make mistakes and stuff happens but all my machine vises except my Kurt are about 30 years old and none of them have holes or cut marks on them. Our cutting tools go where we make them go. Just don't make them go into your vise.
 
I've hit the drill press vise once or twice, but I'm a bit more careful with the mill like others have mentioned.

The bridgeport I bought came with a vise that's all beat up, looks like it was used for target practice. Replacement jaws and parallels under the work make it usable enough, though I admit that more often than not I just clamp a toolmaker's vise in the thing and indicate off that.

I could see the argument of keeping the Kurt vise in reserve for precision work and getting a beater to work on while learning. It wouldn't take too long to pick a used milling vise up on Craigslist, and if you're in OH it might run you $75-100.
 
Something many of us may not know is that end mills in R8 collets sometimes work their way down and out of the collet when cutting due to the helix of the flutes when doing heavy work and/or if the collet does not grip the end mill tightly enough. After ruining the work, they then ruin the vise and/or the table, and also destroy the cutter and collet, not to mention ruining your day. When in doubt, use an end mill holder, with the end mill pulled down against the set screw before final tightening. It will not pull out. The end mill will need a recessed flat (Weldon flat) in its side for it to work. The Weldon flat also keeps the end mill or other tool shank from slipping in rotation, which damages collets and tooling. I have a full set of end mill holders up to 1 1/4", and rarely use them, but I certainly do if there is any worry whatsoever about the tool slipping in the collet. Flat spots on shanks can be added to shanks if needed. Best is to follow the Weldon specs and grind a proper flat on the shank.
https://www.hobby-machinist.com/threads/end-mill-holder-vs-collet.21445/

Edit: Weldon flats are very common on heavier duty tooling, like 30, 40, and 50 tapers, and many others as well.


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Here's one you wouldn't mind cutting up a bit. Swiss style, I believe.

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I understand being careful with machinery and cutters is important. I saw this on Craigslist north of Philly, PA for $35.

Thought I'd add a little humor. It looks like it might still function.

I've "modified" 50 year old pristine lathe jaws through carelessness, so I certainly can't be critical.
 
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