Small Vice

[homebrewed]

I have four vises and two of them are the screwless type. The largest of these has 3" wide jaws and is the one I use 99% of the time. The larger 4" Kurt-style is so long that it really hangs over the front of my little benchtop mill. It also is taller so it reduces the Z-axis work envelope a bit more.

The screwless one's form factor is just about ideal for my needs, and, once I learned how to quickly tram it, no big deal to remove and re-install. One pass with the DTI, tap into alignment and it's good to go.

One of my first milling projects was to make hold downs for my vise. I only had to make 3 to get two good ones . I keep the failure around as an object lesson: if you pause work on a project, make SURE you really know what the next step needs to be. Don't assume your memory is correct.

 

[macardoso]

I keep the failure around as an object lesson: if you pause work on a project, make SURE you really know what the next step needs to be. Don't assume your memory is correct.

Whenever I take a break from machining for a month or two and come back, my first two parts will be scrap, no matter how simple or how careful I am. So frustrating.

 

[mikey]

Stefan G did an interesting experiment to see how much vices move under clamping conditions. While he did not test a Kurt vise the information is interesting to think about.

When I need better accuracy, I take the Kurt off and use a screwless vise. When I need the best precision I can get, I take the vise off and clamp to the table. Vises are fast and work well to hold things for cutting but when tolerances are really tight remember that vises move.

 

[GRP]

Thanks for all the replies. I think this is what I'll be using that holiday gift card on. If my wife doesn't spend it first.
Making my own clamps sounds like a great exercise as well.

 

[hman]

I've owned a 3" screwless vise for just about as long as I've owned my mini-mill, and LOVE it. It's almost the only thing I use for work holding (other than clamping directly to the table). +1 on the LMS vise hold-downs. I generally place one in the far table slot and the other in the near table slot. That way, I can move the cross pin to any of the holes. The flat side of the vise allows me to use a machinist's square against the front edge of the mill table and one side of the vise to square it up. OK, not quite as precise as indicating the back jaw, but probably good within 0.001" - OK for over 90& of what I do.

My only "grump" with the vise was the fiddly socket head screw that tightens the cross bar nut. The head of the screw is not a good way to hold things in alignment when relocating the bar. Instead, I put a short length of 1/4-20 allthread in the nut, and use a hex nut at the jaw end. See post #22 at:

Mill Vise Opinions

Personally, I use a modified screwless vise. I tried going to a Kurt style vise, but went back to the screwless after a while because: 1. Deeper jaws 2. Precision ground and parallel 3. Can mount vise on it's side or even on end 4. Wider jaw opening 5. Better at fighting jaw lift 6. It's still...

www.hobby-machinist.com

 

[Illinoyance]

You really want a vise with grooves down the side instead of holes. It makes angled setups much simper. You can clamp anywhere along the groove.

 

[sdelivery]

This style vise is more traditionally used on a surface grinder. They can be used on a mill, but there are some drawbacks. As mentioned in another thread it takes more time to set them up due to the fact that there are no built in anchors on the sides, or keys on the bottom for rough alignment. They are also limited as to the size of parts they can clamp.

Another limiting factor is the amount of holding pressure that can be applied to the part. The part holding mechanism consists of a socket head screw that extends through a rack on the bottom, anchored in a moveable dowel. In most cases the dowel is hardened, but not always.

Here's a link to a picture of the underside of a typical vise. In this case the pin apparently wasn't hardened sufficiently.

Stuart Beam machining | Annoying import screwless vise; the … | Flickr

To me a better choice would be one of this style. This one is only an example of what's available. There are many others of varying sizes.

Exactly. This is a grinding vice not a milling vice

 

[Jim F]

They work with Benchtop mills, just fine.
Some people don't have production needs.

 

[mikey]

Exactly. This is a grinding vice not a milling vice

And yet they are used on Mills the world over.

 

[Jim F]

And yet they are used on Mills the world over.

A local shop has a 7" import, and they say it is the best vise in the shop.
Found that out when I asked about scrap to make one.