Building a small Machinist Vise

[kizmit99]

So I've decided I'm going to build me a small "screwless" machinist vise. I know I could just buy one for fairly cheap that would be a lot better than what I can build in terms of precision, hardness, surface finish, etc - but I decided, what the heck, I'll give it a go anyway. If I screw it up, I can always just buy a replacement...

I know this wouldn't be a challenge for many of the members here, as I'm definitely in the beginner camp, but figured I'd share the process anyway. I know I'll have questions (already have) and who knows maybe it'll help someone else out at some point... Anyway, here goes...

I started with some plans from another site for a small machinist vise. On a whim I had also bought some 1x1.5 12L14 bar off ebay, so I figured I use that. The plans had the base and fixed jaw of the vise machined out of a single hunk of steel. Just given the size of the bar I had to work with, I was going to need to make the fixed jaw out of a separate piece. Here was my original idea:



BTW - another post on this site turned me on to the eMachineShop design software - very cool, very easy tool...
Anyway, I figured the step in the back of the fixed jaw would help to lock it into position, then a couple of cap screws would secure it to the base. I've since changed the design and replaced that step with a groove and a matching tenon on the fixed jaw to lock them together (see next pic). That change allowed me to keep the full 1" thickness of the base. I've also been toying with various arrangements for the adjusting bar (which the movable jaw pulls against). Definitely haven't settled on a design for that yet. In this pic I've got a different approach for the adjusting bar which wouldn't require completely removing it to adjust the opening.



I am a little concerned that this approach removes too much metal from the base and may introduce too much flexing? With this approach the base basically becomes a hollow box with four 1/2"x1/4" legs. I'm sure it would be plenty strong/stiff for what I need, just wondering if there may be a better compromise...
Enough with the design, on to starting the build...
I began with a slighter longer than 6 inch section of the 1x1.5 bar, supposedly 12L14...



I set to squaring it up on my mill (G0704):



This is when I began to suspect that it wasn't really 12L14. I've used 12L14 on my lathe before and it always turned and cut like butter. This stuff cut like, well, steel. Not sure what it actually is, but I'm pretty sure it's not 12L14...
All cleaned up:



I then cut the jaws from this piece and squared up all the ends:



Here's the slot in the base, with the tenon on the fixed jaw fitted:



I had some DRO issues while laying out and cutting the slot and tenon, so the back of the jaw isn't flush with the back of the base. But that won't hurt anything. I also had some fitment issues with the tenon. The inside corners of are not getting milled out cleanly. It's like the end mill has a very slight radius at the edges, so the inside corners are very slightly rounded. To fit the fixed jaw I ended up relieving the outside corners slightly with a file. Would this be considered normal? The plan I got for the vise (and an actual manufactured screwless vise I have) have relief cuts on the inside corners, almost as if the corner was drilled out prior to be milled. Is there a trick to this that I'm missing? Any pointers would be welcome. Relieving the outside corners was fine for that piece, but I've got a similar issue with the slots and groove I cut for the movable jaw:



Before I bevel the outside corners here, thought I would ask for suggestions on ways to relieve the inside corners...

I'm happier with the fit of the movable jaw, it has just a few thousands clearance and has no noticeable "play". Other than the fact it doesn't sit all the way down, it slides and fits quite well.

Anyway, this is as far as I've gotten so far. Hope this doesn't bore anyone to tears...

 

[Andre]

Looking good, here is some food for thought:

http://www.deansphotographica.com/machining/projects/mill/vise/vise.html

 

[Don B]

I'm not sure how far along you are or if you'd want to incorporate something like this into you design but just something to think about, I have 2 of these toolmakers style vises and the one in the picture is so much nicer to use because the jaw can be moved/repositioned without the need to remove the pin.

Sorry not a great picture, the spring at the back end of the jaw keeps the pin in place but a little downward pressure with the allan wrench allows the jaw to be moved, if you want more detail just let me know and I'll provide it.

 

[kizmit99]

Thanks Don - I have a 3" vise similar to the one you've shown. I think that approach is probably the best because it allows easy adjustment of the rear jaw, plus allows some 'meat' between the holes along the sides. At 1.5" wide I think there would be plenty of room for that arrangement if I didn't cut clamping slots into the sides (not shown in the first model). I am interested in having those slots though. If the pocket on the bottom is .75" wide, that would only leave .375 on each side, mill a .250 clamping slot and I'm left with about .125 on each side -- probably enough, certainly better than nothing I guess (like in my second model). I'll have to try modeling this in eMachineShop and see if I can squeeze everything into the available space...

 

[Rick Leslie]

This is an excellent project for a 'beginner' as you say. It's not very complicated but does require though, planning and attention to detail All great exercises for a budding machinist. And I use Emachineshop almost exclusively although I'm certainly no pro at 3D modeling. In fact, I'm about as far from it as one can get.

That thread helped me more than any class, book or youtube video.

Here's some more commentary on the program for your entertainment.
http://www.hobby-machinist.com/showthread.php?t=7988&highlight=cnc+modeling

 

[Don B]

Thanks Don - I have a 3" vise similar to the one you've shown. I think that approach is probably the best because it allows easy adjustment of the rear jaw, plus allows some 'meat' between the holes along the sides. At 1.5" wide I think there would be plenty of room for that arrangement if I didn't cut clamping slots into the sides (not shown in the first model). I am interested in having those slots though. If the pocket on the bottom is .75" wide, that would only leave .375 on each side, mill a .250 clamping slot and I'm left with about .125 on each side -- probably enough, certainly better than nothing I guess (like in my second model). I'll have to try modeling this in eMachineShop and see if I can squeeze everything into the available space...

No problem, your welcome, sure I see what you mean about the slots, the one vise I have just has holes, I'm not that fond of that arrangement the slots are better, what about 3 separate slots, say leaving a web every third or fourth hole, you could still use a normal clap and get the benefit of a pin that slides...?:thinking:
Just a thought....)
Looking good though.... Good work..........)

 

[spindle]

Nice job so far! I also making me a small vice but more "a la Taig" concept as the movable jaw can be tighten to prevent it to rise up. It is mostly made out of Al 6061 as my mini mill will refuse to cut steel! I now have to make myself a ACME tap. Another project. I will also line the jaws with brass. Keep us posted on the development.

 

[kizmit99]

I modeled the "open bottom" locking model with clamping slots and I definitely like this approach better than either of my original ideas. There seems to be plenty of metal 'webbing' between all the cut outs, which should tie everything together nicely and keep the overall block pretty solid. Here's the model (it's kind of difficult to get a static view that shows everything well)...





With that settled, I decided to go for it. I started by center drilling for the through holes, then drilled them out with 3/16" bit, then followed with a 1/4" bit.





That was as far as I got yesterday. Whatever this bar is made of, it's definitely not 12L14. I chipped a cobalt bit while drilling it, luckily I got a Drill Doctor a while back. A quick resharpen and it was back in business.

Tonight I milled out the clamping slots:



Here's how it's looking at this point:



Just have to mill out the center section (top at 3/8, bottom at 5/8) and then I can move on to the actual locking mechanism and the movable jaw...

Thanks for the comments and suggestions so far - they've definitely helped rework the design.

 

[spindle]

Wow that is going to be one solid vice! I'm following this. Great work

 

[kizmit99]

More progress...
I milled the center section out:



a .375 slot from the top, and .625 slot from the bottom - meeting just about .010 above the center line of the cross-holes...



I drilled the mounting holes in the base for the fixed jaw, carefully transferred the positions to the fixed jaw, then drilled the holes in the fixed jaw. The holes in the jaw are off by about .050"....



I thought that maybe they would be "close enough" so tried tapping one - Nope, aint gonna work...
Next step appears to be remaking the fixed jaw...