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rotate
08-14-2008, 03:35 PM
I know that many people use screwless vice for milling especially on the smaller machines, but I'm wondering why this may not be recommended. They are precise and have hardened jaws, but are they able to grip hard enough and sustain vertical pulling force? Will the jaws twist under lateral force?

I'm tempted to buy one for my small milling machine so I'd like hear your opinions. Thanks.

http://littlemachineshop.com/products/product_view.php?ProductID=1590&category=3

pcarpenter
08-14-2008, 05:03 PM
We sort of addressed this recently so you may want to do a search. Several folks advised Brian Rupnow not to use one for milling while a few others said they were doing it and it was fine.

I think that if you only have a hammer, all the world looks like a nail.

In most cases a real mill vise has more capacity.

A mill vise can more quickly be adjusted.

A mill vise has detachable jaws allowing for a multitude of shop-made jaws which add all sorts of utility.

These same removable faces help you deal with the inevitable chewed up or marked up jaws.

Many mill vises are of the angle-lock design now days and as such will do wonders for preventing the work from wanting to pop up off the parallels.

These same knock off mill vises are not really all that much more expensive. When the right tool for the job costs about as one with which you can make do, why make do?

Paul

miker
08-14-2008, 05:53 PM
I think this is the thread Paul is referring to ...

http://bbs.homeshopmachinist.net/showthread.php?t=29512

Rgds

Bill Pace
08-14-2008, 06:25 PM
I too agree that a screwless vise is not the best solution for general mill work. While it obviously will work, doesnt mean its the best method.... One of the Kurt clones in the 4" size would be such a better solution -- as Pauls list above points out --- and with a little thought there could be a few more reasons added to that.--. for instance gaining the ability to add the rotating base.

ENCO's version is $69.95, with the base $78.95 ... and, it'll qualify for the free shipping too!!

http://www.use-enco.com/CGI/INSRIT?PMAKA=425-7241

rotate
08-14-2008, 06:31 PM
Thanks for the link Mike. That was a long read but both informative and entertaining.

I think I'll stay away from a screwless vice for milling application. Thanks.

David Powell
08-14-2008, 08:34 PM
I have a screwless vice in work, I really dont know why they bought it, most of the time it sits lonely in our cupboard. However, once in a while it comes in very useful, indeed almost indispensable . I sometimes clamp it in the mill vice at an angle to machine some odd piece and sometimes use it on the surface grinder. Every tool or machine in your shop makes your shop more capable , more effective or more efficient, even those used only rarely. If I ever see a good one on sale somewhere at an attractive price It will follow me home. Regards David Powell.

oldtiffie
08-14-2008, 10:16 PM
I know that many people use screwless vice for milling especially on the smaller machines, but I'm wondering why this may not be recommended. They are precise and have hardened jaws, but are they able to grip hard enough and sustain vertical pulling force? Will the jaws twist under lateral force?

I'm tempted to buy one for my small milling machine so I'd like hear your opinions. Thanks.

http://littlemachineshop.com/products/product_view.php?ProductID=1590&category=3

Hi Rotate.

I have that very same vice from LMS. It is a precision vice. That "angular pull-down" on the moving jaw works the best I've seen. It overcomes all of the "moving jaw up-lift and hammer 'er back down" again problems with other/"normal" vices. Get or make those clamps in the LMS pics as well as they are very handy.

Any chance of a pic or reference for your "small mill"?

I have a range of vices for my mills and will post details/pics in a day or so.

That vice should suit your small mill very well - unless you are anxious to "get into some heavy hogging" and belting the handle on a vice. I am well into NOT doing those things.

It will work every well if you take your time. It is a "Tool-makers" vice which implies that it is for light accurate work.

It is about the only vice that you can leave a job in and stand the vice on its side or end and get very good accuracy indeed for 90 degrees.

That vice is very handy (just right actually) for my Tool & Cutter and surface grinders.

If I want it set accurately for angular use, I don't need a swiveling base for it. I use my digital or vernier protractor (accurate to 0.1 arc degree = 0.0017" per inch but can easily be interpolated to about half of that) off the front edge of my mill table as I know the vice jaws are accurately aligned to the vice ends, edges etc.

If you need better than that, I'd suggest you have a serious look at LMS angle block sets.
http://littlemachineshop.com/products/product_view.php?ProductID=2553&category=

At US$30.00 and with an accuracy of "Accurate to 0.0001 per inch", that is better than 15 times as accurate as the protractors I mentioned. I have a "Vertex" set that has 1/2 deg and 1/4 deg blocks.

This is where this vice shines above all others as you can put the angle block against any side or end face of the vice on the table and use your table "X" or "Y" hand-wheels and a good dial indicator to set those angles very accurately indeed. You can interpolate between "full degrees" by using a good digital calculator and your dial indicator.

Further, not needing a swivel base means that you don't lose space between your work and whatever you have in your milling-head quill (drill, boring head, collets, end-mill etc.).

If I can manage it, I will post some pics of that vice and others on my HF-45 and "Seig" X3 vertical/mill-drills as they are pretty representative of medium and small mill-drills.

In my opinion, just about any small "cheap" vice can do some good work within it limits. I will PM the details to you later.

Even if you buy another vice later, that particular vice will stand you in good stead for when that sort of range and accuracy is required.

oldtiffie
08-14-2008, 11:45 PM
Hi rotate.

PM sent.



In my opinion, just about any small "cheap" vice can do some good work within it limits. I will PM the details to you later.

Even if you buy another vice later, that particular vice will stand you in good stead for when that sort of range and accuracy is required.

Mcgyver
08-15-2008, 12:13 AM
At US$30.00 and with an accuracy of "Accurate to 0.0001 per inch", that is better than 15 times as accurate as the protractors I mentioned. I have a "Vertex" set that has 1/2 deg and 1/4 deg blocks

everywhere i go on the net i read about angle blocks, sine bars, sine plates, etc etc but I've not been able to figure out is the massive disparity between how often someones talking about them and how often they're need. I'm not say nevner, but it is very rare, in my shop anyways, that setting up angle beyond vernier protractor accuracy matters. I've got all that tackle cuz i've been at a while and stuff accumulates, but talk about a low duty cycle - most angle i can remember cutting were for clearance and/or aesthetics

or maybe all you guys are building infantry sighting equipments and I'm just missing the boat - what gives? :D

oldtiffie
08-15-2008, 05:54 AM
Good question Mcgyver.

Answer.

As you say, some are not used all that often - others, surprisingly, quite frequently.

I am in OZ and can't just drive to or call a supplier overseas in the US or UK or from other parts of OZ and get what I need in a day or so, let alone the same or next day.

In some ways its a bit like living out in the sticks and shopping from catalogues - which I suppose it is. So I/we have to try and anticipate needing stuff. Mail to here from the US or UK can take anywhere between a week and a month.

Some of this stuff I use pretty often when I am busy and not surprisingly not all that often when I am not so busy.

I guess there is a lot of impulse buying and "nice to have" in amongst it all too.

Its a "judgment call" as to which is the bigger PITA - having it and not needing or using it on the one hand and needing it an not having it when you need or want it on the other.

As regards the angle blocks. I use them to set something at a required angle on a machine as said. I often use them to set or check a vernier or digital protractor. It might surprise you how often I will find an error. Not always big at all - but too often. If I find an error I will "allow" for it.

I prefer to use an angle block or protractor to set a bevel guage (which can get into some cramped spaces!!) to use on the job as it can take a bit of hard use. This is a really good cheap made in USA item: US$20
http://www.littlemachineshop.com/products/product_view.php?ProductID=3028&category=
And this is a Starrett for which I, for one, cannot justify the additional cost: US$84
http://www.littlemachineshop.com/products/product_view.php?ProductID=2227&category=

I also use the angle blocks to accurately set my swiveling vices.

I have used them to set the angles on my lathe top-slide.

They are as good as a sine bar (and alot easier to use) in many cases.

Angle blocks are the angular equivalent of the straight "Slip Guage" (aka "Johansen/Joe" blocks).

My 6" and 8" "Vertex" rotary tables are pretty good as they are calibrated to 10 arc seconds (0.00005" per inch) for the 8" and 20 arc seconds for the 6" (0.0001" per inch). The accuracy approaches that order.
These are hard to beat too for the money:
http://www.cdcotools.com/item.php?itemid=473

These have come in very handy as they will get into all sorts of places.
http://www.cdcotools.com/item.php?itemid=82

There are heaps of others.

pcarpenter
08-15-2008, 12:28 PM
Mcgyver-- maybe you can answer my question...that relates to the angle blocks.

I always figured (but never tried it) that they could be used as a sort of "parallel" when actually clamping the work. My question is: If you just set your work up with a sine bar or protractor or even one of those really handy magnetic electronic angle gauge thingies, is it safe to put milling machine sorts of loads on work that's therefore not supported underneath, in the vise? I have milled so few angles as not to have to concern myself with it, but I would think that with a heavy cut it would be easy to rotate the part in the vise with potentially disasterous results.

Admittedly, with a part just touching an angle block, you still run the risk of the block getting spit out unless its one of the type where the angle really forms a vee-grove for the (small) work to sit in.

Paul

oldtiffie
08-15-2008, 10:43 PM
Paul,
its quite safe and normal to mount a part in a machine vice tilted at a vertical angle. It can be unsupported in any way other than the gripping force of the jaws.

It is somewhere between possible and probable that when the jaws are tightened that the jaws will be out of parallel either along the jaws horizontally or vertically - or the job can be tapered - all even slightly and they can all add up or cancel each other out or anything in between.

Parallel strips in a vice will only stop the job moving downward - but will not stop it being moved up or along in the vice jaws.

It is the clamping (crushing??) force and friction that stops the job moving.

The more jaw-to-job contact the better.

Put your job in your vice and tilt it as you wish. Put it "hard up" against the fixed jaw but put a couple of strips of paper (newspaper will do) between the moving jar and the job and clamp the vice - slowly - until firm. Now give the vice handle a "thump" with the ball of your hand (use it as a "dead-blow" hammer).

Now try and move the job in the vice, first by hand and then with a soft-faced hammer or a sizable lump/piece of soft metal - phosphor-bronze preferred but lead or soft brass will do. If the job does not move you can start cutting with your mill.

This applies no matter what position the job is in the vice.

If you are unsure of this, try it on a piece of scrap first on the vice on your bench and then on you mill vice.

The vice is always my second option as I prefer to clamp directly to the mill table as I can clamp directly instead of using the vice. You can clamp the job at any angle you like onto the mill table.

Just take it slowly and avoid the temptation to "thrash" the machine or to start "hogging". It is a small mill after all in a HSM environment.

Best of luck and good machining.

If you have a good set of collets and a sharp end-milling cutter and "take things easy" I wouold be very surprised if the job "walked up" in the vice or that the end-milling cutter moved downwards in the collet.

Do make sure that all machine slides "X", "Y", "Z", quill etc. are locked/clamped other than the one you are using for the feeding for the cut/s.

oldtiffie
08-16-2008, 12:09 AM
.................................

..................................
My question is: If you just set your work up with a sine bar or protractor or even one of those really handy magnetic electronic angle gauge thingies, is it safe to put milling machine sorts of loads on work that's therefore not supported underneath, in the vise?
........................................
........................................

Admittedly, with a part just touching an angle block, you still run the risk of the block getting spit out unless its one of the type where the angle really forms a vee-grove for the (small) work to sit in.

Paul

Paul,
are these what you meant?

http://www.cdcotools.com/item.php?itemid=17