Step Jaws on Kurt Vices?

What kind of step jaws have you found out work best? We use Kurt vices. Lately I've been machining aluminum jaws, but the steps don't last just a log time, but if I reskim them I know they are good and true. Are some of you using hardened step jaws and when you put them on they are always flat?

I use snap jaws step jaws on a pair of 6" kurt double locks.

They are hardened and ground and they work really well. I have no more than .001 variation between the 4 stations.

They are pricey, but they last forever (until you crash anyways). I buy them as needed and have a good collection of sizes now.

Only gripe is the changeover is about the same as regular jaws. Chips can get in the access holes. When you do changeovers it takes time to clean and make sure everything is clean.

+1 for snap jaws. They use short head cap screws that fit in a "t slot" in the jaws. Loosen em up half a turn, pull em out, then throw another set on (they have other options such as vertical and horizontal v jaws with the same setup)

We probably have 30 sets of them, 3/32 thru 1/2, along with vertical and horizontal v jaws, tall jaws, etc.

I would say that they only save a little bit of time over normal jaws. chip_maker is right about chips in the hole and under the jaw - gotta make sure they are clean when you put them in. And give em a good tap down with a mallet after you tighten them all up.

I just make my own Dozen sets at once, quick and easy..

Seriously guys?
I don't mean to be a dick but AL soft jaws milled to a shape is for a few to a little more than a few parts.

Otherwise for a $10 more one can get steel soft jaws made or purchased and then milled to last for hundreds or more pieces.

Sidenote: I absolutely hate SnapJaws!!!

SeymourDumore said:

Seriously guys?
I don't mean to be a dick but AL soft jaws milled to a shape is for a few to a little more than a few parts.

Otherwise for a $10 more one can get steel soft jaws made or purchased and then milled to last for hundreds or more pieces.

Click to expand...

I agree with that too.

I have about 30 blank sets of steel jaws I made in a drawer, ready to be carved out for whatever shape I need, step or otherwise.

I buy 2 or 3 12ft bars of 1 x 1.75 1018, have em cut up when the saw isn't busy, and I throw them on a pallet in a horizontal mill to run while the operator loads a real part on the other pallet. Couple of countersunk holes in the front, and drill and tap the sides for 5/16" screws for stops. Doesn't cost anything more than the material and maybe a minute to load and deburr for a pair of jaws. Although not everyone has a horizontal or the time to make their own I guess.

dandrummerman21 said:

I agree with that too.

I have about 30 blank sets of steel jaws I made in a drawer, ready to be carved out for whatever shape I need, step or otherwise.

I buy 2 or 3 12ft bars of 1 x 1.75 1018, have em cut up when the saw isn't busy, and I throw them on a pallet in a horizontal mill to run while the operator loads a real part on the other pallet. Couple of countersunk holes in the front, and drill and tap the sides for 5/16" screws for stops. Doesn't cost anything more than the material and maybe a minute to load and deburr for a pair of jaws. Although not everyone has a horizontal or the time to make their own I guess.

Click to expand...

Soft jaws don't have to be fancy, all sides don't have to be machined. I use 1x2, and slot the hole and countersink,
only need an 1/8", and then you can flip them over and use the bottom side.. Or when they get used up, you can rip
some material off the top and bottom and get some fresh meat..

As for saving jaws for specific jobs.. Some stuff, yes.. I usually just keep tearing them up until they are done done.

Small sample of jaws that are DONE DONE... and ready for the scrap bucket.


Whats even better is when you can drop jaws out of parts.. Even better when its customer
supplied material.



As for aluminum jaws wearing.. It happens, especially when you don't have much to bite on..
I have a big pile of jaws dropped out of parts, 2024... Night and day difference from 6061,
I'd say they are on par with a mild steel jaw with how they wear.

I make my own, inlcuding HT. Step is .125 and ground with a 2 degree angle, to better grip the parts. Made from D2, If asked I will make sets however you like.

For the most part, I do what others do... knock out half a dozen or more sets of aluminum jaw blanks. I usually use 1" x 2" material, so they are a bit taller than a normal Kurt jaw. When I've used the top side quite a bit I'll just face it to the correct height and flip the jaw over and start using the other side.

I did purchase one set of "ViseCleats" model 120. Fully heat-treated, ground all over, and very accurate. I use them quite a bit, and they are usually what's in my vise if I'm not using soft jaws.

fwiw: (and I'm guessing many people do this) -- any time I'm doing accurate work, I'll disassemble the vise and clean and stone the ground "bed" that the moveable portion slides on, and will also stone the bottom side of the moveable part. On most Kurt vises, it's fairy easy for chips to get under there, and unless that portion carrying the jaw is down flat on the vise, it's common to see the moveable jaw not repeat very well in the Z direction when the vise is tightened. On jobs where I'm looking for max accuracy (if I'm using my heat-treated jaws), I'll actually install the jaw onto the moveable portion outside the machine. I set it up upside-down on the surface plate, and use a tenth indicator to make sure the bottom of the jaw is dead-on flush with the bottom of the moveable slide.

"over the top" ??..... probably, but I don't do any production, so on one-off, very accurate parts, every little bit seems to help.

PM

Depends on what I need. I have old Kurt jaws with a .05" dovetail step, and lots of aluminum jaws. I have had large parts move in aluminum jaws that didn't move in hardened steel jaws so it all depends on what you are holding onto. Keep in mind aluminum on aluminum has a much higher coefficient of friction than aluminum on steel, very helpful when you don't have much to hold onto.

I also make my own soft jaws and love the Snap-Jaw hidden screwhead slots, I just get the bolts from McMaster and make my own. Plenty of times I use aluminum jaws in place of steel with parallels, small aluminum parts hold better and if I touch the jaw making the parts no problem.

We buy a bar of 1 x 2-1/4 1018 and saw it into 6" lengths.
Run a batch of blanks thru the mill to fit both our Kurt and Chick vises.

As for step jaws, I made up 4 sets with a .100" x .100" step, sent them off to heat treat and ground them all flat and alike in-house.
With 4 or 5 vmc's running many different parts a day, the hardened step jaws save on cutting soft jaws by a lot.

dandrummerman21 said:

+1 for snap jaws. They use short head cap screws that fit in a "t slot" in the jaws. Loosen em up half a turn, pull em out, then throw another set on (they have other options such as vertical and horizontal v jaws with the same setup)

We probably have 30 sets of them, 3/32 thru 1/2, along with vertical and horizontal v jaws, tall jaws, etc.

I would say that they only save a little bit of time over normal jaws. chip_maker is right about chips in the hole and under the jaw - gotta make sure they are clean when you put them in. And give em a good tap down with a mallet after you tighten them all up.

Click to expand...

Plug the hole with a piece of disposable foam cut with a punch, that costs a fraction of cent?

garyhlucas said:

Plug the hole with a piece of disposable foam cut with a punch, that costs a fraction of cent?

Click to expand...

Yeah, gonna try something like that one of these days.........