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View Full Version : A better vise than the Kurt?



Mcgyver
03-11-2012, 09:46 AM
yeah Dave I was holding out, needed to get some pics. Its not some new style, but new to me, and is impressive.

The new vise is one of these fixed forward jaw arrangements. I bought a new Kurt last year and have liked it a lot, was looking for a second (tired of moving from between machines) when i came across a kijiji guy selling these. He snickered when i asked how it compares to the Kurt....some salesmanship for sure, but he believed it. He says he used to have 70 of them in cnc production shop he wound down. His business now is a odd mix of a job shop and importer from china/taiwan of everything from vises like this to camera stuff. One thing he showed me was a 3' handle - said they they used some as presses and they never complained

As it wasn't immediately apparent to me the action of this vise I took a few pics for the curious. Apparently its a knock off (Taiwan) of some European vise that sells in the thousands. Just saying what i was told.

So far what I like about is deeper jaw than the Kurt, has the same anti-lift feature, through holes in jaws for attaching sold jaws, much more smooth to clamp and undo and the biggest one is the entire area under the work can support things (whereas the centre of the kurt is a no go zone)

I bought it for 250 used, new they're 450. Initially attracted by price I'm impressed with it. I probably sound like shill, I've no interest in it, just kind of impressed with something that is new me. Anyone else use this style or know its pedigree? I will try and get it on the surface place to survey accuracy today....and report on its performace as i get to use it

Base:

https://i.imgur.com/EVDBKAI.jpg

Moving jaw is a the back and part of of this large bar that drops into the channel in the base. There 1/2 a thou play on the indicator

https://i.imgur.com/cPWFle5.jpg

This is the fixed jaw, bolts to the base, straddling the large bar.

https://i.imgur.com/N7RJgHh.jpg

assembled

https://i.imgur.com/kfF9uZ0.jpg

3illmesmart
03-11-2012, 11:40 AM
I just saw photos of one of these and couldn't see how it worked. From your photos, I see how it works, and it looks good. Bet it's heavy.

Arthur.Marks
03-11-2012, 01:12 PM
Sorta looks like a Girardi?
[EDIT:] Perusing through the Gerardi website, I don't think that's it at all. No idea.

oldtiffie
03-11-2012, 01:19 PM
Like here?

https://www.machineryhouse.com.au/Vices-and-Work-Holding

Robin R
03-11-2012, 04:07 PM
I got one from an eBay dealer in Ontario about 4 years ago and really like it. I think I paid about $250 new for it, but the total including shipping was about $400 and that was only because the courier claimed I had a remote address, although I had to go pick it up from the depot.

It's amazingly solid, to get any lift on the workpiece you have to flex the 2"x4" piece of bar the moving jaw is fasted to. I tried it with a 4" wide piece of bar in it and by really torquing on the handle I couldn't get as much as 0.001" lift anywhere.

Accusize in Ontario sells them, though I don't believe that's who I got it from, I think the label might still be on it, I'll see if I can read it next time I'm in the shop. http://www.accusizetools.ca/products_details.asp?big=5&small=36&proid=309 The price in the 2010 Accusize catalogue is $568, so I think got a really good deal even including the shipping.

Looking at the PDF that is downloadable in the link I posted, the current price is $460, which is still a pretty good value here in Canada.

Mcgyver
03-11-2012, 04:12 PM
yeah its general shape of the Gerardi, but different operation. It badged a KR machine vise and distributed by D&R in Oakville....just not sure what they are copying...vendor said its a copy of a Gerardi but clearly its not if you look at the operations

It looks like I won't be using the Kurt as a doorstop quite yet. This thing is a fail, although fixable.

The first test, indicating the bed of the vise showed incredible accuracy. No more than a 1/10 in both directions...impressed after this test

https://i.imgur.com/OEejQRx.jpg

Then I put a square on the moving jaw and indicated it this jaw is fixed to the moving bar so should be dead on . Unbelievably, its out 005"! How can this be - you make a vise with one part to 10ths and then the this? Grrrrr.

https://i.imgur.com/ul6qLpy.jpg

I took the fixed jaw off - its put on very well, the bolts needed a 14mm allen key some real wallops with a big copper hammer to beak. The bottom was carefully checked for burns and worked with an hard Arkansas stone - any high points or burrs would show up bright. Nothing, and the stone polished fairly evenly. No rock when sitting on the surface plate.

I again did the square trick and yup, the vise jaw is .005" out over 6". I'll have to regrind it this afternoon. Being out that much makes it a bit useless and unfixable without a surface grinder, disappointing.

btw, tests done with Starrett A plate, interapid tenths indicator and a mitutoyo bevel square bought new and used only for inspection and handled with a felt cloth

https://i.imgur.com/hFY7yh3.jpg

Check the fixed jaw, its out .003"

https://i.imgur.com/saaGMsE.jpg

Mcgyver
03-11-2012, 06:46 PM
Could it be they're slightly angled on purpose? doesn't make sense as they're angled the wrong way - if viewed from the side its bucket shape instead of keystone.

I figure the only fix was to grind it square. My set up using a block i know is good. Indicated one more time just make sure i wasn't missing something.

https://i.imgur.com/Zk7s1ii.jpg

off to the grinder - gratuitous action shoot. Does show well though how with short overlapping passes one side of the wheel does all the work leaving the other unworn to spark out. Its a fairly light cut, looks like a lot more but thats just the slow shutter speed capturing a lot of sparks
https://i.imgur.com/tdNZoTC.jpg

Finished! Bit of POS imo to be that far out ....and I spent half a day messing with it so probably would have been better to buy a second Kurt lol.

https://i.imgur.com/QUaoyG3.jpg

Black_Moons
03-11-2012, 07:27 PM
How on earth do you measure the knife edge of that square with a round indicator probe? Im glad you used a second square block.

Also I suspect the only reason you spent a day messing with it was because it intrigued you by its design and you wanted to mess with it :)

Intresting design, athough it seems strange to me to use the screw in compression and not tension, as well as having the excessive screw stickout when its open wide since thats about where I stand to operate my mill.

you could consider adding gibs below the fixed jaw to secure the movable jaw from any float whatsoever. Athough that large metal chunk likey helps pull the jaw down by sheer weight, as well as the fact the screw is in line with the jaws.

If the jaw is outward, Maybe its because of 'they used some as presses' and it has been sprung, Just like a lathe chuck!

Dan Dubeau
03-11-2012, 08:10 PM
We've got a couple like that at work, among the Kurt's, and Kurt clones. The do a good job of holding the shelves down.....

Guys just prefer the Kurts (myself included). They are pretty beefy though. I've never checked them for square, and now you got me curious.

hardtail
03-11-2012, 08:32 PM
Whats on the floor with the crankshaft beside the brake?

JoeLee
03-11-2012, 08:38 PM
How on earth do you measure the knife edge of that square with a round indicator probe? Im glad you used a second square block.

Also I suspect the only reason you spent a day messing with it was because it intrigued you by its design and you wanted to mess with it :)

Intresting design, athough it seems strange to me to use the screw in compression and not tension, as well as having the excessive screw stickout when its open wide since thats about where I stand to operate my mill.

you could consider adding gibs below the fixed jaw to secure the movable jaw from any float whatsoever. Athough that large metal chunk likey helps pull the jaw down by sheer weight, as well as the fact the screw is in line with the jaws.

If the jaw is outward, Maybe its because of 'they used some as presses' and it has been sprung, Just like a lathe chuck!

You beat me to it, There must be some kind of trick I'm not aware of to be able to ride the ball of that indicator down the knife edge of the square.

JL................

JoeLee
03-11-2012, 08:41 PM
I just saw photos of one of these and couldn't see how it worked. From your photos, I see how it works, and it looks good. Bet it's heavy.

I never saw a vise like that either. The front jaw is fixed and the rear jaw moves back into it along with the center body of the vise. !!!!! ????
I don't know if I could get used to it, it's ass backwards, definitely not Kurts design.

JL..............

John Stevenson
03-11-2012, 08:42 PM
So far what I like about is deeper jaw than the Kurt, has the same anti-lift feature, through holes in jaws for attaching sold jaws, much more smooth to clamp and undo and the biggest one is the entire area under the work can support things (whereas the centre of the kurt is a no go zone)



I was under the impression the Kurt anti lift was by an internal wedge inside the moving jaw ?
Don't see that design on this one. ?

Mcgyver
03-11-2012, 08:45 PM
You beat me to it, There must be some kind of trick I'm not aware of to be able to ride the ball of that indicator down the knife edge of the square.

JL................

you don't, you just sweep it slowly over each end, with it barely touching, and note the high points. Use a small sq to make the sure the big sq is sq, ie vertical to the plate.

BM, the only way plastic deformation would account for the test results would be if the 2" piece of tool steel was permanently forced into a trapezoid shape. I don't think that happened, the force would be more than you could impart and I'd say keys and bolts would have bust first

Mcgyver
03-11-2012, 08:49 PM
I was under the impression the Kurt anti lift was by an internal wedge inside the moving jaw ?
Don't see that design on this one. ?

sorry, didn't mean the mechanism is the same as the angle lock, just the result. The way its set up the moving jaw is pulled down tightening.

lazlo
03-11-2012, 09:40 PM
Finished! Bit of POS imo to be that far out ....and I spent half a day messing with it so probably would have been better to buy a second Kurt lol.

That's the spirit! :)

Arthur.Marks
05-25-2014, 06:02 PM
OLD THREAD REDUX
Sorry to raise the dead, but this thread popped up in an image search for something totally unrelated. I have the answer to the origin of the copy: Gianni Suffriti (http://www.giannisuffriti.com/photo.htm), an Italian manufacturer. That's the origin of the design. I learned of them from Ceriani (http://www.cerianimu.com/en/), which sell them for their Italian manufactured milling machines. Carry on... :o

DR
05-25-2014, 06:32 PM
I wouldn't think the moving back jaw would be popular at all. It's pretty much standard on CNC machines to reference off the stationary (back) jaw of a vise. This vise would not mix well with the more common Kurt and Kurt clones. Gcode programs would not interchange between machines.

The other major issue is the non-replaceable jaws.

Jaakko Fagerlund
05-25-2014, 11:55 PM
I wouldn't think the moving back jaw would be popular at all. It's pretty much standard on CNC machines to reference off the stationary (back) jaw of a vise. This vise would not mix well with the more common Kurt and Kurt clones. Gcode programs would not interchange between machines.

The other major issue is the non-replaceable jaws.
And if you want a better vise for CNC operations, take a look at Quad-I (Quad-One). Nice design and really nice for the operator.

Paul Alciatore
05-25-2014, 11:58 PM
I don't see how the movable jaw is pulled down in this design. It just has no way to move up. The forces when tightening it actually do tend to move it up (draw a side view and add the force vectors if you don't believe me). The long, sliding base that it is attached to makes that almost impossible.

The reason for jaw tilting is because most movable jaws tend to rotate when the vise is tightened.

http://bbs.homeshopmachinist.net/attachment.php?attachmentid=1444&d=1500316144

This is what the Kurt design is fighting. With this vise design, the length of the sliding base and the fact that it goes under the fixed jaw, probably with little clearance, both prevent it from rotating and hence from the movable jaw from lifting.

I like this design. It really is quite clever. And it occurs to me that it could be constructed from flat ground stock held together with SHCSs. Might make a good construction project. Oh heck, one more thing on my to-do list.




sorry, didn't mean the mechanism is the same as the angle lock, just the result. The way its set up the moving jaw is pulled down tightening.

Sun God
05-26-2014, 01:30 AM
If you assume the bottom of the fixed jaw acts as a fulcrum, and the screw imparts a slight upthrust to to the outboard end of the movable jaw, then a downward thrust of the fixed jaw onto the bed of the vise is inherent - it would work like a screwless toolmakers vise, just using a long lever to reverse the direction of thrust input :confused:

John Stevenson
05-26-2014, 07:15 AM
Model Engineering services who used to market the Dore Westbury milling machine used to also market a vise for them.
because the milling machine was small, about the size of the mini mill with long table to vise was also small, 2" jaws from memory but it was made to open up to 4 or 5 inches to be a general hold anything vise.

The moveable front jaw had a tongue that went under the fixed rear jaw to stop it lifting.

They were a very useful vise with about the only drawback being the tongue that stuck out.

Then I built mine I fitted a longer tongue so it went under the nut and fixed jaw to make it even more rigid.

http://www.stevenson-engineers.co.uk/files/dore%20vise.jpg

Don't have a photo of mine but found this one on the web with credit to Ian Morris.

Paul Alciatore
05-26-2014, 05:58 PM
???

The fixed jaw is the one in the middle. The moving bar travels under it and has the movable jaw at it's back end and a moving, threaded upright at it's front end. The moving bar travels between the base and the fixed jaw. It can not go below the base and it can not rise up, into the fixed jaw. So it is constrained to move horizontally (front to back) only.

The screw is used in a compression mode so it is pushing the fixed jaw to the rear and the threaded upright to the front. The only way that force tends to rotate the moving bar is if you consider it to pivot on it's front, bottom edge and that rotation would tend to lift the movable jaw. Any slop between the moving bar and the fixed jaw's bottom would allow this rotation and the movement would be amplified at the rear in proportion to the two distances from the front edge pivot point. If the vise is well made with little allowance/tolerance in the fit at the bottom of the fixed jaw then this upward motion of the movable jaw would be very small, perhaps only a thousandth or two.

However, it will be hard to get the movable bar to actually pivot on that front, bottom edge. It will more likely just slip forward, drawing the rear, movable jaw with it. So I would expect very little lift of the movable jaw. It will probably flex more than lift.

As I said, I LIKE this design. It avoids instead of fighting the problem of jaw lift. If I had the time I would start building one now. But other priorities are more urgent.



If you assume the bottom of the fixed jaw acts as a fulcrum, and the screw imparts a slight upthrust to to the outboard end of the movable jaw, then a downward thrust of the fixed jaw onto the bed of the vise is inherent - it would work like a screwless toolmakers vise, just using a long lever to reverse the direction of thrust input :confused:

Mcgyver
01-14-2018, 02:06 PM
I just changed the photos in this away from the evil photosuckit so thought I'd give it a bump as a pat on the back :D :D

I've since replaced it with another Kurt. Not because of its performance, but 1) on the horizontal mill I want stuff as close to the column as possible (this vise takes it in the other direction) and 2) there times when have two matching vises is just the thing

Dan_the_Chemist
01-14-2018, 10:47 PM
So, what did you do with it? Is it holding your boat on station?

Mcgyver
01-15-2018, 08:01 AM
Its keeping a bench held down.....either need to sell it or buy another mill

Paul Alciatore
01-15-2018, 06:40 PM
So you have TWO Kurts?

"YOU SUCK" is not strong enough for that.

PS; I also replaced a non functional Photobucket link in my post above.




I just changed the photos in this away from the evil photosuckit so thought I'd give it a bump as a pat on the back :D :D

I've since replaced it with another Kurt. Not because of its performance, but 1) on the horizontal mill I want stuff as close to the column as possible (this vise takes it in the other direction) and 2) there times when have two matching vises is just the thing

Mcgyver
01-15-2018, 06:56 PM
So you have TWO Kurts?

"YOU SUCK" is not strong enough for that.


lol, 3 if you count the D30.....and a D20 is now parts on the bench, or maybe I should call it Mc20 to avoid legal action lol. Thought of making a Mc10 as well. The 2nd Kurt is semi-borrowed semi-permanently from work where fabrication has taken off and machining is all but dead.

jhe.1973
01-16-2018, 02:05 AM
Thanks Mcgyver for the bump. I wouldn't have seen this otherwise. Thanks also to you and Paul for updating your photos. Its tedious, but makes searching older threads so much more valuable!

http://bbs.homeshopmachinist.net/attachment.php?attachmentid=1146&d=1492446272

Dan Dubeau
01-16-2018, 08:24 AM
I think the ones we have at work like that are probably still in the same spot they were when this thread started. Only now I've got one at home that's holding down my floor. I think I paid ~$30 for it at an auction. I don't know why, I probably could have got one from work for free, but auction fever stuck me I suppose. I do have a new bigger boat this year, so maybe an anchor upgrade is in order....

ulav8r
01-16-2018, 09:38 PM
What a shock, clicked to sell first unread message, it took me to post #22. Did not expect a new pose from Sir John. Had to scroll down to find the first new post.

CCWKen
01-17-2018, 10:09 AM
Yep, he's with us all the time. Thought I heard something moving things on my bench the other day. Walked out of the lathe room thinking the BIL came to the shop but nothing/nobody was there. Kinda creepy. :eek:

dave_r
01-17-2018, 04:12 PM
That was just the invisible person hiding the tools you put down.