On Nov 26, 6:02 am, email@example.com wrote:
Sounds like you may be over tightening your vises. They state 85fl/lbs
or so as the max torque, but the regular Kurt vise generates
tremendous clamping force with very little torque applied. You
shouldn't need more than a speed handle for tightening and breaking
iirc, kurt provides a chart of clamping force -- here's one:
They also have a non-pdf chart somewhere.
Approx 100:1 force, about 1,000 lbs per 10 lbs on the handle.
Funny, tho, 80 lbs does not yield exactly 8 times the force of 10 lbs --
more like 7 times -- but still 7,000+ lbs!
Note the service intervals! I don't think there's a shop on this planet
that does anything maintenance-wise, until the vise jams. :)
I've had to disassemble kurts, to clean out the lead screw hole with a wire
pipebrush, mounted on a drill.
There's sposed to be a plug there to keep debris out, but I've yet to see a
kurt with one intact. I stuff a plastic bag there, altho those black round
plastic inserts for tubing ought to do it, as well. Or a wood plug.
Let me ask you this, have these vises you have observed to move
.001-.002 ever been tightened in the past by hitting the handle with a
plastic hammer? Or been repeatedly tightened by some 600lb gorilla
putting his full weight on the end of the vise handle?
Overtightening can bow the vise base which can tilt the jaw faces
slightly out of parallel, and actually DECREASE the holding power of
the vise, since the full face of the vise jaws are no longer in
complete contact with your part.
Overtightening Kurt vises is unfortunately a more common practice than
it should be. IMO, that's one reason spider handles are better for
tightening than the longer single bar handles. You can't really WHACK
a spider handle without taking a chance of knocking one of the levers
right off the handle.
Repeated overtightening can make the material of the key and keyway
deform enough to sometimes create clearance. Once the process starts
it can only get worse over time if such abuse continues. What needs to
be done in that case is to unscrew the solid jaw, remachine the keyway
in the base AND solid jaw to fit an oversize key, making sure there
it's a light tap fit (not a press fit and not a slip fit).
It appears you're correct, I made an observational error. I saw
the blackness in the poor pictures on the Chick website and made an
incorrect assumption that it was an open area. On a closer view of the
black area I see what appears to be serrated rails that are moved
forward by the internal screw, they seem to have only .5-.75 worth of
travel before they hit the vertical stops.
BUT this brings to light a couple of more possible issues of concern.
1. The jaw movement mechanism seems too clever by half - a lot of
moving/sliding parts that could possibly cause problems. The clearance
between the longitudinal holes the serrated rods run in along the sides
could become contaminated with chips or debris and become hard to move
or at the worst get scored & jammed. The open area around the vertical
clamps that act as a stop for the over-travel of the serrated rails
could get chips or a piece of material caught in/around them which
might restrict the full travel ability and interfere with full closing
of the jaw at a particular position.
2. Chips, debris, material, could get caught between the ratcheting
mechanism and the rack teeth. That "might" interfere with an equal
"pulling" of the movable jaw down, which might twist it slightly out of
3. I also notice from the drawings that the underside has three open
pockets that seem to intersect the screw and rails moving apparatus.
So when the Chick is mounted on a normal T-slotted table, some of those
pockets will be over the T-slots. When I blow off the table after a
job I usually blow the T-slots under the Kurts to clear out the chips.
If that is done with the Chick, it seems that chips would be very
likely be blown up into the pockets that happen to be over the T-slots
that you're blowing the chips out of. Even if you were just blowing
chips from around the outside, there is a possibility that you'll
accidentally blow some chip up in there. I would venture to guess that
chips under there may not be advantageous to the functioning of the vise.
Now it's not known if these hypothetical issues might, could, or will,
surface in actual use, but IMO, they could be problem areas to keep in
See comments above, concerning Chick open pockets over the T-slots.
You've probably not been machining long enough to remember the crude
vises that were used 40 years ago. Even the best of them would be
considered pure junk today. The first Kurts (with their angloc design)
were far and away superior to the old style vises.
Chick and then on a NEW
You've been corrected by three different people now, concerning the
time to drive to San Diego from Saugus. Let me try to put it a
different way, it's about 150 miles. To go 150 miles in 1 1/2 you
would have to AVERAGE 100 miles per hour.
While I don't mind going over 130 from time to time, I don't think I'd
want to try to do 140 MPH on every clear straight away, to AVERAGE 100
mph. Does THAT make it a little more clear now? <g>
I'm going to separate the non-vise related irrelevant chit-chat into
another sub-thread, to try to keep this one on-topic.
>> I said that's what it "looks like". So how else is it held?
> When they arrive you can see for yourself.
The view of the underside of the Chick vise doesn't show any
additional hold-down screws. Are there any?
If not, then that is a definite design flaw, since the solid jaw can
lift under moderate to strong clamping pressure when holding a part at
the top of the vise jaws.
>> How does the ratcheting mechanism work?
> It works well.
Correct me if I'm wrong, but I assume there is a pin/tooth or series
of teeth, that contact the serrated rails to operate the movable jaw.
Now, the contacting tooth/teeth whatever, seem to be retractable by the
buttons on the sides of the movable jaw. That may create a weak link
that might very well be prone to deflection under moderate to strong
clamping pressure. That possible deflection might enable the movable
jaw to lift under pressure.
Also, if chips got between the tooth/teeth that might cause uneven
clamping pressure and affect repeatability.
>> How are the jaws held on?
> When they arrive you can see for yourself.
The jaw holding mechanism seems like it would be a weaker holding
design than simply using two screws.
BTW How are you going to use your Talon Grip vise jaws? An adapter
plate? That kind of defeats the point of the quick release feature.
Here is just one of many sites that have quick-jaw changing tooling
for Kurt type vises.
>> How is the immovable jaw support held to the base, and what absorbs
>> the closing pressure - key? pins? bolts?
> When they arrive you can see for yourself.
If the clamping forces are resisted by pins or bolts instead of a key,
then that further limits the clamping forces that the vise can withstand.
Why have you evading these questions? And why have you tried to
deflect attention away from the vise into other irrelevant areas?
Could it be that you're simply trying to justify your decision in
getting your shop to purchase a Chick vise? Do you think your
management are reading these posts? LOL
The first thing I'd do if I were you, would be to put an indicator on
both the movable and immovable jaws to see how much they move when
clamping a part at the top of the vise jaws. If it's a significant
amount, perhaps you can return the vise for a refund before you run
into other problems.
BTW Did you do your homework and check out these other vises before
purchasing the first one demo'd?
Well variety is the spice of life
Thats what the judge is gonna tell my wife
She said why did you have to do it?, why you such a fool?
I can't resist to try something new..........
--The Doors, Other Voices--circa 1971
I've always attributed it to him just bein plain nuts.
You're correct, YOU are debating.....he's just ramblin aimlessly about
anything to avoid answering your direct questions/concerns about the
Chick Vise. Of course....as usual....he thinks nobody notices
this.....Its what makes him so damn comical.
I gotta admit....I've always found it "interesting" at how sensible
and logical you try to talk to him while he's insanely ramblin and
babblin and slobberin all over himself tryin to get under your skin.
I personally have always thought its just your own personal BOTTLEBOB
way of "gettin all up in his head" just for your own pleasure. Am I
Here's a thought......Since somehow lil jonnie thinks he can make a
round trip from your shop to his in only 1 1/2 hours, why not have him
fire up the ol Saab and come pick you up at your shop and take you to
his shop so he can show you his "broom". Maybe you two can do a lil
"bonding" on the drive back and forth. Don't forget the video
camera......well.....for the rest of us. :)
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