How flat and parallel are the sides you are clamping on?
Hey All,
I'm having a bit of a problem with a toolmakers vise that I recently purchased . I am new to this type of vise and have chucked it up to inexperience- hope I am right. I've attached a picture illustrating the problem I am having. The clamping force of the vise doesn't seem to be enough to hold the workpiece in place properly. The 1-2-3 block was used to orient the block so that it ends up being square. I had several block pull out like this one, facing the top of the block, .060" DOC with a .250 4 flute - 12ipm feed @ ~ 4000 rpm. I'm putting about all the torque I feel comfortable with on that clamping screw...
What's wrong?
Thanks,
Adam
How flat and parallel are the sides you are clamping on?
Your most likely bottoming out the screw used to tighten the vise and not actually clamping the material. You either need unscrew and index to the next slot or put a piece of material in-between for added width.
Andre' B;
The blocks were cut from an extruded square. When they were mounted in the vise, the raw, un-machined sides were put into the vise.
The fit and finish on the toolmakers vise seem to be very good but I haven't taken an indicator to it yet.
mmprestine,
I don't believe I am bottoming out the screw, but I do think I am 'inbetween' two of the slots. The far slot is a tad to far. The near slot works, but points the screw and a steep downward angle. Adding a piece of material could alleviate the problem. Thanks
First off this type of vise is made for a surface grinder they were not intended to be used as mill vises. If you want to use it on a mill you have to clamp it as tight as you can get .and take light cuts . Use a small tool the larger the tool the more the pull force on the part. I would use a 6 inch long allen wrench , and baybe a little bit of cheater pipe....Good luck
And use the "farthest" slot possible. That pulls the jaws together more than down into the base of the vise.
With these vises you have to make sure that the bolt you tighten is at a low angle. Which usually means loosening that bolt such that the arm with the cylinder can move forward one more notch. And then tightening it from there. If the head of the tightening bolt is pointing more upwards thats usually an indication that you need to move the cylinder one more notch forward.
This is one of those things that's hard to explain in words if I was at home I would take a picture or make a short video to explain it.
Two other things use a soft faced hammer (dead blow, brass) to tap your stock flat. And always check it by hand to make sure it's being held properly before cutting.
One problem is you have your clamp screw at too high an angle. Once it gets near 45*, half of the clamping force is applied downward. Buy a longer bolt so the movable jaw is pulled into the part, not down into the vise. Also, a dowel or ball bearing placed between the jaw and part will help if the block is an odd shape. Last, you are taking too big of a cut. 1/10 of what you are trying to take is a better depth of cut (DOC).
gabedrummin,
Interesting- I didn't know they were intended for grinding.
MrWild, allenj20, WaveDude
I completely understand what you guys are saying- just graduated with an ME degree
Okay... let me also explain that I started cutting these blocks on my 4" import vise, something like this: http://littlemachineshop.com/product...ory=1963256912
I had an indicator on the clamping jaw. It didn't seem to be lifting, but it didn't seem to sit flat either, even though the soft jaws were cut while the jaws were clamped down.
When I switched over the the toolmakers vise, I started getting a much better finish and didn't have a worry about the one end lifting. I like everything about it, except the apparent low clamping force.
So now that I'm starting to understand the subtles that surround vises, I think I am ready to spend some money on something with quality. I'm looking for a vise that can be turned on its side such as this one:
http://littlemachineshop.com/product...ory=1963256912
I understand glacern makes a good vise but I don't see a 4" that I can turn on end. What are some other suggestions?
Thanks for all the help guys- love this forum
Adam
PS: I'm also searching past threads now, as I know this has been brought up many times in the past.
Many Members / Machinist use those vises every day with great results. There for more than just grinding..
Here is how I square/tram my vise up and prepare it for use.
Step 1 : I decide what whole the pin on the vise that tightens the jaws has to be in to determine where ill use3 my hold downs.
Step 2 I use these hold downs. I put them far enough away from the work piece as I can so it dose not interfere with my parallels or work piece.
http://www.littlemachineshop.com/pro...ory=1963256911
Step 3 : I take my vise and snug my hold downs up barley just so it isnt flopping around. I mount my vise the opposite way than you do. I have the top of my vise facing the column. Because Ill take the vise while its snug and bring the vise up against the column with a Parallel in the middle of the two.
If Im doing something quick and it dose not need to bee 100% dead on I just tighten down my hold down with the Vise then parallel and column all touching being nice and snug.
This brings me very close to being squared up . But If it has to be dead on then Ill Go one more step and before I tighten my hold down I pull out my dial test indicator. When its all trammed then ill tighten the hold downs.
Here is a video to show kinda what I mean another member made it . It should get you in the right direction.
Also if its important that every thing is perfect and square you'll need to tram you mill also.
http://www.vimeo.com/12186798 <------- Vid
If you have the money though a Glacern or Kurt or clone would be the best option .
Also are you starting your cut on the top at the point or the middle ?
It looks like the middle and depending on machine you probably should be taking your cut on the very top first where the point is.
Try taking a smaller cut dont try taking all the material off at first.
The best accessory for a vise is a deadblow or a soft faced mallet.
http://www.wttool.com/product-exec/p...t_Face_Hammers
Even with lock down vises it's a good idea to smack the part down into the vise after clamping to ensure it's flat
against the bottom or the parallels on all 4 corners.
An accurately flat vise bottom will make better parts.
I have a 6 inch version of the new LMS vise and it pulls the jaw down as it tightens.
http://littlemachineshop.com/product...ory=1963256912
Grips the part better than the other machine vise but I still give it a whap to make sure, just habit now after 30 years.
Hoss
http://www.hossmachine.info - Gosh, you've... really got some nice toys here. - Roy Batty -- http://www.g0704.com - http://www.bf20.com - http://www.g0602.com