Question: Positioning Vise

[henningssom]

Hi,
I bought a positioning vise. It works great but I think the rubber cushion is too soft. I get too much vibrations while working. It is really irritating and I was wondering if I could buy a harder one somewhere. I have looked at GRS but have not found anything there. Is there anything else I can do?
Mike

 

[Brian Marshall]

Mike,

You've got no location in your profile. That makes it possible that you live in a part of the world where my advice might be useless. I went and looked it up on your website.

Is the vise a GRS positioning vise? If so, how did it get separated from it's original hard rubber base?

Can you put up an image and describe it a bit better? "Cushion" does not sound right... and yes, I realize that you may have chosen the wrong word?


The simple solution to replacing the original base - where I live, would be to go down to a farm supply or one of the bigger hardware or tool supply stores and find a solid rubber dolly or lawn mower wheel.

Having never been to Sweden I don't know if you have that choice? They are what the GRS "factory" uses for bases, but I am fairly sure they buy them in bulk, not mounted to the wheel.

The solid rubber tire is put onto the steel rim while hot and flexible. You simply put it in hot water to pry it back off. Boil some water in a pot and drop it in.

Use a very large screwdriver to pry with when it gets hot. You will also need gloves for your hands.


Another option would be to turn one on a lathe. Wood, Delrin or other dense materials will work.

Then, depending on the freedom you need to tip your vise - you can glue thin felt or even just put a towel between the block and the ball vise.


Brian

 

[sam]

Hi,
I bought a positioning vise. It works great but I think the rubber cushion is too soft. I get too much vibrations while working. It is really irritating and I was wondering if I could buy a harder one somewhere. I have looked at GRS but have not found anything there. Is there anything else I can do?
Mike

Man, what are you engraving that the Positioning Vise would vibrate? That thing weighs a ton. You can flip the rubber tire over so the vise rests directly against the rubber and not the nylon pads. Maybe that'll help you.

 

[henningssom]

Brian,
Thanks for your answer.
Yeah right rubber base it is then. Didn't know what to call it. I do have that one. I just got it and this is my first engraving with this new vise. I have used the micro block since I started four years ago so I am use to working with that. I guess I just have to get use to this one but I do think because it is quite high, I might have to look for a harder rubber ring.
Thanks,
Mike

 

[henningssom]

Man, what are you engraving that the Positioning Vise would vibrate? That thing weighs a ton. You can flip the rubber tire over so the vise rests directly against the rubber and not the nylon pads. Maybe that'll help you.

Hi Sam,
No I just tried that.
I think because it weighs a ton, the rubber base is too soft and should be harder.
I tried your low vise at the ICCE in Kansas City and liked that one.
However I don't have that table so I could fit a rotary disk. So I bought this one instead. It is great but I need to fix this issue.
Mike

 

[monk]

vibration ? are you engraving thin material ? if so, clamping alone is not the answer. the piece should be backed up with t-loc, hot melt, or pitch/shellac. backing up like this transmits the vibration further down into the vise where it does no harm.

 

[oiseau metal arts]

what is the vise sitting on? (not the rubber base) there is no way the base is soft enough to cause that much vibration. if you are using one of the GRS shelves without anything under to support it, then that could be where the vibration is causing the issue. if not on one of the GRS shelves, then whatever it is on needs to be solid and well supported.

 

[henningssom]

Okay so here is my vise. I did some tests yesterday and found out that it has to be that rubber base. Once I removed it and placed the vise directly on to the platen, it became rock solid. I will try to fix something else, a hard base like wood or plastic of some sort. I ll let you know how it goes.
Thanks,
Mike

 

[oiseau metal arts]

looks like you have something under the base. foam pad of some sort.... its also not sitting solid in the shelf. you have it on the bent up corners rather than sitting flat on the shelf. that could be a more likely source.

unless GRS has changed what they make their bases out of then you are just as likely to get vibrations if it was made of wood. that would just be a minor fix to what the actual problem is.... the shelf isn't big enough for the positioning vise to shift. look into a different set up where you can have the vise and its base sit flat down on something. the drill press stand idea is a popular one. look through this thread for some ideas.
http://www.engraverscafe.com/showthread.php?1511-Workbench-thread&highlight=drill+press+stand

 

[JMiller]

Securing your bracket with nuts and bolts instead of vise-grips will help reduce vibrations as well.

 

[henningssom]

Guys, well i do have a flat sanding stone under the base but that is so I can come up over the bent corners and turn the vise when it is not centered. However that is not the issue, I have tried without.
The bracket, I have one bolt on the left side (showing in the picture) The funny thing is that the holes doesn't line up with each other. It is hardened steel so I couldn't drill new ones. But this is not the problem either. I have tried without but the same result.
Maybe it is just me, perhaps I need to get use to working with this vise.
If I come up with something, I will let you know.
Thanks,

 

[Dave London]

A 4 inch PVC or ABS closet flange or coupling would make a rigid base YMMV

 

[Andrew Biggs]

It’s like the neighbours dog barking. Once you key into it……….. it just annoys the bejeebers out of you.

I find it hard to believe that it’s the rubber ring. With all that mass and weight of the vise to get through the vibration should be non existent. Even if you are using a hammer and chisel and pounding the hell out of it.

I use a low profile vise very day and occasionally a magnablock. Both have rubber rings like all the GRS vises and vibration has never been a problem with them. Even the micro block is vibration free.

Have you tried a few experiments with the vise still in the rubber ring………like putting it on your solid bench top or floor. It may well be the shelf setup you have it on. Another possibility is that it’s whatever is the backing to your knife.

Before buying or making a new base I’d be looking at everything else first because something isn’t right.

But then again…….sometimes the planets align in such a way that weird stuff happens

Cheers
Andrew

PS. I can see this being a great Myth Busters episode on TV

 

[henningssom]

Okay so I have tried just about everything but here is the deal.
The vise does not vibrate once I turn it with my left hand and cutting with the other. However every time I switch grip or just the slightest touch on it it will vibrate. Okay I have this reptilian brain but I think because it is a very high vise it becomes very sensitive. The weight is good but for me with a wooden floor it is more unified with the whole house. Now I know when my two year old daughter sneezes when she is playing with the neighbor next door. I think a concrete floor would help a lot. The height, can't do anything about that but it explains why GRS made a low vise. I also got some good advice from Josh at GRS on how to fix my platen to the desk. As it turns out I am missing a piece on that.
All in all it is a good vise and I am very happy about it. Thank you guys for all the help you have given me.

 

[Southern Custom]

I'll just throw this out. Is it your vise that is vibrating or the piece you are trying to cut. If it is the workpiece then I'd suggest taking a close look at the way you fixture it. I noticed you are using the gray thermoloc. I had a conversation with another engraver recently about the fact that thermo lock will often act like a trampoline. You need a solid connection with the vise using as little thermo lock in the fixture as you can to get the job done. If it's too thick it just bounces.
I may be totally off base but this may help.
Layne

 

[Andrew Biggs]

The vise does not vibrate once I turn it with my left hand and cutting with the other. However every time I switch grip or just the slightest touch on it it will vibrate.

It sounds to me as though it is your mounting system/platen that is the problem. Not vibrating but rather shaking. A wooden floor with no extra support will also make that happen as it acts like a spring board........I had to crawl under the house and reinforce that part of the wooden floor in my studio. It cured about 90% of it but not 100%

I doubt very much if it has anything to do with the height of the vise. The sheer weight and distribution of the mass would simply not allow for it.......you have a huge weight being supported by a thin metal rod on a wooden floor. So all of that weight and mass is being centred into a relatively small area instead of being disbursed over a wider area.............That is where I would be looking for answers.

Cheers
Andrew

Also, is your bench free standing or secured to walls and floor. That will contribute to the effect you are getting. Is it a heavy bench or light bench, again, this can contribute toward what is happening.

 

[Lonestarr]

Hi Mike First of all you have some outstanding knives on your website, very nice.......Having had many years of experience in alignment and balancing high speed rotating equipment brings back memories of impossible problems of vibrations that should never have happened.....I would suggest that you move out side on to a concrete pad with a sturdy table and try to bring back the offensive vibration....You may find the floor in your house is resonating with the small noise from the engraving process....There is nothing like dead weight to get rid of resonance and harmonics in anything that needs to be vibration free or as others suggest use a soft rubber cushion tire to isolate your vise from your table or floor...
Let us know what you find, first I have heard of unwelcome vibration in engraving...

good luck Bob

 

[James Ashley]

I had the same problem with my vice. Turns out it was my holding fixtures. I was using the thermoloc the same way you are (very bad). I came up with a pretty good solution but i will have to post when i get home from work this evening.

 

[Barry Lee Hands]

Use a piece of round steel well casing pipe.

 

[henningssom]

Barry, Im not really sure on what you are talking about but I guess I figure it all out in time.
Here is what I am doing right now.
To be continued.
Thanks for all your advices!