# Stain prevention under mill vise



## petertha (Oct 12, 2020)

Thought I would post this question here because maybe some of you have some insight for both stain removal & prevention. 

I have a relatively new Taiwan mill. After removing my Bison vise (similar to pic) I noticed some slight discoloration on the CI table corresponding to the vise foot print. I don't use flood coolant but do use oil based cutting fluids & occasional squirt of way oil on the screw & vise slides. First couple times it was barely noticeable & came off with a soft scuff pan & WD-40 or mild petroleum based degreaser. Now it seems a bit darker & somewhat more persistent. Might have been there for a longer period over summer or also more use, not sure. Its like a tan color stain, not really corrosion. Its not really hurting anything... but my eyes. LOL

I've heard of coating products that you can spray on that prevent stains & corrosion, but I'm not sure a film of anything between the vise & table is a good idea?

The other thing I was wondering - I've been using this natural cutting oil more recently. It doesn't irritate by skin quite as much as Tapmatic. It doe not contain water according to the specs. But I had a bad experience with some other kinds of cutting fluids before that had a similar claim. I use it on the lathe too but the ways are always being wiped & oiled so maybe explains no sign of stains there? Anyone else had issues with the stuff?





						LPS,LPS NATURAL CUTTING FLUID 16 OZ.,1-444-44220,KBC Tools & Machinery
					

LPS,LPS NATURAL CUTTING FLUID 16 OZ.,1-444-44220,KBC Tools & Machinery




					www.kbctools.ca


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## matthewsx (Oct 12, 2020)

Stains on the table are better than skin irritation IMHO. 

I think this is a common problem and although there might be a solution it's probably like dings in your pickup bed, just shows it's being used....

John


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## Larry$ (Oct 12, 2020)

Cast iron is porous so some discoloration is natural. It's way of showing it's not just a wall flower. I recently had the vice off my 16 YO mill. The entire table looks about the same, experienced.


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## Mini Cooper S (Oct 12, 2020)

Some discoloration is inevitable, it is a sign of a working machine.  That said, I always coat the bottom of my vise and the table in the area that I install the vise with oil.  It prevents rust, and I have seen rust form between vise and table even in very humid weather.  I also stone the table with a fine slip stone before I install my vise.  Stone the entire table, not just where the vise goes or the area where the work is done, that prevents a hollow spot from forming over time.

Richard


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## Papa Charlie (Oct 12, 2020)

High sulfur cutting oils can stain the metal surfaces of our lathes and mills. If you leave the vice mounted the sulfur will leach under it and will work through any oils that you may have there to protect the surface.
Best is to find an oil that is very low in sulfur to help.


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## markba633csi (Oct 12, 2020)

WD-40 might help, but I personally hate the smell.  Perhaps some light oil like 3-in-one? I think it's low in sulfur, and I like the smell
-Mark


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## petertha (Oct 12, 2020)

hmmm... I just read the specs for Tapmatic TapMagic. I wonder if thats a generic thing with most all cutting fluids or particular to this one. No mention of sulfur in anything I use.



			https://www.kbctools.ca/customer/docs/skudocs/1-444-10016E_SDS%20Sheet.pdf
		


_· Recommended use: Machining, Cutting, Tapping, and Metal Processing. · Restrictions on use: After use of this product, *clean and lubricate metal surfaces to avoid staining and/or corrosion.* _






						TAP MAGIC,TAP MAGIC EP-XTRA 16OZ.,1-444-10016E,KBC Tools & Machinery
					

TAP MAGIC,TAP MAGIC EP-XTRA 16OZ.,1-444-10016E,KBC Tools & Machinery




					www.kbctools.ca


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## Papa Charlie (Oct 12, 2020)

Tap Magic is Sulfur and Chlorine free


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## Papa Charlie (Oct 12, 2020)

If your cutting oils are free of sulfur and Chlorine, which they appear to be. The stains may be caused by condensation. I see you are in Calgary. Is your shop heated all the time or does it go cold then you turn the heat on when you want to use it. Also, does your concrete floor have a wet feel to it. Cement can leach moisture into the room.

Try cleaning the bed and the vice bottom. Coat boat with a rust inhibiting lubricant and remove the excess. See if this might help. I have a feeling that it is the environment that may be causing the staining which is most likely rust forming in the pores of the cast iron.

A fan running in the shop at all times would certainly help to remove condensation and help to protect you equipment. We live on a boat and it never fails to amaze me how a small fan can remove moisture in the air. They also make those small fan/heaters for boats that work exceptionally well. They draw very little energy and are safe to be left on unattended. Another thought, but pulls more energy is to leave an oil filled room heater running in the room all the time. They are very safe to leave operating and will also circulate air by convection and help reduce humidity.


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## GunsOfNavarone (Oct 12, 2020)

I learned the hard way with some cutting fluids how badly they can stain. After I found this can happen, I read the bottle closer. "Clean area after use to avoid staining. Ugh...$600 Kurt vice... I think it was CRC product...I really liked it too. This didn't answer your question, but at any rate some stuff is just going to do this and I'm curious to hear the answers here.


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## pontiac428 (Oct 12, 2020)

Scotchbrite on a sanding block does well... but if it doesn't remove those gold-colored oil stains, use the blue version of Easy-Off oven cleaner.  Blue is the glycol ether formulation.  If that doesn't do it, use the yellow version- that's sodium hydroxide and you shouldn't use it on metal- unless you are paying attention and have a rags ready.  It works like nothing else on cylinder heads, and turns oil into soap on contact.  That'll strip the stain off.


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## petertha (Oct 15, 2020)

Papa Charlie said:


> If your cutting oils are free of sulfur and Chlorine, which they appear to be. The stains may be caused by condensation. I see you are in Calgary. Is your shop heated all the time or does it go cold then you turn the heat on when you want to use it. Also, does your concrete floor have a wet feel to it. Cement can leach moisture into the room.



Shop has room temp thermostat heat. Calgary is actually pretty dry. My rust issues are practically zero compared to what I hear about in other regions. I am tending to agree its probably the combination of cast iron maybe more open grain that is allowing the oil to penetrate, flash off the light ends & basically color stain. You cant dfel anything & nothing comes off like with a light 1000# stone. Most lightened or came off with WD-40 but like I say its progressing a bit every time I remove the vise. Just a visual thing that OCD eyes are mostly affected by. My Bison vise might be CI but I suspect probably high end stabilized steel. No staining there, even on the underside. Here are some pics I have handy.

Somewhat unrelated, I occasionally will put some card stock between the the moving mill jaw & a part if its not a perfect surface to help bridge micro-nonconformity or if the part is very thin to add some gription. I suspect the answer is No because I've never heard of it, but would it be beneficial to add any kind of paper 'gasket' under a mill vise between the mill table? I'm not actually sure if this would partial seal oil seep or maybe make it worse?


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## Dabbler (Oct 16, 2020)

A paper gasket could 'tip' your vise, especially if it absorbs oil or water based cutting fluid.  You would be better off with copper - except- osmosis will defeat you every time....


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## petertha (Oct 16, 2020)

Good points. I guess I'll just wear sunglasses when I remove the vise LOL.


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