Welding Table Rust

The steel we get from the mills is profiled (grit blasted for paint adhesion) and then coated with (I think) 1 to 2 mils of what we refer to as construction primer. I believe it is a zinc based paint and it is applied to 'hold' the surface prior to fabrication and coatings. An arc can be easily struck through it but it is gaseous and unhealthy when burning like all paints.

If you can do a SP6 blast on the whole rig, it will rust quite quickly and actually doesn't look too bad if it's rusted in conformity throughout. Remember, rust inhibits rust like some bridge girders you see on highway overpasses, or underpasses, depending on which way you're driving.

I wouldn't worry about it. The table is usually used as ground for welding. Any protective coating will isolate the work from ground. As it arcs though it will cause pitting on the work and the table. Better to leave it bare on the top. Just paint the structure. If used enough will not have to worry about rust on the top surface. Dragging the work across it will keep it rust free.

Dear Production Team,

In order to keep the table looking good you need to work faster and do more work.

Sincerely,

Management

-----------------------------------------

I like this. We have always had limited success with the "productivity" angle, maybe this one will work better.

Actually, no coating and keep using it is what I expected. I was just hoping for something I liked better.

Thanks,

Bruce

Having been in management, that would have been my answer too.

" Keep rust off table top by continually moving product across it, repeat daily".

Ozzb had it, I guess admin can shut down the thread now.

"I guess admin can shut down the thread now"

OUCH! Straight to the heart!!!!!!!!!

They better if they don't want us to start talking silly.

Aw come on, its not like the silliness party has won.

They may do a better job then the ones we did elect!!!

Or are the ones we elected in the silly party?

No.....just very seriously pushing through silly ideas.

Paint the surface with high temp stove paint, (it works, I heat with wood and occasionally repaint my wood stove), after that, buy a sheet of 4' x 8' galvanized sheet metal and place on top.

p.s.- If you need more of these in the future, keep your eye out for restaurants going out of business or used restaurant equipment. There are some good deals on big, heavy duty, stainless steel tables.

Galvanized metal gives off harmful gases when its welded or heated up. Not a very good surface for the top of a welding table.

I could be wrong, ( it's happened before), I was visualizing just sparks landing on top, not the surface being brought to high temp. Maybe just a quick wipe down with this would work, http://en.wikipedia.org/wiki/Silicone_oil.

I was trying to avoid "normal oil" in order to avoid the need to clean the welded aluminum with strong solvents prior to finishing. In a past life our shop used vegetable oil based paste/sticks as a cutting lubricant and hot water with Comet type cleansers for cleaning. A safe and legal way to avoid dealing with solvent disposal. I don't know for sure, but some of the silicone oil I was around in the past seemed thin enough that I might be able to wipe it down, leave a protective film and not worry about transfer to the aluminum parts being welded.

Interesting idea.

Thanks,

Bruce

I don't think galvanized sheet is a good idea. Will it not give off toxic fumes if welding is done on it?

Boy kramarat,

We're piling on you today. The problem with a SS work table is that as soon as mild steel is placed on the table it will begin to rust. Remember that "stainless" steel is a misnomer. The proper term is corrosion "resistant" steel. It will still rust in BruceFlorida's environment.

Cheers.

I can take it Just throwing out ideas. Personally, I've never been to a welding shop that gave a crap about ascetics, if it rusts, it rusts. So what?

Hey...I wasn't off topic. I was just wrong.

I don't believe that rust inhibits rust and I don't believe that the table should be painted, or covered. As ozzb pointed out, the table surface needs to be conductive. Sufficient use will keep it in shape.

Bruce, sounds like a nice table.

In my fabrication shop, I can only suggest constant use and even then every now and again the welders have to take a grinder to it to clean it up, (We used large machine bed, as welding table (8' x 20') for construction).

Other than that prime and enamel the support/base and leave it. I won't paint it.......it will atleast look that its being used, otherwise just get a picture of a welding table, and put that in front of it.

p911

I suspect that every penny you saved by building your own table can quickly disappear trying to stop the rust. The simple suggestion I have is to chrome plate the rusting surface(s). Now if this was a funded project, then you might be able to assemble a team of chemists and metallurgists who might be able to find a different electroplated or chemically bonded coating to your table that also conducts. However, even with the most durable coating on your table, this will still rust. I would expect some fair amount of mechanical abuse from hot sparks and impacts to break through any coating. This will always provide rust pitting sites.

So if the metal you used will rust, then live with it or use a different metal.

Sounds like rust is the answer.

It was a funded project. Budget $380. Spent $380. Funding finalized and closed.

What about a light coating of spatter sheild on the rust?

Or Pam for grilling?

I'm hungry.....

I'll experiment with splatter shield.

As detailed in my #33 response to #9, I want to avoid having the rust preventing efforts cause a need to strong solvents to clean up after welding. I might be worrying about nothing here, but oil on the table seems like a problem for our "we don't want to clean the aluminum after TIGging" goal.

Thanks,

Bruce

To keep from contaminating the TIG weldments as well as increasing "down time" for the welding table try a fast drying clear laquer or shellac in a spray can or even brushed from a can followed immediately by a wipedown to leave a minimum film on the surface. Since it will dry fast on the rags disposal should cause no problem. The remining coating residue is a fairly benign organic chemical. Shellac won't work if you like to do cleanup with isopropanol.

To slow down the rust cover the table between shifts and put a low temperature heat source underneath. The idea is to lower the relative humidity of the air by locally heating it. This could be a small 240 volt baseboard convection heater running at 120 volts to put out 25% of the rated wattage in heat. A simple room thermostat mounted on the heater might work. This technique kept a pet iguana happy for 4 years. Make sure that any permanent mountings of the cover pass muster with the fire safety people. They could ask for a sprinkler under it.

Ed Weldon

This is what I used for years. If you buy some good smelling stuff, you'll work faster too, And it keeps the spatters from sticking on the table. Better buy an old bed of a big milling machine. You'll have also T- grooves to attach your workpieces, to keep deformation minimal. GA

Make the top out of gold, it's highly conductive and it will never rust.

#21 is a good idea, but as stated in #15, budget $380, spent $380, budget closed.

I did a little Google work on this one. I don't recall hearing about "Varathane plastic oil". I'm still not sure if this is the "oil based polyurethane" that my browser kept hitting on. The idea of linseed oil or something like it is something I didn't think of. These, and maybe even Tong oil might dry out and provide protection without getting an oil film on the aluminum items being welded. Helpful suggestion.

Thank you,

Bruce

Bruce -- Natural drying oils like tung or linseed are fairly slow to dry. This usually isn't an issue on porous wood surfaces. Alone on your metal plate welding table they may produce the workpiece contamination you are concerned with.

There is an old tech product known as japan drier. You add small amounts to oil paint, varnish, etc. to make the natural drying oil in it polymerize more quickly. You may have to experiment a bit to get the right mix for your application.

Artists who work with traditional oil paints know about this stuff and you may be able to find it in a well equipped artist supply store (not likely Michaels) or one of those branded paint stores that caters to professional house painters and contractors.

An online source is:

http://www.jamestowndistributors.com/userportal/show_product.do?pid=3995

This outfit has other interesting hardware items largely slanted toward boat builders. Good source to know about. Get their catalog.

Ed Weldon

Thank you,

Bruce

I believe it is called Tera bin.

I personally do not think applying any kind of varnish to a welding table top is a very good idea, seems kind of messy and restrictive of an work area. Where as my previously mentioned method allows the table to be used as a work table straight away for other than welding.The oil film is so thin that it does not contaminate anything.Also good welding practice is to have the work lead clamped to the workpiece so the surface does not suffer any arcs and damage.

Use weld tables everyday at work, Caterpillar. Best thing to keep from rusting is a light coat of air tool oil. Not a fire hazard. Sand the top of the table, oil a cloth well and wipe on table as needed. The oil will not interfere with grounding.

If you use it only occasionally, Put a vinyl tablecloth over it when not in use. Don't forget to take it off when you want to weld.

I have used Ospho in the past but had never heard of tannic acid based rust converter products. The people at http://www.theruststore.com/Rust-Converter-Gallon-P40C10.aspx have a product that looks both effective and safe.

Thank you,

Bruce

I believe I said not acid based?? The one in your link is essentially the same.

However I was wrong it is a very weak acid you can pour the concentrated stuff on your skin and it will not burn.Much more preferable to the phosphoric acid types which I would not like spraying around anyway. I also use it on my black steel stock, when it drys I spray the steel with a mixture of floor wax and turpentine so I can store it away without rusting. I can use this steel without having to clean off any sticky preservative coatings. This method is obviously no good for bright steel.

In use as a rust converter i dilute it with water about 40 to1 and it seems to work OK , and it leaves a surface which will absorb pretty much any coating you want to put on it, as in itself if you do not seal the surface with something it will rust again in a very short time.

I have used Ospho type products (phosphoric acid) in the past and they work well.

Thanks,

Bruce

This sounds like a soluble salt item that would require a washing with a soluble salt remover to remove non-visible salts that are on the ionic level. You can learn more at the impartial paintsquare.com website that is SSPC related. Perhaps the key here is that for approximately a dime per sq ft, you can clean the surface and then if desired put any top coat you wish on the surface. Airborne contaminants are carried around and the natural corrosion cell is completed when the electrolyte exists. The salts to make the electrolyte unique in conjunction with humidity and air are the ingredients for corrosion.

Thank you,

Bruce

May I suggest treating the rusted steel plate with a product called "Evap-O-Rust"? You can buy this product at Lowes, Tractor Supply or directly from the manufacturer's online site for around $20. I've used this product and other products (both of the liquid rust dissolver for around $20 and the rust remover Gel formulation for $50) bought from "The Eastman Company" with great success, and I arc weld on top of the treated plates. All 3 products do come in 1 Gallon plastic jugs. With Eastman's Gel stuff you just brush on a coating and then cover with plastic wrap and let the goop just work it's magic overnight. Truly amazing stuff and very safe to use. You should see the results performed on my old rusty tools, let alone pieces of structural steel shapes and plates, bolts, washers and nuts that were once coated with thick corrosion!!!!

Products remove corrosion from the steel that's in an immersion bath, and provide a protective coating......but you must drain the fluid (can reuse until "spent") prior to washing the steel with plain old tap water. BTW, this stuff is so high tech and cutting edge that all US military services as well as NASA use them for rust control!

Products are environmentally safe and have no VOC's.....check out the MSDS info!

http://www.evaporust.com

http://www.eastman.com

Please check out all of the available information regarding these two products! I highly recommend them....

Have a great Labor Day Weekend folks!

Signed, CaptMoosie, LPE/PhD

Thank you,

Bruce

remove all traces of rust, wash thoroughly with acetone or alchohol to remove any traces of oil, spray it down with Selenious acid. this will turn the table dark blue/black. rinse the acid off and then spray it down with light oil.

you've just blued the table just like your gun is blued.

It looks like great stuff. I wonder if the following quote from Wikipedia might be a bit of an acceptance problem:

"... selenous acid is highly toxic, and ingestion of any significant quantity of selenous acid is usually fatal. Symptoms of selenium poisoning can occur several hours after exposure, and may include stupor, nausea, severe hypotension and death".

Still, it is something I want to remember. I have seen copper and brass treated with it, I just didn't know what the chemical was. I'll keep this one stored in my memory banks.

Thanks,

Bruce

Birchwood-Casey sells it in small quantities for gunsmithing, dunno if they sell it in say gallon quantities or not but since it is used to patina bronze, I'm sure art supply stores probably can get it for you.. Selenium Sulfide is the active ingredient in "selsun blue" shampoo. perhaps neutralizing it with powdered sulfur from the garden store before rinsing would alleviate any toxic concerns.

I've used in numerous times (in small quantities) touching up worn bluing or machining marks from gunsmithing without problems.

I have never seen a welding table with a flat top. They are always made from a grate, so that the sparks and stuff can fall right through, and so the oxy cutters don't damage anything. Whenever I have a small piece of metal which could fall through the grate, I just slap a piece of 16 gauge up there, and weld on that, and try not to weld the workpiece to the temporary top.

There may be ways to prevent rust from forming...wipe down with light oil daily would be a good thing....I wipe down all the machinery every day with WD-40 or air tool oil. The drill chucks and lathe beds seem to like it. Its part of the clean up. Chemicals such as LPS2 or WD-40 have two parts to them...one part carries the oil, and flashes off right away, the second part is the oil. There won't be enough oil on the table to cause a fire hazard...but your oily rags now....keep them under control.

Yusef1 -- A flat top welding table comes in handy when you need to weld an assembly to fairly tight tolerances clamping down every piece in your setup. In it's previous life as an assembly fixture mine got a 6" hole in the middle and a number of threaded 1/2-13 through holes. These are handy for clamp locations away from the table edges. I use a cheap Chinese 1/2" clamp kit, the kind you use on a milling machine, with the threaded holes. The other nice thing about my table is that its 4 edges are machined "square" within about .030. So any single corner acts as it's own reference for aligning two parts at 90 degrees.

I have an old drain grating I use for oxyacetylene cutting. But that's rare for me. The cost of acetylene is a whole lot more than bandsaw blades and the latter do a much nicer job. And then for the big and intricate stuff there's a waterjet shop out in Las Vegas that gives pretty good prices to us Landspeed racers (or probably anyone else these days given the state of the economy).

RE: oily rags. I've never observed a any kind of warming of the kind that may result in spontaneous combustion in oily rags when the oil is a blended lubricating oil like motor oil or machine lubricants in 50 plus years of getting my hands dirty with the stuff. I think that hazard is way overblown. But I have on occasion started small fires in such rags from welding, cutting or grinding sparks.

But drying oils such as associated with paints and similar finishes are another story entirely. That Varathane plastic oil I mentioned is such a case. Any rag or Bounty towel saturated with that stuff goes outside to dry on a metal surface one layer thick for a day or so. Old slightly rusted baking tins, the kind you find at flea markets for a dime or a quarter, are great for that.

Another thought on that subject (getting a bit OT here) is that I've largely switched over to using the Bounty towels in my shop. They don't stay around long and accumulate to where they become hazardous. I have a whole bag of clean rags that I almost never use except that I usually keep a couple of grimy slightly oily ones around to use as dust/rough clean rags because they pick up dirt better than the Bounty towels.

Ed Weldon

Guess it depends on what you are going to weld.

The grates I have seen (and have in MY shop) are made from angle irons welded up together, with the fins sticking up. Because welding swarf falls down between the fins, the top edges stay pretty mechanically accurate, and stay in the correct plane, whereas if I tack a temporary table on top of the grate, bits of swarf and garbage get under the workpiece and cause it to rock and twist, and not line up. Plus the fins provide a good place to ground the workpiece. Just MY experience. Maybe if I get pieces heavier than a a door panel to weld, I might invest in a nice flat table.

Another thing about using a grate as a welding table...don't have to clean dust off it. Or employee coffee cups.

Anyway, this comment is not helping the OP any, just 'splaining why I do it the way I do it. I have to admit that there are always several ways to skin a cat.

Regards

Yusef

that all depends on what your using it for.....i used a 96 x 240 machine bed that came off a giddings and lewis mill. Worked great for assemble large machine had a flat stable platform to build off of with tee slot to have clamps to fasten down the machine we were fabricating. Plus occasional we have to weld a jig onto the bed for a jig which when we were through we'd grind off. Each fabricator had a table made with a 48" x 120" x 1" cs plate. Each shop is different.

Never thought of welding jigs to the table. Always just clamped them to the fins....

I will HAVE to use these suggestions!

Wait just a minute...I think I've come up with a way to kill two birds with one stone.

Paint the welding table with nice tropical colors that mesh with your home decor.

Take it home and put your TV on it.

why not copper or tin plate the surface. Gas welding rod is almost always copper plated to keep it from getting rusted. when I was a kid we used to copper plate iron and steel by using copper sulfate solution and a battery. Perhaps you could come up with something like a paint brush with the solution hooked to a battery charger. in the past I used a paste for printed circuit boards that when rubbed on the metal parts, would plate out a tin coating by galvanic action. I'm sorry but I cannot recall the brand name of that paste, perhaps other contributors could help us out there.

To keep on touching up a workshop table is a lot of unneccessary work, and you will have hassles with weld ground. You will, hopefully, regularly clean the table. As a final wipe you use a rag wetted with old oil (From those trucks?) It is safe and rustfree. You dont drop liters of oil on the table, just enough to "colour" the surface. It wont rust and it wont prevent grounding either, but it will look good.

I totally agree with jvri, it seems the most cost efficient & practical solution. I would do the same. Considering the use of 'electrodes' to prevent corrosion on ships, can this not be somehow applied to Bruce's application?

Your welding table will remain rusted all the time for it is used for electrical connectivity by fixing earth cable to it and the work is being welded by placing on the top of the table. You can not avoid it. If you use any coating, when coating become thin by usage, electrical spark would make more damage than the rust. Keep clean the table with power brush and you will use it without damage.

As the previous post stated, a sacrificial anode made from zinc, aluminum or magnesium should provide the corrosion protection, when the table isn't being used.

http://en.wikipedia.org/wiki/Weathering_steel

not all steels weather the same

I recently did this http://www.refurbishforfun.blogspot.com/ and built a rusty bike (I rode in to work on it today).

If you have used any stainless fastenings anywhere on your table this will accelerate the process.

A large fan blowing across the table may slow down rusting by keeping moisture from settling on the top. Remember, when warm-moist air hits a cold surface, moisture condenses on the cold surface. My shop is in a humid location and the only time I have problems with rust is in the winter time when machines get cold at night and warm-moist air hits it during the day. During the warm months, the temperature stays constant enough that condensation isn't a problem.

We get a lot of hot air. Sometimes the hot air is from the Florida sun, sometimes it is from ... well, that would be going off topic.

Bruce,

One plant I worked in, allowed the guys to manufacture their own work tables, so some had shelf space underneath that made cozy sleeping arraignments (aside from occasional "wake-ups" from the noise produced by a 5 lb. compo-thane hammer). I noticed these tables did not rust. Perhaps it is due to the old adage "Rust never sleeps"?

We may be in luck. It would seem that our staff is very skilled at rust prevention.