Cleaning before welding

[cspcrx]

Picked up 100 feet of steel tube for my workbench build. I noticed that there is oil on a lot of the steel. Not sure if this is there to protect or keep it from rusting but I know I will need to clean it prior to welding things up and painting.

Tips on the easies way to do this? Thinner, brake cleaner, etc and shop towels?

Thanks all, showing how novice I am.

 

[brownbagg]

noooooo brake cleaner, that and welding creates a poison gas. kill you dead

 

[BryceW]

You can use brake cleaner as long as you use chlorine free break cleaner. Because I weld and do automotive work I need it for both and only keep chlorine free in the shop to avoid any nasty surprises. It is however an expensive way to prep metal. I use it for things that are odd shaped and difficult to clean, usually on old machinery. For plain old steel tubing just grab some acetone and a rag.

 

[Zephyr20]

Acetone or lacquer thinner and a rag

 

[Bodj Built]

Yup, for all my metals I use acetone. Run over to your local big box store and they usually have a gallon or so of it for around $15-17. Also, use paper towels so you can just toss them after.

 

[Bigblue&Goldie]

+1 for Acetone. As mentioned, get the big gallon jug and some good, thick paper towels/shop rags. Brake cleaner leaves a residue that I don't like.

 

[Craftfab]

Due to how toxic Acetone is when absorbed in your skin (always wear proper gloves with it), some use denatured alcohol as well. I have both on hand.

"Hot Rolled P&O as it is often called, is Carbon steel that has had the 'scale', that typically coats the steel after being formed, removed through the process of an acid bath. In order to prevent surface rust from forming after the process, the hot rolled steel is coated in an oil. The process of the acid bath is the 'pickling'." - from Arlo's website.

 

[cspcrx]

Thank you guys. I have some Acetone, rags, and gloves that I will use to clean before I prep the metal for welding. I plan on flap disking the areas where I plan on welding to get to clean steal to ensure cleaner welds.

I appreciate the help in pointing me in the safest direction.

 

[LXCam]

Another vote for acetone and rags. But what I do after everything is cleaned off is burn the rags.

 

[lilredex]

When you weld it up, put your ends on flanges, so it can be taken apart for moving. Somebody will thank you down the road.

Hard to see in my picture, but that jack is pushing up on my flanged cross member behind that plywood tool board front.

 

[danielbuck]

the oil/coating is normal, this protects the metal from rusting from the factory.

I usually wipe off the tubing with paper towels to get the bulk of it off, if you have gojo rags they work great as they have a grease remover saturated in them. or any type of degreaser (Simple Green, LA's Totally Awesome, or what not)

Then acetone/alcohol/whatever where I'm going to be welding.

If it's something I don't need to be perfect, I'll just use gojo rags and nothing else. Alot of jigs and fixtures I never end up painting, so if there's still a bit of oil on there I don't care.

I usually don't put acetone on the entire piece of metal before welding if it's long lengths of tube, as I'll generally do that after the piece is done welding and getting ready for paint. And at least in my work area, the tubing will get dirty again from general handling and what not, so I don't bother cleaning the entire length of tubing with acetone off the bat. At first I just acetone the ends of the tube and anywhere else I'll be welding. And then the entire piece with acetone right before painting.

 

[sberry]

I have even cut, fab, clean, tape ends and prime pieces before welding.

 

[Slackerzinc]

I really only worry about cleaning the oil off the steel if I am Tig welding it, stick and mig I just lightly wipe it down with a rag to remove the bulk of it.

 

[cspcrx]

Thanks. I figure it needs to come off in order to paint it but I see the point you guys are making about while building it. Going to have to clean it again after handing it. I guess I wont let my OCD take over on the cleaning then.

 

[NUTTSGT]

Acetone or lacquer thinner and a rag

This is what I do, along with using a roloc disc to clean the mill scale off.

 

[LXCam]

Thanks. I figure it needs to come off in order to paint it but I see the point you guys are making about while building it. Going to have to clean it again after handing it. I guess I wont let my OCD take over on the cleaning then.

Couple reasons what I thoroughly clean it right off the bat. It's butter smooth without anything to catch and tear the rags plus you can hit every square inch easily. The other is with all the handling you'll get that fricking **** all over everything including areas you just prepped to weld. Your results may vary but I'd rather clean off some lite surface rust after the fact then the latter.

 

[Bigblue&Goldie]

I typically will wipe down all my material with acetone right before I start a project to keep everything from being covered in oil and attracting metal shavings and dirt. In AZ we don't have rust problems, so it's not an issue to remove the oil. If it's an item that is being powdercoated I don't worry about light flash rust as it will be blasted off. If the item isn't being painted /coated, I wipe it down with a heavy layer of WD40.

 

[tarmy]

I have been using this for years...


Here in Commiefornia...they keep making all the cleaners weaker by the year...

 

[sberry]

My benches are nothing to write home about in the terms of fancy design and custom workmanship. But, they work well enough that there is not much incentive to replace them. Like a lot of it much of it was found and added or adapted.
Your climate is good but a lot of this can even be left bare or semi bare, sometimes I simply paint flats I can see, doesnt all have to be a show car, doesnt need to look like scrap but inside corners no one can see may not be a big deal.

 

[danielbuck]

Thanks. I figure it needs to come off in order to paint it but I see the point you guys are making about while building it. Going to have to clean it again after handing it. I guess I wont let my OCD take over on the cleaning then.

I used to clean extra good all the time before welding and building, but over time you get lazy (er... efficient) and only clean when and where you really need to. If I'm MIG welding something unimportant, alot of times I won't clean at all, just wipe off. After a few projects you'll figure out what works best for you. Sometimes you just have to deal with what you have, like when welding under a vehicle, you can't always get it very clean.

Same thing with mill scale. If it's important, I'll grind it off where I'm welding. You CAN weld through it. I don't know if you'll get a real pure weld though.

If I'm TIG welding, I take it down to bare metal and usually wipe with acetone. I **** at TIG welding, so I like to give myself every advantage to do it good.

 

[sberry]

I grind rust on Mig. I do most any time I can. Often pick new steel off the shelf when there is a lots of weld, or even minor on small pieces.
Stuff over various scale. I was looking for a couple that could show good cleaning after the weld and see the scale along side but not sure I got it here. OK, last pic. 3 is also over a new mill scale plate, 4 is over a dirty rusted used plate no clean, 1 pass up on old trailer.

 

[cspcrx]

I appreciate you all sharing your experience. This will be my largest metal project yet, 100ft of steel, so trying to avoid waist and stumbling points.

Love this forum, so much knowledge and so many willing to share.

 

[dogdog]

my prefer go to is the prep-all , drys relative fast, and not as stronger smell as thinner or acetone etc...

http://www.kleanstrip.com/product/prep-all

but if it is hiding from me, then acetone, thinner etc... sometimes even tsp dependents who is hiding from me.