Obviously if penetration is low the effect is much less.

With coated steel, just grind back to bare metal anywhere that needs welded otherwise it will splatter like mad.

 

Most mandrel bent tube has bend lube residue in it. That lube is usually water soluble, and will wash out. I use Purple Stuff and pull the rags thru w/ a wire.
All my turbo welds are tigged/purged. [304SS]. Outer sides are scrubbed w/ Acetone and Scotchbrite.

 

Sorry to thread jack a bit but while on the topic of welding prep, is mineral spirits a suitable cleaner for weld prep?

 

I use urethane paint reducer because i always have some laying around from all the paintwork i do. That **** degreases ANYTHING. lol

 

U do realize that the sugar is not exactly penetration. What itis is carbon which is not good with stainless can cause welds to be weak. With the proper fitment and good a weld u wont have burn threw / carbon/ sugar or whatever u want to call it unless u decided to weld it at 100 amps which is over kill. I weld food grade stainless equipment all day everyday we have any sugar part is junk... I also worked at ams performance welding all the stainless parts for gtr s...

 

You can use the aluminzied steel. Just be sure to have a fan blowing the dust away from you and wear a mask. All the
coatings like zinc galvanized and aluminized all give off toxic fumes when welding but when grinding the dust particles are just as bad.

Don't be afraid to weld your own projects. You will never learn unless you try it out yourself

 

Sugaring is normally from the chromium in stainless. Carbon steels without it don't require a back purge.

With stainless back purging is pretty much required otherwise you risk a VERY weak weld.

 

Back to the question at hand, are there any tool like wire brushes or pipe cleaners that will get into the pipes to clean slag off?
Maybe a drain cleaning wire wheel drill attachment?

 

I only TIG. If you want a full penetration weld use backing gas. Sugaring a weld is just asking for pin holes. I use a die grinder with a 120 or 150 grit flap wheel if you want to make it sanitary and look like the weld was never there.

 

Just saw this and wanted to elaborate on the hazards of some aspects welding if its ok since its part of my job. Just be extra careful when cleaning off or degreasing the material to be welded with Chloronated Hydrocarbon Solvents the end result is the creation of Phosgene gas and at times Hydrogen Chloride (HCL) due to the UV radiation created by most welding.

Also, welding aluminized steel can create respiratory irritation.

Just be sure to weld in a well ventilated area and/or use some type of exhaust system that will move the fumes and gases away from your breathing zone.

Good info here btw...thanx.