Construction cleaning question

[samuel taylor]

Hi everyone.

haven't posted for a long time on here but I have a construction cleaning question.

I run a manage a construction cleaning company 50+ cleaners and we keep getting this problems with exposed Duckwork. The guys installing them are leaving hand prints All over the Galvanised Ducting.

We have tried wd40, galvanised cleaner, degreaser, polish.. etc.

Has anyone got any ideas to get the handprints off?

Sam

 

[Stephen courtney]

Hi Samuel,

Have you tried a steam cleaner on it?

Ever since I started using them in my company it's been a game changer, they get a lot of things clean that chemicals struggle with.

I would say now though that it might take a few steams to break through the chemicals you've used before you get to the actual print.

I'd buy one and give it a try if you don't have one already. If it doesn't work you at least have a handy tool for other stubborn jobsm

Kind regards,

Ste

 

[Jamie Biles]

Hi everyone.

haven't posted for a long time on here but I have a construction cleaning question.

I run a manage a construction cleaning company 50+ cleaners and we keep getting this problems with exposed Duckwork. The guys installing them are leaving hand prints All over the Galvanised Ducting.

We have tried wd40, galvanised cleaner, degreaser, polish.. etc.

Has anyone got any ideas to get the handprints off?

Sam View attachment 31301 View attachment 31302

Have you asked the installers what it's likely to be. Must be a product they use on their gloves that's being transferred. Anything else would have come off by now using your mentioned cleaning I would of thought.

 

[samuel taylor]

We have had conversations with trades this is caused by them installing it with out gloves and handling it with dirty hands. We have screamed this for years wear gloves or leave the protective plastic on.

ive sent a email to manufacture to see what they say but I can imagine it will be helpful.

the only problem with the steamer is that units have electric to them and are about 8k a peace. I’m scared of damaging the unit if i used a steamer

 

[Mark Roberts]

It's called white rust

Have you tried wiping it with an acidic rinse

 

[Jamie Biles]

I'd wait for manufacture response. Or even better,ring them and have chat. As mark said,be inclined go mild acidic. White vinegar maybe in small area test.

 

[Jacob Ward]

The zink dipped metal has come Into contact with oxygen or water ,

The galv is either incorrectly done allowing oxides to form.

I think you wont be able to stop it

Especially since it's being used for hvac as it is being exposed to condensation from the cold or hot temps of the system.

J

 

[samuel taylor]

the job is a refit so all the hvac stuff are brand new.

everything I’m using is taking the zinc off so I believe this may have been done during manufacture. 20 of my Clothes and now black.

the marks look identical to a hand prints if Forensics kit I could identify who do it. How can oxidation create Hand mark shape.

can grease on you hand stain the metal?

white rust this is a new to myscould you explain a bit more. A google search wasn’t much help.

 

[Mark Roberts]

Most likely it's hand marks yes. In college it was quite amusing doing sheet metal work, you could tell who had the sweaty hands as the next week their work would be covered in rusty hand marks. In galvanised metal it appears like your pictures, darker.

Somebody has very sweaty hands, its salts and other chems in perspiration which causes the white rust

If you want to definitely get rid of it, fine wire wool the whole thing, I wouldn't get involved personally as you could make it worse

 

[samuel taylor]

Hi mark, Theses sites can get very warm when you have 50 guys and no airflow. is there a way you were able to clean those marks off?

 

[Mark Roberts]

I'd explain it's corrosion and not really a cleaning job first. If they want you to have a go, get a disclaimer. As above, mild acidic solution or wire wool, both carry risks and you could remove the coating

One of the reasons cats & dogs like licking your skin so much is because you taste like a salty bag of crisps to them

 

[samuel taylor]

Hi mark,

Thanks you to everyone who comment on my question.

we get it all the time, trades think’s everything just wipes off.

we Tried may ways used the white vinegar as commented above, we tried milk as google search mentioned but all it does is take off the zinc coating ( they had a spare ducting we used as a test Peace) even used metal polish but just made it shiny but still kinda see the marks

so I’m primed for my talk with the pm…

the salt from the trades sweat has reacted with the zinc coating to course a corrosion a form of white rust?

 

[Mark Roberts]

I would say it was done early in manufacturing or packaging, but someone's had there sweatys on it for sure

Its sweat contamination, sweat contains all sorts of toxins that can react to metals, zincs etc

Had a quick look around and found this thread with a few more pictures, sometimes it shows as white powder or dark patches https://www.finishing.com/182/13.shtml

Certain people have very sweaty hands, in our class it only happened to a couple of the lads, but the same lads every time