its not rust ?

[paul-uk 500]

did a drive the other day and had what i thought was a rust stain...used oxyalic on it and nothing....i have read it might be antifreeze which can leave a simalar stain..any suggestions...

[John Orr 206]

Paul,

There are a few possible sources for these stains: Rusty antifreeze, water dripping off a rusted automobile and muriatic acid. Occaisionally, Using a stronger oxalic solution will work on the car rust, but I have no solution for the others. I advise customers with these stains that they may not come completly clean.

By the way, I know that muriatic acid will cause these marks from personal experience. lol

[Aplus 525]

If a stronger solution of oxalic doesn't do it, the stains may not ever come out. When dealing with rust, I tell customers in advance that the possibility exists that I won't be able to completely remove the stain.

[paul-uk 500]

thanks for the reply......john i remember the muriatic thread it was'nt funny at the time lol........tony i did tell him it might be a prob.......thing is he is a chemist..he gave me a tank and has also some chems to try on a house wash so i did his drive(20ft) for him...you never know he might try to come up with something for it.

cheers paul.

[timhays 14]

i think oxalic is used primarily for a non ferrous rust stain,and a phosphuric and sulfuric acid solution is used for the ferrous rust stain you are referring to.

[paul-uk 500]

thanks tim sounds about right...i dont use either acids but will see if i can pick some up.

cheers paul.

[Russ Johnson 141]

I'll bet that hydrofluoric will get it. Just be careful.

[Aplus 525]

Paul, If your chemist/customer provides something that works, please let us know.

[paul-uk 500]

will do...but he is the typical scatty scientist kida guy.....mad busy right now but will run a few things past him next time i am passing his place....

[chirobob 14]

Paul, I woud stick to the Phosphoric Acid, I have never used it combined with Sulphuric though. I buy the Phosphoric at 85% and dilute it down to 40% this is inline with most of the commercial rust convertors(you can also add a surfactant with it. I am going to be doing an access road at a steel mill on Tuesday 13th with rust on the concrete 500m square, so I'll take some pics and post them on the board. I tried using oxallic on rust ages ago and didn't get results even close to the phosphoric effect.

Cheers

Jason

[paul-uk 500]

thanks jason..i look foreward to seeing them.......i'll pass on mixing those two chems for those that know what they are doing..also there is no money in this job for me to take a chance playing with chemicals.....but i have a few options now from these posts for future ref.

cheers paul.

[chirobob 14]

thanks jason..i look foreward to seeing them.......i'll pass on mixing those two chems for those that know what they are doing..also there is no money in this job for me to take a chance playing with chemicals.....but i have a few options now from these posts for future ref.

cheers paul.

Paul,

here you go I tried to post the complete series of these on the board, but had problems posting them, so they are on a couple of the other boards under Rust Removal.

[paul-uk 500]

hi jason,

i have seen all the pics you posted on this and i thought you did a great job, and like you said if you could post the pics without any loss of quality(i think it was 8 mill pixells)it would actualy show how good a job it ended up....i think tim hit it on the head and it was a non ferrous stain and as i do not use those particular chems it will have to wait as it was academic as the guy was a chemist and was not bothered about it(bigger fish to fry) no need for me to go all in on this one..i will wait till i come across some of the chems tim mentioned.......by the way try and post your pics here as some guys dont go to the other boards and will of missed them and it was good to see the finished job.

cheers paul.