One Tough Pressure 580 Report post Posted May 8, 2003 I have read many posts on this, and have tried it a few times, with no luck. After reading more about it, I now believe that I was not allowing enough dwell time. I mixed it at 8oz per gallon of water as most say to do and applied with a pump up sprayer. In my frenzy to roll up and go home, I may have caused the bad performance myself. How long should it dwell on concrete for brightening? I have seen one Company say to spray it on the driveway while cleaning the back of the house and when you come back to the front, it will have done it's job. Seem's as though it would dry in that time.Does it need to stay wet? Share this post Link to post Share on other sites
ron p 500 Report post Posted May 8, 2003 why are you rinsing it at all? Share this post Link to post Share on other sites
One Tough Pressure 580 Report post Posted May 8, 2003 Don't know, guess that I thought you should. Is that the problem? So then I should wash as normal, and then apply the Oxalic? Would it need to be mixed stronger since the surface is still wet from washing? Share this post Link to post Share on other sites
ron p 500 Report post Posted May 8, 2003 OTP if your just washing with hot water and no chem. You wont see much brightining effect. Unless iron deposites were present. Share this post Link to post Share on other sites
One Tough Pressure 580 Report post Posted May 8, 2003 It depends on the job, if I can get away with hot water only or if I need any chems. Are you saying that Oxalci needs chems to do the brightening? If so what? Do you use Oxalic for Concrete and if so what is your process? Share this post Link to post Share on other sites
paul-uk 500 Report post Posted May 18, 2003 i would like you to elaborate on otp's last question if you would'nt mind :confused: cheers paul. Share this post Link to post Share on other sites
One Tough Pressure 580 Report post Posted May 18, 2003 I have been waiting patiently for that reply... Share this post Link to post Share on other sites
paul-uk 500 Report post Posted May 19, 2003 you see he is not snowed in now and he's got a helper aswell....not enough hours in the day now :)......if we keep it bubling on the top he will get to it..... Share this post Link to post Share on other sites
ron p 500 Report post Posted May 20, 2003 I feel that the oxalic acd only work's when iron deposites are the problem or you use a caustic detergent first. It's like 2 stepping. White ox sell's cement brightner and oxalic is the main chem. Also the type of sand used in the cement mix can make a diffrence. If they use the brown sand, it wont brighten much. I dont rinse the acid. Sorry it took so long. Share this post Link to post Share on other sites
One Tough Pressure 580 Report post Posted May 20, 2003 Maybe I got the brown mix, will have to try again. Share this post Link to post Share on other sites
paul-uk 500 Report post Posted May 26, 2003 we only use brown\red over here Share this post Link to post Share on other sites