How to remove limestone stains from brown plastic

[RobH]

Recently, I redesigned part of my garden and put in a circular self binding gravel path. Anyway, now with the heavy rain / downpours, the top surface of the path looks like it has been picked at. I did use a whacker plate machine to compact it. Also, when it has rained heavily, there are limestone splash marks on the brown plastic edging I used between the path and soil.

I have tried : turps / white spirit,weak mix of bleach in water, and a proprietry stain remover, albeit for fabric. I have also used just a wet / damp rag, but no matter what I have tried when the edging dries out, the stains are still there.

I googled my problem but all I got was limescale remover. Is limescale the same as limestone stains, I didn't think so

[Chris Hogg]

What colour is this staining? A picture would be helpful for diagnosis, but you can't post directly to this newsgroup - you have to upload it to an image-hosting site. Not quite sure what you mean by limestone stains. Limestone is calcium carbonate, same as chalk, and yes, it's the same as lime scale. Limestone is only very slightly soluble in water, so I doubt if of itself it can cause staining. Fresh cement will sometimes 'bleed' white deposits, but these eventually dissolve away. If you still think it's caused by limestone, try cleaning it off with dilute acetic acid such as vinegar, citric acid such as lemon juice, or in the extreme try brick acid.

[RobH]

The colour of the staining is like a yellow to cream colour.

i said limestone because , well, I thought that was what self binding gravel was, doh! In fact it's actually called Geo Selfbinding Gravel, which I bought from a localish supplier. Whether that's limestone or not, I don't know, but from the information on here:

It says it is premium quality angular limestone.

Thanks

[Chris Bacon]

It would be odd were it anything but limestone residue, unless there's something else in the self-amalgamating, but as Mr Hogg says, try brick acif. You can get 5L very reasonably from Toolstation (Bostik I think, hang on... yes, "Bostik Concentrated Mortar & Brick Cleaner 5L" £6.15 (you can get it cheaper "Feb" or whatever elsewhere)). You'll also want a brush or rag and rubber gloves. Do a small bit first to check it's OK, the stuff's hydrochloric acid with additives.

If it doesn't work, you've enough really, really efficient lavatory descaler for quite a while, you only need about 50ml at a time.

[RobH]

The problem is that every time we have a solid downpour, like we have had this month, it hits the compacted surface of gravel that hard , it seems to splash something up to the brown plastic edging I put in at the time. It seemed like a good idea when I put in the gravel path, but it's not looking like that when we have a downpour. If I clean the edging once, I bet I'll be doing after every downpour :)

I'll try some brick acid, and or maybe some limescale remover.

Thanks

[Chris Hogg]

Our old friend 'the paving expert' has some useful information on self-binding gravels.

Basically they're just gravels with a lot of fines and dust in them, that helps consolidate the coarser stuff and bind it together. It sounds like what you're getting is splash-up of the fines in the surface onto the edging, where it tends to stick, possibly because that edging is fresh and susceptible to things adhering to it. I expect that that susceptibility will change as time goes on. Meanwhile, brick acid, but wear Marigolds and some sort of face shield, as it's not the sort of stuff you want to splash all over yourself.

[Paul]

That stuff is not a toy.

Paul

[The Natural Philosopher]

Mostly it is: calcium carbonate

[The Natural Philosopher]

It's less damaging on skin than it is on jeans..

[RobH]

Ok thanks, but every time it rains and comes down like stair rods, it splashes it up and doesn't seem to want to come off that easily.

It kind of make me wish I'd used ordanairy gravel now, aargh!

[Chris Bacon]

Suggestion: Add a layer of pea gravel to prevent splashes. Note that if you use 10mm it may "walk" on the soles of people's shoes (but so does self-amalgamating...), if you use 20mm it won't, but does not look so nice.

[RobH]

Thanks for that tip. I have about a 3/4 bag of 10mm pea gravel, which I'll try as an experiment first. Then take it from there.

[The Natural Philosopher]

In time the dusty stuff will wash down and the gravel will be left And the grass will grow...

[Brian Gaff (Sofa]

Its probably so soft its scratched and now looks rustic, in a couple of years it will be cracked with heat and cold and looking completely naff. I'd never use plastic edging again. I tried some white upvc stuff some years ago when I could still see a bit to have a line to follow, but it soon went grey, yellow or brown and then brittle and cracked. Also it was extremely easy to damage by lawn mowers and strimmers.

Brian

[Andrew]

That'll dissolve the limestone path nicely :-)

[Chris Hogg]

In which case, problem solved! :-)