Weiss ft plus on the dreaded black limestone - Second coat advice needed

[eyebrows]

Hi all
When the weather gets better (a lot better) I'm going to be using weiss ft plus on my black limestone slabs.

When I ordered it I was told I would defiantly not need 2 coats, and was advised if I was going to I had to apply the second coat almost straight away.

But reading the advice on Colour Restoration from, http://www.pavingexpert.com/stonpv05.htm it indicates that the first coat was aloud to dry for a couple of hours.

So i'm a bit confused about what to do when it comes to adding the second coat?

Any advice would be gratefully received

[RAPressureWashing]

I have not used the FT but when we have sealed Limestone, we have nearly always done two coats, allowing the first coat to be touch dry first. Hopefully you are not thinking of sealing at the moment as IMO temperatures are to low at this time of year.

[Tony McC]

Without rummaging through my chaotic library and relying solely on memory, I think you are supposed to allow it to become touch-dry, as Roger says, but because I was treating several pavers with a multiplicity of products, it probably was a couple of hours between coats on that trial.

I can't see the logic of of a one-coat-straight-after-t'other approach. You can only apply so much of the sealant without it beading or pooling on the surface. Black limestone is not the hardest or least porous of the limestones, but it isn't anywhere near as thirsty as, say, Mint sandstone, so it takes time for that first coat to penetrate and/or partially dry before the stone is capable of taking any more.

Who told you two coats? Was it someone at SteinTec or another source?

[eyebrows]

I've got no intention of doing it yet, just getting ready for some very dry weather!

I took the steintec info to work and ordered it through my work (jewson's) I'm not sure if that was our supplier though as i don't work in the office.
I did speak to our supplier on the phone to ask about the second coat, i'm sure the guy said they had a trade website i could order through to get the same discount as my work but i can't remember the name of it, tough trade or something like that, i will get them to dig the invoice out at work tomorrow and let you know

They basically said within 20min which confused me. How do i walk on it to apply the second coat when its still wet!

What i was thinking was a coat first thing in the morning then the second coat mid afternoon, on a summers day?

Not sure about the question you ask "who told me 2 coats? " Thats what was used in the trial. The supplier told me i only needed 1 but i would prefer 2?

[Tony McC]

Sorry, I didn't mean to question the use of two coats, but the timing between the two coats.

I'll see if I can get the man behind the company behind Weiss to post a definitive answer for you....

[eyebrows]

I checked the invoices at work today, it was steintec that advised me,

They said only 1 coat but if I insist on 2 then the second should be straight away

[Tony McC]

Here's the reply I had earlier today - not sure why he doesn't want to post it himself!


Hi Tony

Sorry if there's been any confusion over this. The fact is, none of the opinions expressed are wrong and none can cause problems.

Timing is not crucial within the normal span of a normal working day. FT Plus does not dry and set up so very quickly, although "next day" might be problematic. However, we don't want customers to waste material or achieve a less than perfect result. For this reason, if we are giving individual advice, we ask questions and listen to the answers, on which basis we might suggest that for a specific project one or another procedure will be most straightforward and also give the best result. Not every stone is the same and not every site is the same.

It is desirable for as much FT Plus to soak into the stone as possible but we don't want an excessive amount of product to dry on the surface, wasting money. We'd rather the customer got good value.

A black limestone is not a very "thirsty" surface and an excess allowed to sit on the surface for a long time might start to skin. Little and often might be a better approach for such a surface.
With a more porous stone a more relaxed approach might be more productive and easier to manage, allowing some time for the first coat to soak in before applying a second.

In some situations, one coat might be sufficient. If the stone really drinks the product, a second coat and even another might be beneficial. The more we can put into the stone, the better, but we don't want to waste money by allowing it to skin and dry to a hard glaze on the surface.

I hope this makes sense and is helpful.

Regards.

SteinTec, 730 London Road, West Thurrock, Essex, RM20 3NL
phone 01708-860-049
fax 01708-860-893
mobile 07774-173-834
mobile DE +49-1573-4049-309
website: www.steintec.co.uk
eComm: www.tufftrade.com

[lutonlagerlout]

looks a pretty honest answer to me
LLL

[London Stone Paving]

Can't argue with the logic. We do presealing a little bit differently. We apply 1 coat, let it go for approximate 20 minutes, apply another coat and this time wipe off any excess and let dry for 24 hours (in dry weather though it would not need 24 hours). This is how we have been advised to do it by dry treat and they offer us a 15 year guarantee.

[Tony McC]

...but does Dry Treat preserve the colour of black limestone?

I didn't give it a full testing in the trials because it had no effect on the already-faded samples and someone who shall remain nameless told me that in their experience (which is considerable) it had no visible effect on black because it's a protective sealant, and not a colour enhancer.

[London Stone Paving]

Tony
They have a product called enhance plus. We have tested out on black limestone and it enhances the colour very well. Personally wouldn't use anything else

Steve

[Tony McC]

Oh well - their loss. They were invited to provide small samples for the trials and couldn't be bothered to respond, so I ended up using a 50ml sample of 'normal' DryTreat which, as I said, failed to impress.

All the other suppliers were kind enough to submit samples, so they rightly reap the benefits.

[London Stone Paving]

Fair do's tony. Sounds like a missed opportunity. Bad marketing

[eyebrows]

Thanks for getting the info Tony, to be honest they seamed a very helpful bunch on the phone so i wasn't unhappy with them, Just needed some clarification

At the end of the day i'm a Diyer so the more info i can get and the clearer it is before i do a job the better.

One thing that does interest me is steve's comment! Can you walk on dry treat after 20min to apply the second coat?
I haven't tested the weiss on an off cut i have kept as yet, maybe it drys enough to do the same as your doing.

[London Stone Paving]

Eyebrows, I was talking about sealing prior to laying. We've got a little set up where we do it on racks, so walking on it is not an issue for us. If you are talking about walking on paving that's been sealed, it all depends on the weather and how quickly it dries and also the porosity of the stone being sealed. I will check with my supplier and come back to you. the information given on the can though will always be airing massively on the side of caution.