The Brew Cabin

Posted: **Mon Jul 25, 2016 10:58 pm**

Hi
I have just finished laying a Bradstone smooth sandstone patio and have left 2mm gaps. All laid on a full bed of 1:4 cement / sharp sand, and looking pretty awesome I have to say...
I have now attempted to use gftk 815 compound to do the jointing, after consulting various instruction sheets, videos, personal recommendations etc. To my surprise it did not form the smooth creamy slurry I was expecting (mixing times 3mins pre and 5mins post adding the hardener) but rather a flocculent granular mass which was very difficult to push around with the squeegee, refused to go down the gaps, and after about half an hour of struggling I pulled the whole lot off the paving and dumped it. I used copious water before, and during the attempted spreading, but the consistency was nothing like that seen on the gftk website or the NCC Streetscape video.

SO questions :

1. Could this have been a bum batch of vdw 815?
2. Is vdw815 too coarse for 2mm joints? I was recommended this by Kebur
3. Is vdw815+ a finer mix and thus more appropriate? If so, where can I get some? Google is no help, and it appears on the German version of the gftk website, but disappears once you switch to the English version.

All help welcome

Ta
IAn

Posted: **Tue Jul 26, 2016 6:31 am**

i think you will find a 2mm joint is to small for that product, MSH

Posted: **Tue Jul 26, 2016 7:12 am**

Many thanks
AS I suspected, though the handling qualities of the vdw 815 were surprisingly difficult compared to all the videos. I was expecting a much easier flow ... It was like trying to push crystallised honey around. It felt as if the epoxy resin had started going off prematurely, as there was virtually no "flow" to the product, which is independent of gap size.... Hence the thought that this was an old batch - I know it had sat at KEBUR for some weeks/months as they had trouble finding it under a pile of other products....

Anybody got any info on the vdw 815 PLUS as I think this is finer than the vdw 815...?

Posted: **Tue Jul 26, 2016 8:34 am**

Hello Ian

Who at Kebur recommended the vdw 815 for 2mm narrow joints? as we state on our website a minimum of 3mm and on our Smooth and Honed Sandstone we always recommend that the paving be laid with a 5mm minimum joint. Did you try and use the 815 when the temperature was hot? We always find that the workability of vdw 815, 800 and 850 is best, first thing in the morning or late afternoon and avoid using it during the day especially this time of year as we have found it to cure quicker. We also recommend on our website and instruction video that you need at least 2 or 3 guys using the product one mixing, one on the squeegee and another applying the water and not really suitable for a one person application. We have only been stocking the 815 for a couple of months so I can assure you it was not an old batch. If you need any advice on the product you can always call me direct on 07832382689 or Gary from NCC is always extremely helpful, regards Dave

Posted: **Tue Jul 26, 2016 10:40 am**

If you'd rather email Gary than call him .....

....the contact details are on their website[

Edited by Tony - Don't post email addresses in the Brew Cabin unless they are your own and you love spam.

Edited By Tony McC on 1469536041

Posted: **Tue Jul 26, 2016 5:31 pm**

Many thanks to Dave at KEBUR and Carl from NCC who spent a deal of time talking with me today ... Carl's advice was to use the 815 for the 2mm gap, but it will take quite an effort to get it to go down, so mix a quarter to a third of a tub at a time only to allow this to happen before it gets 'tacky' - this works quite well, but the workable time is actually quite short with this product even with copious amounts of water, but at least there is progress , and I will do the patio in about six sections now ( about 10 sq m per time) which seems to be manageable. Having wasted about a full tub of 815 I will need another one from KEBUR now! Don't suppose I could get a discount for trying hard could i Dave...!

Many thanks
Ian

Posted: **Tue Jul 26, 2016 6:06 pm**

2mm joints?
that is tight
most flags have a 2mm tolerance
LLL

Posted: **Wed Jul 27, 2016 8:40 am**

Hello Ian,

I would be happy to offer a special discount to yourself as you have wasted a tub, please call the sales office and say you have spoken to me, alternatively I am in at Kebur all day Saturday so you can either call me or pop in and I will sort it out for you.

Regards

David

The Brew Cabin

Gftk vdw 850? 815? 815+ ? - Which jointer to use?