primer peeling

[Mike Mike]

weber came down today with a 4 to 1 Pr 360 which they applied to test area after sanding clean ,i then applied a 4 to 1 of my pr360 next to it ,this evening to the eye they are not the same colour although still drying ,the weber 4 to 1 is fine but my 4 to 1 is if you put your fingernail on it is peeling.Same product ,same mix but both not working the same ?

I,m told that the Supaflo should have been mechanically sanded but cemex told me not to but in any event having seen the test area sanded and it is still peeling ?

I do wish i had gone with as different primer ,in fact we have done a test area on a no sanded patch with norcross and it is fine

Dont know where this is heading but how would you remove all this primer ,tried with a orbital 80 grit and it would take years .
Is there a machine out there ?
Ajax i have tried phoning ,will try you Monday
Thanks

Yes. Try one of these (or similar). HSS Hire - Commercial Floor Finishing Sander Hire and Rent

Talk to them about what discs they have available. Forget sandpaper for this application. You want a disc with 5 or 6 stone cups on it to really grind the top layer of the screed off. Can't remember how big an area you have, but you will be able to completely sand a couple of hundred m2 in a morning with one of these.

 

[Alan M]

sorry m8 for the dose you have on your hands.
presumably given that your bottle isnt doing what theirs is you will get compensated for it.

as for removing the primer. (worth asking webber if they have a primer remover)
by the sounds of it , it is like a solid layer on top of the floor.
i would get one of those scrapers for wall paper that are really flexable and try and get in under it.
if that wont work you will have to sand it off, maybe one of those sanders for wooden floors would speed up the removal.
i would guess that that primer would clog the abrasive fairly fast.
do you know anyone with a festool rotex sander . they have great sandpapers for sanding stone and paint etc(saphire ,granat ,or crystal should work) and with vac very little dust (almost none)

 

[Mike Mike]

weber came down today with a 4 to 1 Pr 360 which they applied to test area after sanding clean ,i then applied a 4 to 1 of my pr360 next to it ,this evening to the eye they are not the same colour although still drying ,the weber 4 to 1 is fine but my 4 to 1 is if you put your fingernail on it is peeling.Same product ,same mix but both not working the same ?

I,m told that the Supaflo should have been mechanically sanded but cemex told me not to but in any event having seen the test area sanded and it is still peeling ?

I do wish i had gone with as different primer ,in fact we have done a test area on a no sanded patch with norcross and it is fine

Dont know where this is heading but how would you remove all this primer ,tried with a orbital 80 grit and it would take years .
Is there a machine out there ?
Ajax i have tried phoning ,will try you Monday
Thanks

This I think is the most popular brand and model in the U.K. http://www.spe-int.com/multipurpose...purpose-preparation-system.aspx?prid=19&cid=4

Here's one for sale. SPE STR701 Multi Purpose Floor Preparation Machine | eBay

The special drive board you need is abou £150 ish. Everyone should have a rotary floor machine in their tool kit, use it on all freshly poured screeds to get a good key.

There are cheaper ones, Numatic do some, but don't know about accessory drive boards, but you could ask them. You see them for sale for a couple of hundred quid every now and then. I use Janser and Nilfisk for sanding all floors before tiling / floor laying. LOL, the ONLY application they are NOT used for is sanding wooden floors, so ironic that HSS call it a wooden floor sander?? Oh well...

 

[chequers]

This I think is the most popular brand and model in the U.K. http://www.spe-int.com/multipurpose...purpose-preparation-system.aspx?prid=19&cid=4

Here's one for sale. SPE STR701 Multi Purpose Floor Preparation Machine | eBay

The special drive board you need is abou £150 ish. Everyone should have a rotary floor machine in their tool kit, use it on all freshly poured screeds to get a good key.

There are cheaper ones, Numatic do some, but don't know about accessory drive boards, but you could ask them. You see them for sale for a couple of hundred quid every now and then. I use Janser and Nilfisk for sanding all floors before tiling / floor laying. LOL, the ONLY application they are NOT used for is sanding wooden floors, so ironic that HSS call it a wooden floor sander?? Oh well...

Just spent two days sanding with a standard floor sander i managed to get from the local hire shop before they closed ,the p24 grit is getting it off but anything higher no chance .
It is a hellish job with lost of dust
I would like to say a big thank you to everyone who has contributed to this posting ,it is very much appreciated .
Once it is all off i dont know about reapplying the Pr360,when webber came down on Fri they said the surface should not be shiney but their test sample area is! .
I am wondering about what Primer to use that is the best , i had looked long at the eco prim and the Super G ,but i have done a test patch of the Norcross Prime bond which is a form of SBR and that seemed Ok .
This has been a nightmare job but better than the tiles failing

 

[bugs183]

Well done Chequers for keeping your cool and doing this job properly, most would say damn it we've started it'll be alright!!.

These screeds are causing so many people problems, which is a real shame as they are so nice to work on. I've been recommending them to builders and so far have had no problems, i've been sanding and priming them with a dilute epoxy epoxy primer and that stuff doesn't shift, but i'm waiting now for someone to say you can't use that because it contains some new ..ide chemical that will react with it.
I will be swapping to the gypsum based adhesives on the next jobs as this is the direction that these floors dictate.
Once again Ajax has been an amazing help, with well thought out and well written guidance on these matters, he's being a bit of a hero on hero on here.
Good luck matey!

 

[Ajax123]

Well done Chequers for keeping your cool and doing this job properly, most would say damn it we've started it'll be alright!!.

These screeds are causing so many people problems, which is a real shame as they are so nice to work on. I've been recommending them to builders and so far have had no problems, i've been sanding and priming them with a dilute epoxy epoxy primer and that stuff doesn't shift, but i'm waiting now for someone to say you can't use that because it contains some new ..ide chemical that will react with it.
I will be swapping to the gypsum based adhesives on the next jobs as this is the direction that these floors dictate.
Once again Ajax has been an amazing help, with well thought out and well written guidance on these matters, he's being a bit of a hero on hero on here.
Good luck matey!

No pressure there then.... 🙂

Sorry I mised your posts at the weekend. For future reference I think you would have been better to use a sot blasting machine to remove theprimer. Would have been much quicker and cleaner. However that bit sounds likeit is done now.
I guess the advent of primer less systems to go on anhydrite is a real bonus when you see stories like this.

What you doing regarding restocking the tiles. If it were me I wold deffo go with a primerless adhesive.

 

[Jamiewh]

I’ve had a similar problem. I levelled my hallway using no nonsense floor screed. Then I primed it Bostik Cempolay Universal Primer Blue Pigment 2.5Ltr to get it ready for tilling but in a few areas, the primer has peeled off?