mixing...

[kirk johnstone]

Re: mixing

so kirk would you use a 3:1 on thermalites? i'm abit uneducated when it comes to different mix ratios for different backgrounds.

i would look at it like this mate.
if you are going to put any mix of sand and cement on thermo's it is going to be stronger than them, well unless you mix something like 20-1. so if it was me... i rely upon the mechanical key more than just the render sticking to stuff, so i would rake out the joints and probably key the front of the blocks with my angle grinder, then i would soak the wall untill it would take no more water and then yes... ON with the 3&1 baby ;D

 

[beddy]

Re: mixing

rough [email protected] make up a book to back yourself up. then try and convert us lot..

 

[kirk johnstone]

Re: mixing

no need to call me a b@stard you tw@tty faced little pr@t ;D haha prat didnt even need an @ :

i aint tryin to convert anyone kid, just sayin what me an me old mate miller do. or did in his case

 

[beddy]

Re: mixing

haha. he died when a big lump of his rendering fell on him cus he did it on thermalites. thats right, they existed in 1066 or whenever he wrote that book

 

[kirk johnstone]

Re: mixing

right, before i go to bed... are we all happy that a mix of 3 to fuking 1 is ok to use?

 

[beddy]

Re: mixing

YES, GOODNIGHT!
xx





NO ITS WRONG! ;D

 

[kirk johnstone]

Re: mixing

YES, GOODNIGHT!
xx





NO ITS WRONG! ;D

whats wrong? posting kisses to me :-*

see you all tomorrow xx

 

[Chris W]

Re: mixing

if you use less cement but more waterproofer on a damp job is it more likely to be less or more waterproof? ALL DEPENDS MATE, LABEL USUALLY STATE'S MIX RATIO
i would have thought the less cement you put in, the less waterproof it would be, seeing as the waterproofer reacts with the cement content? or doesnt it then?

what does actually happen if you put old mix back in the mixer? CONTAMINATES THE MIX AND MAKES IT WEAKER
now tell me why?

if you use a 4:1 scratch coat and a 3:1 float coat which one will fall off first? PROBABLY NETHER AS LONG AS YOU KEY IT PROPERLY... WAVY DEEP SCRATCHES
shouldnt it be the other way round though?

what happens if you use soft sand for a scratch coat and sharp sand for a float coat? NOT MUCH AS-LONG AS ITS WELL KEYED, SHARP SAND COMPACTS BETTER SO IT GIVES YOU A STRONGER MORE SOLID FINISH
again, wouldnt this make the float coat stronger than the scratch coat?

what happens if you put render on 30mm thick in one go? ALL SAND AND CEMENT SHRINKS WHEN IT DRIES OUT, WITH THINNER COATS THERE IS LESS CHANCE OF SHRINKAGE CRACKS
nice one,could you add some lime or replace some of the cement with lime to enable you to put it on thicker?

why do damp companies say you shouldnt paint a newly plastered wall with silk paint even though its had 'waterproofer' in it and its been allowed to dry for 3 weeks? PROBABLY JUST AN EXTRA PRECAUTION INCASE THER IS ANY MORE MOISTURE TO COME OUT OF THE WALL, ASS SILK PAINT IS WATERPROOF THE MOISTURE LEAVING THE WALL MIGHT CAUSE IT TO BUBBLE OFF, PERSONALLY I DONT LIKE TO SEE ANY FRESH PLASTER PAINTED WITH SILK AS IT SEEMS TO SIT LIKE A SKIN ON THE FINISH RATHER THAN SOAKING IN
that wall may take up to a year to dry out properly, no 'probably' about it.. incidentally, as long as you mist coat the wall properly before you apply any other paint, you will have a key, dont be putting neat silk paint on bare new plaster! and silk isnt waterproof, its water resistant...

whats the difference between retarder and waterproofer? RETARDER GOES IN THE MIX AND SLOWS THE SET DOWN, WATERPROOFER WONT SLOW IT DOWN BUT IF PUT IN THE SCRATCH COAT WILL SLOW DOWN THE SUCTION GIVING YOU MORE TIME TO WORK THE TOP COAT
if i put waterproofer in a mix, would it re***d the mix?

whats the difference between waterproofer from jewsons and waterproofer from say, sovereign chemicals or triton? NOT MUCH
apart from the fact that damp companiy specified waterproofer has a salt neutraliser/inhibitor in it...

what happens if you add frostproofer to a mix? IT WONT FREEZE, ITS LIKE ANTIFREEZE IN YOUR CAR
It'll also send your mix off bloody damn quick...

is it possible to skim render the same day? YEP BUT WHEN RENDER DRIES IT SLIGHTLY SHRINKS SO GOOD CHANCE SKIM WILL CRACK ALL OVER
so that would be a 'No' then?

does render still stay 'green' for a while even if you use orange sand? YES
Funny that eh? why not 'muddy brown' instead?

hurry up andy :

 

[goody]

Re: mixing

phone a modern plaster/render supplier and tell them the difficult substrate and they will give you the engineered MODERN materials suitable for the task at hand. Easy.

 

[kirk johnstone]

Re: mixing

if you use less cement but more waterproofer on a damp job is it more likely to be less or more waterproof? ALL DEPENDS MATE, LABEL USUALLY STATE'S MIX RATIO
i would have thought the less cement you put in, the less waterproof it would be, seeing as the waterproofer reacts with the cement content? or doesnt it then?

what does actually happen if you put old mix back in the mixer? CONTAMINATES THE MIX AND MAKES IT WEAKER
now tell me why?

if you use a 4:1 scratch coat and a 3:1 float coat which one will fall off first? PROBABLY NETHER AS LONG AS YOU KEY IT PROPERLY... WAVY DEEP SCRATCHES
shouldnt it be the other way round though?

what happens if you use soft sand for a scratch coat and sharp sand for a float coat? NOT MUCH AS-LONG AS ITS WELL KEYED, SHARP SAND COMPACTS BETTER SO IT GIVES YOU A STRONGER MORE SOLID FINISH
again, wouldnt this make the float coat stronger than the scratch coat?

what happens if you put render on 30mm thick in one go? ALL SAND AND CEMENT SHRINKS WHEN IT DRIES OUT, WITH THINNER COATS THERE IS LESS CHANCE OF SHRINKAGE CRACKS
nice one,could you add some lime or replace some of the cement with lime to enable you to put it on thicker?

why do damp companies say you shouldnt paint a newly plastered wall with silk paint even though its had 'waterproofer' in it and its been allowed to dry for 3 weeks? PROBABLY JUST AN EXTRA PRECAUTION INCASE THER IS ANY MORE MOISTURE TO COME OUT OF THE WALL, ASS SILK PAINT IS WATERPROOF THE MOISTURE LEAVING THE WALL MIGHT CAUSE IT TO BUBBLE OFF, PERSONALLY I DONT LIKE TO SEE ANY FRESH PLASTER PAINTED WITH SILK AS IT SEEMS TO SIT LIKE A SKIN ON THE FINISH RATHER THAN SOAKING IN
that wall may take up to a year to dry out properly, no 'probably' about it.. incidentally, as long as you mist coat the wall properly before you apply any other paint, you will have a key, dont be putting neat silk paint on bare new plaster! and silk isnt waterproof, its water resistant...

whats the difference between retarder and waterproofer? RETARDER GOES IN THE MIX AND SLOWS THE SET DOWN, WATERPROOFER WONT SLOW IT DOWN BUT IF PUT IN THE SCRATCH COAT WILL SLOW DOWN THE SUCTION GIVING YOU MORE TIME TO WORK THE TOP COAT
if i put waterproofer in a mix, would it re***d the mix?

whats the difference between waterproofer from jewsons and waterproofer from say, sovereign chemicals or triton? NOT MUCH
apart from the fact that damp companiy specified waterproofer has a salt neutraliser/inhibitor in it...

what happens if you add frostproofer to a mix? IT WONT FREEZE, ITS LIKE ANTIFREEZE IN YOUR CAR
It'll also send your mix off bloody damn quick...

is it possible to skim render the same day? YEP BUT WHEN RENDER DRIES IT SLIGHTLY SHRINKS SO GOOD CHANCE SKIM WILL CRACK ALL OVER
so that would be a 'No' then?

does render still stay 'green' for a while even if you use orange sand? YES
Funny that eh? why not 'muddy brown' instead?

hurry up andy :

you do know this could just go on and on dont you chriss ;D

 

[Chris W]

Re: mixing

thats why i would really like someone to put it to bed once and for all cos this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles


















































































which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles which is why i want someone to put it to bed once and for all because this argument will just go round in circles ;D ;D ;D ;D ;D ;D ;D ;D ;D ;D

 

[Chris W]

Re: mixing

f'cked if i know what happened there.... the space bar pixies just got involved for a mo?

 

[beddy]

Re: mixing

right we need someone to make a post with general ratios/backgrounds etc then lock the f**k*r!

 

[kirk johnstone]

Re: mixing

am off back to work now just come back for my tea after a nice long day of sand and cement top coating smooth finish, now i have got a little bathroom ceiling to do around the corner from mine, am gagging for a beer

speak to you later mate

 

[kirk johnstone]

Re: mixing

right we need someone to make a post with general ratios/backgrounds etc then lock the (french word)er!

f u k me how many times?

right it goes like this...

create a key on the wall, wet the wall, mix 3-1 with feb and waterproofer stick it on and scratch, then if you want it a top job lay screeds and float (you dont have to do this but i do on big walls because when the sun hits it some times they are all over the show but this way it will be very flat) this is also a mix of 3-1 with waterproofer and feb, then top coat goes on nice and thin also 3-1 with no waterproofer and 1/2 a lime in it instead of feb as i find it is easyer to rub up this way. just rule it off and rub it up.

before each coat let the back coat set and dry out and then wet it down before the next coat goes on.

this is what i do and it works very well for me. never, NEVER had a problem doing this! even with a weak background its the key that holds it on.

 

[beddy]

Re: mixing

the bloke i work with does it 4/1 5/1 and has never had a problem with that kirk. so whos right?

 

[richie]

Re: mixing

have a poll but 3/1 too strong

 

[carlos]

Re: mixing

right we need someone to make a post with general ratios/backgrounds etc then lock the (french word)er!

This is what I wanted to achive when I started this!!!!!

 

[Chris W]

Re: mixing

andy 'n church'll sort it.. check the noob section in a week...

 

[kirk johnstone]

Re: mixing

the bloke i work with does it 4/1 5/1 and has never had a problem with that kirk. so whos right?

well i dont think its a case of whats right and whats wrong mate, it will all be ok ie.. 3-1, 4-1, 5-1 i even think a mix of 9-1 will be ok but the way i look at it is a stronger mix will last longer, cement is what binds the sand together (binder) and the more you bind something together the longer it will withstand the weather. the truth is if you mixed a 6-1 mix it will probably still be there long after you are dead... BUT not quite as long as my 3-1 mix ;D

if you read any book on mix ratio's they will recommend that you use a stronger mix for more extreme conditions, this tells us that a strong mix will last longer than a weak mix, now if you dont live on the coast and you wouldnt say that the weather was extreme, this dosnt mean that a strong mix will fall of! it just means that you can GET AWAY with a weaker mix. and thats it. oh and if you are still wondering about weak backgrounds then just think to yourself KEY, DEEP MECHANICAL KEY! and like essex andy has said in one of his posts.. he has renderd over thermolite block and its still there 15 years later which proves that all this shyte about weak backgrounds dont mean much anyway! because as you all know the only thing you can mix that will be weaker than a thermolte block is hot chocolate.


hope this clears it all up fore everyone

 

[kebab king]

Re: mixing

Mechanical key or not, a strong mix can blow of the surface of your celcons, then no key is going to stick ya render on.

 

[carlos]

Re: mixing

kirk your just repeating your self mate

 

[richardbrown]

Re: mixing

speak to celcon .. they spec themselves 6-1 scratch 7-1 top

 

[carlos]

Re: mixing

speak to celcon .. they spec themselves 6-1 scratch 7-1 top

Thank you Richard this is the sort of thing I was after.

 

[pftmonojetman]

Re: mixing

Gotta say it myself if your render is harder than your back ground your asking for trouble.

 

[kebab king]

Re: mixing

Never mind, plenty of hack off and re renders to do.

 

[carlos]

Re: mixing

So when your goning over a solid backgroung like say dense concret block you can pretty much use what you like?

 

[pwi]

Re: mixing

Carlos as said in a previous post to many guys turn up and mix what the hell they want over blocks it should be 4-1 waterproofer I like a scoop of lime aswell top coat 5-1-1 some people add a little bit of water proofer to this but that's just opening another tin of worms but always remember to gauge your mix in a bucket so every mix is the same and always gauge waterproofer properly

 

[kirk johnstone]

Re: mixing

tell you what, why dont we all just do a 6-1 scratch and a 7-1 top then?

 

[ziggy2]

Re: mixing

It's all to with different expansion and contraction rates with temperature as I understand, weaker renders & substrates etc have larger margin of movement than a harder one, therefore, if you lay a harder mix over a weaker one the weaker mix underneath will move more than the harder mix in turn causing it to fail at some point in the future.

 

[essexandy]

Re: mixing

It's all to with different expansion and contraction rates with temperature as I understand, weaker renders & substrates etc have larger margin of movement than a harder one, therefore, if you lay a harder mix over a weaker one the weaker mix underneath will move more than the harder mix in turn causing it to fail at some point in the future.

Totally agree. I've just put together a little piece on rendering as Church asked me to but am having a problem uploading it to the forum at the moment, as soon as I can get in on I will sit back and take all the flak that will undoubtedly get thrown my way :-[

 

[ziggy2]

Re: mixing

Ha! Nothing like it, you can learn by wisdom or experience, wisdom is the knowledge gained through others experience or experience is the knowledge gained through sweat and f**k ups on your own! 8)

 

[church]

Re: mixing

How much have you wrote !!!!!!! Andy ;D ;D ;D

 

[spunky]

Re: mixing

what happens when we put a 2-1 slurry on the wall flick a 2-1 tyrolean coat over it whilst its tacky then go over it with a 4-1 scratch coat and a 5-1-1
over celcon/thermalite ???

 

[essexandy]

Re: mixing

How much have you wrote !!!!!!! Andy ;D ;D ;D

I'm now working on volume three