How to speed up or slow down plaster working time

Plaster working time ( tricks of the trade )
I know that cement truck delivery drivers carry a bag of sugar in their truck in case they get lost, or get held up, I don't know if sugar will work with plaster to slow it down though ???

[@drabhand]

As a former dental tech, we called dirty water or water with set plaster particles, slurry. The more particles, the faster the set and the weaker the plaster, so a light mix is best. To slow it down we used borax, this can effect strength, but again the more you use the slower it sets. Trial and error/pre-experiment is very important with borax, as if you use too much the plaster may not set properly at all or has a dusty finish. I used both of these methods during renovations, using commonly available wall plaster, to great results. These are the only two additives I would recommend.

[@shaun3248]

Citric acid or lemon juice to slow down.

[@jonelliott4985]

Add alum to speed it up or dextrine... to slow add some let or plasterer Lyme (hydrated Lyme but you should leave it to soak before you stir and apply to the wall it's basically old fashioned Lyme putty mostly used in wall art carving in situe or for casting ceiling roses, arcitraving, coving, dedos or picture rails in situe using a roller jig to apply to wall and carve whilst it's wet....milk is not good it creates mold spores in the wall coating same with urine which is disgusting practice no one ever did that unless they were a cowboy and vindictive little cnut never heard of lemon juice or citric acid being used but I guess it might work however it would no doubt cause mild spores to grow in time within the walls which is hazourdous to a person's health... I was in plastering for a long time and know quite a bit bout it traditionally we used sand and lyme to make backing plaster try it and see how much longer you can work with it as aposed to sand and cement you can work with it longer as it remains playable whilst it is being moved around if it stiffens a bit add some water to knock it back but be warned you must be careful as Lyme is highly corrosive wear gloves or coat your hands in baseline to prevent it being in prolonged contact with your skin other wise you might find it melting off your skin before you know it I know had a little accident screwing a floor with Lyme in the mix I didn't know till I'd finished went for a shower and found I'd melted all the skin off my knees from knealing on it whilst leaving the floor screed in a large 20' x 25' basement room it was bad the raw flesh was still reading high alkaline for 5 hours after hospital surgically scrubbed them and ran ice water on them constantly ... basically strong alkaline is same as strong acid it will burn through literally cooking tissue and flesh until it is neutralized and oh balance is normalised ...I hadn't noticed it had soaked through my cargo trousers and knee pads didn't feel any pain till I had took off my trousers and raw flesh was exposed to the air hence why I say be careful cause you may not notice any pain or damage till it's too late and the damage is already done

[@Liliarthan]

Wow ouch! That sounds awful! Did your skin grow back ok? Must have been a painful recovery

[@moedem]

Dr oetker cream of tartar makes plaster set slower

[@1966human]

Ok good one never heard of it though, would be interesting to know how it effects the strength of the plaster

[@moedem]

1966human my mate here in the UK uses it every summer , he shown me a small mix he made compared to a normal mix and the one with the tartar took around 25-35 mins longer till it was unusable to spread on wall , its in small sachets it’s not cream as such it’s in a powder form

[@Mr5Adrian]

@@moedem what quantities of cream of tartar /15 kg bucket?

[@mohameddahb3073]

Please tel me .what does mean pist.matirial

[@1966human]

Just urine man

[@milohenry1233]

Pva

[@1966human]

What does it do?