Floating bonding backing coat
I'm having a bit of trouble using the plastic float with Thistle bonding
coat. I thought I was getting it with sand and cement ...
I'm using the bonding coat on some messy half painted half patched up walls that I treated with wickes bonding agent. It seems that by the
time the surface is dry enough to use the float, the main body of plaster has got to dry to do anything with? Depending on when I attempt to float I an either having no effect because it's too hard or it's all getting stuck to the float and coming off the wall.
Do you have any suggestions?
Bonding coat is not the easiest to float! (Sand & cement /lime on the other hand just loves to be floated!)
Therefore do as much as you can with the straight edge, to leave very little for the float to do. Then it is a case of catching it just at the right time - if there is not very much suction and it is 'hanging wet' then the ideal time is just as it is starting to set - but you won't get long. Then when it has really firmed up you can finish off with your trowel (just make sure you don't push it out of shape).
If it is drying fairly quickly then float as soon as you can, and flick or spray a little water on the wall to help lubricate.
Do make sure the surface of the float is smooth, by rubbing off and smoothing any square pattern kind of texture that may be there from manufacture, as this will definately not help. A smooth paving slab or breeze block will do the trick. Also rub all corners slightly so that
everything is rounded and this will help prevent it from getting stuck.
Hope this helps
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