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plstering
GUIDE FORE FORMING QUOINS
(this is the way i do it, there is more than one way tough)
first of all get some lengths of wood (the same thickness that you want the quoins). attach the wood horizontally around the bottom and the top of the corner you are going to work on, you will use these as thickness rules.
it would be best to drill, plug and screw these thickness rules as it will be easier to take them away afterwards.
the wall should have already been scratch coated and now you can start to build out to the correct level of your rules, if you are building out more than 3/4'' then you will need to use dryers (this is sand and cement mixed to the same ratio as what you are using fore forming the quoins only without water, a dry mix), the reason for this is if you try to build out to thick it will just sag and drop of the wall. so put a coat on, throw some drymix (dryers) at it, just like pebble dashing then put another coat on, throw more dryers and then another coat, continue until you are at the right thickness then use the thickness rules at the top and bottom of the wall to get your quoins straight flat and true. now let the ruled sand and cement firm up and when it is ready rub it up with the float. now the next step is to mark out your quoin stones.
measure the distance from the top of the wall to the bottom and divide this number by the amount of quoins that you want, then put a little horizontal line in the sand and cement with your small tool at the hight of all of the joints. now with the aid of a small spirit level cut your small line into the sand and cement all the way back to the scratch coat (do this for every joint on both sides of the corner).
right now the hight of the quoins is sorted you need to work out how wide you want them, they are normally twice as wide as the hight, so if your quoin is 10'' high then it would be 20'' wide when you are looking at it square on so mark it out and cut in the vertical line on both sides of the corner.
ok next step, the quoins are staggered so when you look at them square on from one side they step in and out (the bit that steps in is the depth of the quoin on the other side of the corner) now the depth of the quoin is normally two thirds of the width so in this case the depth would be about 13".
you can now mark this out using the same method as before but only cut through every other quoin and do the opposite on the other side.
you now have them all marked out and can now go to work on cutting the joints, on the size of the quoin we are talking about i would cut off about an inch and a half off each stone, so you need to mark out 1 1/2" each side of every line you have cut in. mark these new lines very gently in to the surface first as these will be getting cut at an angle to form the chamfer aroun the edge or each quoin, once marked you can proceed to cut out the chamfered joints with the aid of a small feather edge of a frenchman (piece of wood with a 45% chamfer cut along the edge), take it nice and slow and only cut a small bit at a time. they should be taking shape by now.
once done they might just need a bit of touching up with the float.
take out the rules and job done
(this is the way i do it, there is more than one way tough)
first of all get some lengths of wood (the same thickness that you want the quoins). attach the wood horizontally around the bottom and the top of the corner you are going to work on, you will use these as thickness rules.
it would be best to drill, plug and screw these thickness rules as it will be easier to take them away afterwards.
the wall should have already been scratch coated and now you can start to build out to the correct level of your rules, if you are building out more than 3/4'' then you will need to use dryers (this is sand and cement mixed to the same ratio as what you are using fore forming the quoins only without water, a dry mix), the reason for this is if you try to build out to thick it will just sag and drop of the wall. so put a coat on, throw some drymix (dryers) at it, just like pebble dashing then put another coat on, throw more dryers and then another coat, continue until you are at the right thickness then use the thickness rules at the top and bottom of the wall to get your quoins straight flat and true. now let the ruled sand and cement firm up and when it is ready rub it up with the float. now the next step is to mark out your quoin stones.
measure the distance from the top of the wall to the bottom and divide this number by the amount of quoins that you want, then put a little horizontal line in the sand and cement with your small tool at the hight of all of the joints. now with the aid of a small spirit level cut your small line into the sand and cement all the way back to the scratch coat (do this for every joint on both sides of the corner).
right now the hight of the quoins is sorted you need to work out how wide you want them, they are normally twice as wide as the hight, so if your quoin is 10'' high then it would be 20'' wide when you are looking at it square on so mark it out and cut in the vertical line on both sides of the corner.
ok next step, the quoins are staggered so when you look at them square on from one side they step in and out (the bit that steps in is the depth of the quoin on the other side of the corner) now the depth of the quoin is normally two thirds of the width so in this case the depth would be about 13".
you can now mark this out using the same method as before but only cut through every other quoin and do the opposite on the other side.
you now have them all marked out and can now go to work on cutting the joints, on the size of the quoin we are talking about i would cut off about an inch and a half off each stone, so you need to mark out 1 1/2" each side of every line you have cut in. mark these new lines very gently in to the surface first as these will be getting cut at an angle to form the chamfer aroun the edge or each quoin, once marked you can proceed to cut out the chamfered joints with the aid of a small feather edge of a frenchman (piece of wood with a 45% chamfer cut along the edge), take it nice and slow and only cut a small bit at a time. they should be taking shape by now.
once done they might just need a bit of touching up with the float.
take out the rules and job done
