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Unable to cut small piece of drywall perfectly

Unable to cut small piece of drywall perfectly

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  #1  
Old 02-01-17, 05:55 AM
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Unable to cut small piece of drywall perfectly

I am trying to cut a piece of drywall from a large piece of drywall I only need a small section to patch a hole. I attached a picture to show what I am trying to accomplish

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I only need the piece bordered by the red lines. But when I cut it and try to snap it, the paper in the back of sheet comes apart and now the sheet has the gypsum showing with no paper to hold it in place, so it has no integrity. Is it possible to snap a small section like that out of a big piece? Or do I need to score all the way across the blue and orange line to be able to snap this small piece? Do I need to score the full length of the sheet until I get 2 edges of the patch I need exposed and then I will be able to snap it off cleanly?
 
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  #2  
Old 02-01-17, 06:00 AM
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You will have to cut all the way through the board on one line also cut the back paper along that line. Have the other cut ready also.
 
  #3  
Old 02-01-17, 06:21 AM
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Ok so it's almost impossible to cut a square out of a sheet or larger piece of drywall perfectly. You always need to cut the sheet to have at least 3 sides of the required piece exposed and then you can score and snap the missing 4th side, is that it?
 
  #4  
Old 02-01-17, 06:32 AM
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You can only cut and snap one side, if more sides need to be cut you need to use a saw on them first.
You don't need perfectly square cuts, the tape/mud will hide easily hide minor discrepancies .
 
  #5  
Old 02-01-17, 06:36 AM
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I could do it with my oscillating saw or even a drywall saw.
 
  #6  
Old 02-01-17, 06:42 AM
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Cutting Small Piece of Drywall

I use a jig saw with a coarse blade. Keep the blade for future drywall cuts. Laid flat on saw horses works best.
 
  #7  
Old 02-01-17, 07:52 AM
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When using a drywall saw, should you drill a starter hole or if you push the drywall saw through the paper and gypsium, you shouldn't damage the piece?
 
  #8  
Old 02-01-17, 08:32 AM
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If you were cutting out an outlet, you would just push the saw through striking it with the palm of your hand. For your piece, you could start cutting on the edge.

This is not that hard. Score one red line with your knife, cut the other red line with a saw. Snap the piece downward 90 degrees and the uncut paper will be like a "hinge" on the back side of where you scored it with a knife... then cut along that crease in the paper.
 
  #9  
Old 02-01-17, 08:52 AM
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Thanks, I will try it tonight. I know this shouldn't be that hard, I am beginner hence the questions.
 
  #10  
Old 02-01-17, 08:59 AM
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I think the mistake some beginners make is trying to snap the drywall the wrong way after they score the front. Pretty sure you can do this.
 
  #11  
Old 02-01-17, 11:06 AM
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ya I was scoring the front and breaking from the back but I was trying to snap 2 lines at the same time, which don't work. I'll cut one with the drywall saw and snap the other.
 
  #12  
Old 02-01-17, 11:13 AM
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You are actually scoring both sides. Score, break, score, snap.
 
  #13  
Old 02-01-17, 11:16 AM
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Ya that's what I was trying to do, I scored both red lines and then tried to snap the piece and then score the back. But the piece was too heavy and it would rip the back paper ruining the integrity of the piece.
 
  #14  
Old 02-01-17, 11:21 AM
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By "score both sides" I mean you score both sides of the ONE SIDE that you are cutting with the knife.

Cut one of your red lines with the saw.
Cut the other red line with the knife.
Break it downward 90 degrees where you scored it.
Score the back side where the paper is bent 90 degrees.
Snap it back up/off.
 
  #15  
Old 02-01-17, 11:37 AM
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Exactly that's what I am gonna do. What I was doing wrong the first time was scoring both red lines on the front instead of cutting one red line with the saw and scoring one red line with the knife, then after I had scored both red lines I tried to break it downward 90 degree and score the paper on the back side but this didn't work since you can only score/snap one side. I think the info I was missing was, if the piece has multiple sides, then those need to be done with the saw first and the remaining side can be scored, snapped the usual way.
 
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