Math Class
- Thread starter Kevin
- Start date
It's not random.
The 0 mark is on one side.
The 9 mark is on the other.
So, on a diagonal you're measuring 9" across the board (in your case it would be 0 and 12 but my paper can't go to 9 11/16 wide :) By putting a mark at 3 and 6 *on the diagonal* you're marking the 1/3 points of that diagonal. It doesn't have to be corner to corner, it just has to go from top to bottom (or left to right). It does have to cross the entire board.
Trust me. If you take one of your blanks that you've measured and marked and take a ruler (or tape measure) and put the 0 on one side and the 12 on the other, the 4" and 8" marks on the ruler will line up with your measured lines.
If you needed to divide the board into 4ths in your case you'd put the marks on 3, 6, 9 (in the case of the above picture I'd change to 8" and mark 2,4,6 or 10" and mark 2.5, 5, 7.5)
The trick in doing this is to use a diagonal that's a multiple of the number of pieces you want to divide into that's larger than the width of what you want to divide.
In your case you want 3 pieces and your width is 9 11/16. The next higher multiple of 3 is 12. So you put the 0 on one side, the 12 on the other so you're spanning the entire width of the board and put your marks on the 4 and 8. You've now divided the line crossing your board into thirds. Now, using those marks draw lines through those marks that are parallel to the edges you just put the 0 and 12 on and you've divided the board into thirds.
In the case of the example the square is only 7 11/16. The next higher multiple of 3 is 9. So I put the ruler across the square with 0 on one side and 9 on the other then mark at 3 and 6. Drawing lines that are parallel to the top and bottom that pass through the points I just drew will split the square into thirds.
And of course the easiest thing to do is once you've done this once on a scrap piece that's the same size as your blank you just cut off one of those thirds and use it as a straight edge to mark all your blanks and never measure again. Presuming, of course, that you're doing multiples of the same size.
The 0 mark is on one side.
The 9 mark is on the other.
So, on a diagonal you're measuring 9" across the board (in your case it would be 0 and 12 but my paper can't go to 9 11/16 wide :) By putting a mark at 3 and 6 *on the diagonal* you're marking the 1/3 points of that diagonal. It doesn't have to be corner to corner, it just has to go from top to bottom (or left to right). It does have to cross the entire board.
Trust me. If you take one of your blanks that you've measured and marked and take a ruler (or tape measure) and put the 0 on one side and the 12 on the other, the 4" and 8" marks on the ruler will line up with your measured lines.
If you needed to divide the board into 4ths in your case you'd put the marks on 3, 6, 9 (in the case of the above picture I'd change to 8" and mark 2,4,6 or 10" and mark 2.5, 5, 7.5)
The trick in doing this is to use a diagonal that's a multiple of the number of pieces you want to divide into that's larger than the width of what you want to divide.
In your case you want 3 pieces and your width is 9 11/16. The next higher multiple of 3 is 12. So you put the 0 on one side, the 12 on the other so you're spanning the entire width of the board and put your marks on the 4 and 8. You've now divided the line crossing your board into thirds. Now, using those marks draw lines through those marks that are parallel to the edges you just put the 0 and 12 on and you've divided the board into thirds.
In the case of the example the square is only 7 11/16. The next higher multiple of 3 is 9. So I put the ruler across the square with 0 on one side and 9 on the other then mark at 3 and 6. Drawing lines that are parallel to the top and bottom that pass through the points I just drew will split the square into thirds.
And of course the easiest thing to do is once you've done this once on a scrap piece that's the same size as your blank you just cut off one of those thirds and use it as a straight edge to mark all your blanks and never measure again. Presuming, of course, that you're doing multiples of the same size.
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I think that there's an app for that.
- Thread Starter Thread Starter
- #44
Okay that's all it took . . . genius! Thank you!
- Thread Starter Thread Starter
- #45
Ken I didn't read past those two lines do I need to - is there other info in there or just trying to get through my thick skull? Pressed for time right now . . .
Just that the lines you draw through the marks need to be parallel to the sides you put the 0 and 12 on.
And a shortcut - do this on a scrap of the same size as your blanks, cut it out, use it for a straightedge and don't worry about measuring again (presuming your blanks are all the same size.)
And a shortcut - do this on a scrap of the same size as your blanks, cut it out, use it for a straightedge and don't worry about measuring again (presuming your blanks are all the same size.)