What is "5 cut method"?

[Steve Kohn]

I just got through reading another reference to the 5 cut method of getting a square cut. Pardon my ignorance but can someone explain it or send me to a reference.

Thanks.

[Lenny Baledge]

In my case, I usually have to cut 5 times before it's actually square!

Lenny

[John Hulett]

I'm not real familar with it myself, but had found reference to this in a past post and saved it as a favorite

http://www.thewoodshop.20m.com/five_cut_method_swf.htm

- John

[glenn bradley]

To my view the method is more a way to check that you are getting a square cut so you can adjust as required. Not really a way to get a square cut.

[Mike Henderson]

I've heard this term used in veneer work. Let's say you have a panel that you put a four piece match on with the seams running towards the corners. However, for whatever reason, the seams didn't match up with the corners - maybe the veneer slipped when you glued it. Now, what you want to do is to cut the panel square so that the seams in the veneer are running to the corners. There's a technique that will allow you to cut the panel with five cuts such that when you finish, all the lines will be aligned with the corners (and the piece will be square by definition).

I don't know exactly what that technique is but I developed my own technique to do the same thing, which I'll describe here.

First let me define a “line”. These are the interfaces between the pieces of triangular veneer. Let me further define them as running from the center outward which means that we have four lines on the piece (instead of two). We can assign a number to these lines, perhaps 1, 2, 3 and 4, assigned in order and clockwise.

If the lines {1,3} and {2,4} are orthogonal, we can draw a circle within the lines centered on the intersection of the lines, and connect the points of intersection of the lines and the circle to produce a square. That is, each line must be of equal length.

Since each line must be of equal length, we must start with the shortest line. Find that shortest line with a ruler, dividers, compass, or marks on a piece of wood. Now transfer this distance to the adjacent line (assume 1 is the shortest line, and transfer that length to line 4 or 2 – I’ll use these numbers in the rest of my discussion.).

Cut the block along the line between the end of line 1 and the mark on 2 or 4 (Let me assume for example sake that you cut along the line 1 – 2). This provides a reference edge. With the {1,2} edge against the sled, cut the {2,3) edge using the end of the 2 line as the reference point. Rotate and use the {2,3} edge against the sled, cut the {3,4} edge using the end of the 3 line as a reference. Continue to the remaining edge. If the cuts were made without too much error, and the {1,3} {2,4} lines really are orthogonal, and if the sled is square to the blade, all the lines will be in the corners.

Mike

[Joe Jensen]

I just got through reading another reference to the 5 cut method of getting a square cut. Pardon my ignorance but can someone explain it or send me to a reference.

Thanks.

The 5 cut method is a way to check how sqaure your crosscut setup is. Take a piece of plywood. Cut a kerf width off a side. Rotate to put that fresh cut against the fence and cut again. Repeat cut and rotate until all 4 sides have been cut. Then rotate one more time and cut 1/2" off. Then take that cutoff and mark one end "A" and one end "B". Cut the cutoff in half and then line the pieces off to see if "A" and "B" are the same width. If not, then your setup is not really square. The 5 cut method will multiply any error in your setup by 4 or 5 times. It's a great way to adjust...joe

[Mark Carlson]

I use this method to check for 90 degrees on my cross cut fence to the blade. The nice thing about it is you can just break the last cutoff in half place the A and B ends together (on their sides) and use your finger to see the difference. The difference will be 4 times the amount your fence needs to be adjusted. See the theworkshop site for a detailed description with flash.

~mark