Using 2 rulers to measure when cutting
 

I know some people use 2 rulers lined up somehow when cutting out fabric. I've tried but can't figure out out to line them up. They remove the 2nd ruler before they make the actual cut. Any help?

i will use them as a 't' square to straighten or end to end to extend for long strip for border strip. line them up to continue the cut w/o moving fabric. i don't like seams in my borders.

I use 2 rulers all the time when cutting fabric with a rotary cutter, especially when the fabric is folded. It is very important to position the cutting ruler so it is at an exact 90-degree angle to the fold. If that angle is off, you get the dreaded V bend at the fold. I am right-handed, so when I cut the bulk of the folded fabric is to my right. The cutting ruler is at the left edge of the fabric. This means most of my cutting ruler line is off the fabric, to the left. What I do is take a second ruler (the widest one I have that has a long line marked on it) and place it to the right of my cutting ruler. This way I can position a line on the second ruler along the fold of the fabric. Once I do this, I hold that second ruler in place while I butt my cutting ruler up against the edge of the second ruler. This ensures that my cutting ruler is at the most accurate 90-degree angle I can get. I will see if I can find a Youtube video that demonstrates this.

Edit: Found this video which, at about 3 minutes in, starts showing what I have described above. I have not watched the entire video so don't know if I do all the other things she does, but this 2-ruler method is what I do when I start cutting. I don't do this with every cut -- always with the first cut, and then any time I want to check on the squareness of the fabric edge I am cutting.
https://www.youtube.com/watch?v=42w5fuQmqSI

Either they need an 8 in strip and only have say a 6 in ruler. Put the first ruler on fabric edge measuring in 2 inches. Then butt the secon ruler against it to cut by. Or if you have your straight edge of fabric on the right side, measure from there with one ruler. Now place a second ruler against it. Remove the 1st and cut with the second. I would do this if I laid the fabric the wrong direction for my cutting(left/right handed) Or if my longest ruler I want to cut by is not wide enough to measure by.

Let me try to explain my method using two rulers. I butt two long rulers
together (same brand to avoid confusion). I align them on the fold of the
fabric with the bulk to my left. When everything looks straight I make
my first cut by holding the ruler to the right. Remove the piece with the
raw edge that I've trimmed. Now I start cutting my strips. One ruler
stays on the fabric (to the left) and the other ruler moves to the width
of the strip I want to cut. Align both rulers on the fold. Remove ruler
on the right while holding on to the ruler on the left and cut. Hold on
to that ruler until you are sure you've made a complete cut. Make sure
that your rulers have enough grip otherwise it will slide. I use the
Slidelock ruler because I don't have enough strength to hold on to
those long rulers most of the time. I put clear Nexcare tape under
my rulers so they don't slide.
Hope it's clear as mud. ;-)

I also start with two rulers to square up the fabric. I lay a ruler line on edge of fold. Then I butt my cutting ruler next to first ruler, remove first ruler and make my cut. Before each cut I make sure cutting ruler has an even line on the fold. If not I repeat for first cut. This works for me and out of habit it is second nature to me.

This is the method I use, but I came to it because I am right handed and use it to get the cut line on the correct side for me to cut it.
Mike

Don't give up trying to use two rulers. It works for me. I use the first ruler to set the second ruler. Then hold my breath as I remove the first one so as not to move it.

Thank you everyone for the good explanations. I saved them all. When it's not so early in the morning and my brain wakes up, I will study them all and work out my method.