The posts about ripping fabric have been interesting so I decided to rip some for borders. Will never do that again.
While my ripping was accurate in width, ripping stretched the edges of the fabric and even tho I measured carefully to make sure the side pieces and the end pieces were same length, there is some waving at the seam line now that the border has been attached. I ripped because of the length of the border and I didn't want to take the time to cut with the ruler.
Nest time, if I rip to make the fabric more managable, i will rip a piece wider than needed and then cut down with the rotary cutter.

I rip sometimes but when I do I starch because my edges ravel and I haven't had a problem with wavy edges.

Oh no! Did I start that trouble for you? :(

I have seen ripping on shows - but they always trim after.

You always have to rip wider than what you really want and then trim it down. Sometimes I rip sometimes I cut it just depends on my mood. NEVER, ever, measure to the correct size and rip to that. Sorry you didn't know that first. I hate it when I try something new and it doesn't turn out right. It is, however easier to rip a long piece close to what you need then fold and trim. You'll get the hang of it next time.

I rip all long borders. First I rip about 1/2" strip to be sure it's straight of grain. I press the ripped border flat but don't retrim. That is defeating my purpose to rip in the first place.

I ripped for the width and then measured and cut to length.
However, as they say "it will quilt out".......right?

I haven't ever ripped fabric so can't comment on technique with that but I can say that some mild border wave will "quilt out" if you quilt fairly heavily in the border. I had a top that I attached borders incorrectly on and I had a ton of wave. I HATE redoing anything so I left it and prayed it would straighten out a little with quilting. I did a medium-small stipple all in the border area and was amazed at how much wave was taken out.

Hope that helps the problem this time! I personally don't care to try ripping because if I have to trim it up afterwards, I might as well have just cut in the first place. :)

Ditto. Sorry you are having a problem.

I have ripped my borders and backs for 27 years and have never had a problem. I always rip the exact size and never trim. I press after I rip no waves or distortion.

Once a ripper always a ripper. LOL