I learned from reading here, to put the fuller piece on the bottom and the feeddogs would take up that fullness as they push the fabric thru faster than the foot does. But I find that when I do that, I have "waves" in the fuller piece of fabric that don't seem to press out. It will press flat, but then when I lay it down, there are the waves again.
Any suggestions about what I am doing wrong here, or how I can get rid of the waves? They are very noticable in the photos I posted of my row of the month efforts!

It means you are trying to ease in too much fullness in the bottom layer.

Do you have a link to your post with the photos? If I am remembering the right photo, it looked to me as if your cutting and seam allowances might not be sufficiently accurate. If they aren't, the rows can be insufficiently accurate to be sewn together without ripples.

Starching fabric before cutting can help a lot with accuracy, but I think you got the squares in a swap? Even then, using spray starch to "block" each square to an exact measurement before sewing them together can help.

Also check your sewing machine. Cut two long strips exactly the same length and sew them together. If the ends don't match, the machine may need adjustment and/or you may need to modify how you sew seams to compensate for this.

What size needle are you using? And what brand of thread? Sometimes these can make a difference in rippling of seams too.

If you are using blocks that you received in a swap, measure them to see what size they are.

Actually, measure all blocks to see if they are the expected size.

If one has changed rulers, or presser feet, or sewing machine, or taken a leave from the project, check to see if the "new" blocks are the same size as the "old" blocks.

One can ease a "little" and it will lay flat. After that one has "gathers."

And the smaller the block, the less wiggle room.

I think I have already discovered some of the issues I need to deal with. LOL... as I said, I am a newbie. I don't even know what size needle is in my machine. It's whatever was in there since I used it at the last sewing get-together I had with my SILs. I have 3 different rulers I use to cut my pieces, and I use them interchangably. And yes, they are each a different brand, so that could be a lot of my problem right there. Sometimes I use all 3 when cutting the pieces for one quilt block. I was just reading about that on this forum yesterday. Who knew an inch wasn't always the same on each ruler? There aught to be a law about that!!! Sheesh. LOL. I am getting much better at my cutting, and at making sure my pieces are the right size as I go.
I didn't get any of the blocks in a swap, I made the messes all by myself. LOL.
I am learning so much from all of you. I will make sure that I am more careful about how much slack I am trying to take up with the seam, and I will do the long strip test before I sew any more pieces.
I think that I have been somewhat inaccurate, and relied on my seaming to cover up a lot of things that they are not equipped to hide. There may just be days when I have to say no to doing things that require accuracy and escape to the garden instead. Smilesss and hugggggs

Since you are cutting your own fabric, then you may want to starch before cutting. This helps stabilize the fabric. That, and using one ruler for all cuts, should help a lot.

Definitely change the needle. If you are using regular thread, usually a size 80 needle works well.

If you have a walking foot for your machine, this is a good place to use it :wink:
I didn't see that you said you measured all of the sides of the top before you cut your borders... It isn't always a good idea to just go by the pattern if your piecing changed the size of the top at this point. If you have cut them too long, they will wave. :D:D:D