All great advise, Keep at it it will get better. I just hate it when this happens and if you are like me good enought is hard to swallow!

Are you using the same tool for measuring throughout the process? Something the measurments on the cutting mat are slightly off from the measurements on the ruler. If you use both, you might try using just one or the other.

For accurate 4 patches without triming
 

I just finished making 42--16 patches that did not need trimming. I find that the extra time I spend in making sure my cutting and stitching are accurate, saves time in the long run.
1. Starch fabric
2. Press on the length of grain (parallel with the salvage) tip from Ami Sims.
3. Use June Taylor shape cutter to cut strips. This assures accuracy.
4. Cut strips on the length of grain. Decreases distortion. (Marti Michell)
5. Layer two strips right sides together and cut into sq.
6. Pin sqs together. Will save time matching up when you sew.
7. Make sure that two squares stitched and pressed, give you the proper measurement.
8. Chain piece sqs. Finger press do not use iron. saves time less distortion.
9. Nest seams and stitch four patches. No need to pin, (practice will make perfect)
10. Finger press. Open seam and press so you see the little four patch on the back. (Kaye Wood)
11. Press with iron from back and then front.
12. You should have an accurate four patch that does not need to be trimmed.

Donna Slater of The Feathered Nest has a great tutorial on her facebook page or go to her blog quiltsforthenest.blogspot.com Her directions are based on the Billy Lauder method. She co-authored a book on Sudoko quilting with Billie and Billie gave her permission to publish the technique.

Great tips. I need all the help I can get. My points don't always match up. I saw a great technique from Kimberly Einmo on craftsy and did everything exactly as she did, but my points still got messed up a lot. I agree with the poster who wrote "good enough is hard to take"

Cut the pieces bigger than required, and then you can cut them down to whatever size you want for your quilt.

I've ALWAYS had problems matching seams till I found these fork pins -- Boy, what a difference!
http://www.joann.com/fork-pins-35-pkg/9620840.html

Your problem is clearly in your seam allowances. They're off. What I use is the small ruler below. It's called a "Perfect Piecing Seam Guide," and it measures exactly a scant quarter inch from the center of the needle. All I have to do is (carefully) insert my sewing machine needle into the tiny hole in the center of the ruler, make sure it's straight (I have used a 45 degree angle ruler to make sure, but then, I'm a bit on the Obsessive-Compulsive side) It's hard to get the ruler crooked. Put down your presser foot to hold the ruler in place, and do something to mark the edge. I like to use a self-cut strip of moleskin or heel savers. Then don't forget to check your seams. I use scraps to cut 2" strips, and I cut 3 strips. That's 6 inches, correct? But if you sew together all three strips, that's 2 seams at 1/2" total each, or in other words, you final block should measure exactly 5 inches. Your center strips should be exactly 1 1/2". So if it's not absolutely perfect, adjust your seam guide again. I love when it's perfect because everything matches up.

The scant 1/4" seam guide does NOT give you a scant 1/4" seam. It gives you a perfect 1/4" seam because it allows you to account for the bend in the fabric over the seam. I've discovered that with thick material that needs to bend, I have to make the seam allowance a tiny bit smaller because it uses more fabric to bend over the seam. Anyway, this ruler and checking the seams before I start each project, because the fabric itself can alter the seam allowance a tiny bit. If that's the case, I'll find out when I do my test.

https://www.etsy.com/listing/111397285/perfect-piecing-seam-guide-14-inch-ruler?utm_source=google&utm_medium=product_listing _promoted&utm_campaign=supplies_low&gclid=CNPv5rf1 ursCFdJcfgodrEkAtQ

I hope this helps, and is clearer than mud!

I have gotten to where I would rather start bigger and cut back - even though it takes longer, it saves a lot of headaches and wasted (bad) outcomes. :-)

Marysewfun

One thing that I found out is that not all measurers are the same. It seems like one brand is one way and another is the other way. I have found that 4 patch or what ever size comes out different but have learned use one measuring strip for all.