New Quilter Needs Help
 

This is probably a dumb question but can you use a 1/2" seam allowance on some of the blocks in a quilt and 1/4" on the rest of the quilt without messing everything up? I have never made a quilt and I'm trying to follow a pattern.

I'm using 5" charm squares for most of the quilt but the pattern also requires that some of the 5" charm squares be subcut into four 2" squares. These subcut pieces are then sewn together into a 9 patch that is supposed to come out the same size as the 5" charm square. I used a Sizzix die to subcut the squares but realized the die if for 2 1/2" "unfinished" squares -- not 2". Instead of having to cut all of these little squares down into 2", I wondered if I could just use a 1/2" seam allowance on these blocks. Hope I have made sense in what I'm saying.

I would try a block with some scrap fabric and find the seam allowance that works to get the size block I need. People adjust their seam allowance often to achieve the size blocks they need.
Welcome and enjoy the process.

Thank you. I think I am just afraid of making a mistake after spending so much money on this pre-cut fabric. I think I need to relax a little:eek:!!

This is my thinking. Three unfinished 2 1/2” squares lengthwise x three unfinished squares widthwise will equal 7 1/2” unfinished square. You will have 2 seams in the center both lengthwise and widthwise so if you make the seams 1/2”, you will have 2” less when the center part is joined. The 5 1/2” square will not butt up to the 5” square. Do you have a rotary cutter, mat and template? Sorry, but I’d recut the small squares. Welcome to the board. You will learn so much here.

I agree wit ckcowl - try it on scrap pieced first. The other thing you could do - is sew the 1/2" seam and before pressing it trim it slightly to cut down the bulk.

Why not just take them apart and recut the 2 1/2"?

Maureen is right. If you make a 9-patch from the 2.5" squares, using a 1/2" seam, it will measure 5.5" unfinished. When joining the charm to a 9-patch you would have to align the pieces so that you have a 1/2" seam allowance on the 9-patch and a 1/4" seam allowance on the charm. It could be done, but it would be difficult and confusing. Can you get another 2" die to make cutting the 2.5" pieces down a little easier?

Welcome to quilting! That being said, I would add that sometimes (almost always!) it pays to back up-rip stitching out- and do things as directed for best results. Making 1/2 seams creates all kinds of difficulties as the process goes forward. As mentioned by several others, the proposed solution will not work. We all have to back up from time to time. It is just part of the process. Please know that we have all been there; fixed the problem; and, moved forward to happy success. My bit of advice is to fix your problem before you put your project away rather than have to come back to a project that has to be fixed before going forward. I still love new challenges after 50 years of sewing and quilting.

I would also recut them into 2 inch squares -

I have attached a drawing that might help explain what would happen if you used the 2.5 inch squares with 0.5 inch seam allowances.

Or use graph paper and save your scraps!