if it's a string quilt- why not just go ahead & finish the blocks with the 1/4" foot you like better- then trim the first blocks to be the same size as the new ones? or finish up without making changes & remember the new foot for future projects. when i do string quilts i usually need to square up/trim blocks anyway to get them all the same- there is always a little variation as i go along- especially when so many blocks are involved- so i would just trim them all the same size before starting construction- but that's just me...i would never consider taking 100 blocks apart---i may decide to use them for a different project---but i would never take them apart
