If I change a baby raglan cardigan sweater from stockinette stitch to garter stitch is it going to change the size of the sweater?
Garter stitch is a denser stitch pattern than stockinette so it will take more rows of garter to equal the same length of stockinette stitch rows. Ordinarily this isn’t a problem because we work to a length in inches but it may mean spacing out the raglan shaping a bit. On the other hand, it is a baby sweater so the number of raglan shaping rows at the armholes is probably not very many.
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