Sweater Contruction - Bottoms up!
Why Bottom Up?
The question should be why not?
Bottom up is just as easy as top down. Working a seamless (or mostly seamless) bottom up sweater is only a little different than top down.
For a seamless top down, you work until you need to split the top part of the sweater into sleeves and a body. You cast on a few stitches under the arms and then work the body and sleeves to the bottom.
For a bottom up, you work the body and sleeves seperately (hooray for no sleeve island!), join them all together are the underarm, and finish at the top.
Since sometimes it is hard to picture the joining process, I've created a small tutorial below.
How to join a bottom up sweater
For a bottom up, you work the sleeves and body seperately and then you join them to work the top portion. When it is time to join, start by laying out the pieces out so you can visualize how they are joined.
Mark the join locations
When joining a bottom up sweater, I like to mark where the joins will be. The stitches in the under arm will not be worked and will be sewn closed later. The diagram shows stitch markers used to mark the the unworked stitches.
Start on the body
The join row begins where your last body row ended. This location may vary based on if it is a cardigan (shown) or pullover. Work until the first underarm stitch.
Join to the first sleeve
Stop working stitches on the body and join to the first sleeve. Work all the sleeve stitches.
Join back to the body
Leaving the underarm stitches unworked on both the body and sleeve, join back to the body and work all the stitches until the next underarm.
Join to the second sleeve
The second sleeve is worked just like the first. Join and work around.
Finish the join row
Join back to the body again and finish the row. Work the return pass as indicated. You've now finished the joined row and can work the yoke portion of the sweater.