Forget the long arm Hpiner, there is a solution. The term quilt as you go actually relates to two different techniques. I'm going to tell you about the technique I use for the biggies.I too cannot manage anything more than a twin size quilt.
This method that I'm going to describe, uses small thin sashings that join each block together. So if you don't want sashings on you quilt top, perhaps this technique is not for you. So you basically make your blocks as usual. Then cut a backing fabric and batting about 2 inches larger than you block. Pin the three layers or sandwiches together. You will need to do this with two blocks to start with. Now, quilt these two blocks as you like, in your chosen quilt pattern. I'm currently making a large quilt for a boy called Jake, and I've chosen a star pattern that makes up into 18 inch blocks. I've made each block, backed and batted it and quilted the design onto each block.
So here's the joining technique. These instructions will join two blocks together. Cut a sashing strip 1 inch wide times the length of your block, for the front of the block, and
one and a quarter inch wide strip times the length of your block for the back of your block.
Firstly, sew the strip to the front AT THE SAME TIME sew the strip to the back (right sides together) using a quarter inch seam. Secondly, iron the thinner strip upwards, don't worry about the back one yet.
Thirdly, put the second block onto the strip you've just ironed upwards, right sides together and stich a quarter inch seam.
Fourthly, iron the strip that joins the two blocks. Turn the blocks over and with your iron, turn a quarter inch seam on the larger strip. Now you can hand stitch the larger strip down.
Repeat this method with how many blocks you need for a row. Then join the rows as before (only with longer strips), and then join the whole caboodle together.
No more sore shoulders - happy quilting.
Any questions? Fire away!!
cheerio for now