Just a thought for larger quilts - longarm quilters will sandwich and baste a quilt for you and it isn't as expensive as them quilting the whole thing. Maybe $40 for a queen size quilt? I don't know if hand thread basting is weaker but do know that machine thread basting will definitely hold up to machine quilting. Definitely consider basting with the washable school glue as it is easier and much lighter then pin basting.
Glad to hear of your frame that will save your back. I too have back problems and have to think ahead all the time to help keep injury away.

I often do my sandwiches in part that aren't so big and easier to handle and doesn't bother my back. I also fmq the parts as they are easier to handle in the machine as well. Then just stitch the parts together. Sort of a quilt as you go techinque.

Oh do consider Elmer's glue basting if you can incorporate it into your frame method. I'm still able to tape my backing to the floor, but DGD was a big help this last time:).

I've only done the glue baste with a small baby blanket but it seemed to work well. I need to get the courage to try again with a larger project.

I put my backing on my cutting table, center it, clip it to the table with Office Clips, the largest ones, then the batting, move some of the clips to the batting, then center the top to all of it, re-clip every thing, then pin it all. when it is pinned, un-clip, adjust the quit, re-clip, pin, move again, etc. I can walk all around the table with out killing my back.

I, too, have found that the board method is a life (and back) saver. I covered my boards with decorator cotton and they are very easy to use to roll the quilt top and the backing. I roll the batting around a core of PVC piping.

I use a bed to lay the top on, then batting, then backing. I spray baste large quilts and let them air dry before moving them. Often use a few pins too, so I'm not bent over all that much.

When the day comes that I can't bend over the bed anymore, I may take my quilts to the church hall and put two or three long tables together and sandwich that way, standing up.

The way to go!! Inexpensive (buy it by the gallon and refill smaller bottles), no shifting of fabric, washable, no complicate directions.

Get me to the longarmer!

Where there is a will there is a way! lol I'm so glad you found a way that works for you because giving up quilting is not an option! All of us have to find a way to do things that works best for us & our situation. This board is always so much help with input on how they do certain things to make the process easier. So many creative minds here.