When I first acquired my loom that has a sectional beam, I looked in the books I had, and then on the internet (searching "how do I warp my sectional beam") to find information on how to use it, and found that what is out there is a little short. From what I was able to dig up, I've worked out my way of warping my sectional-beam loom. So I thought I'd post here how I do it at least, with the thought it may help someone searching as I was.
My sectional beam has 1-inch sections, and the project I am making is 24 ends per inch. So I need 24 packages. In my case, I am winding 24 of the cardboard spools in the photo.
The yarn I bought came on a cone, which I have sitting on the floor. The yarn goes through a stick with holes drilled in it - the tension helps my yardage counter work better. Then it goes through the counter and onto the spool which is fitted onto a bobbinwinder.
My sectional beam is 3/4 of a yard per turn, and I will be putting 3 turns worth of warp onto each section, 3 x 0.75 = 2.25 yards. Adding 2 tenths of a yard for a knot and some overlap gives 2.45 yards per section. I will be using 40 sections (since I want my project to be 40 inches wide in the reed), so I need to measure 2.45 x 40 = 98 yards onto each spool. If you are used to doing the calculations for a standard beam, the math logic may seem kind of "sideways" until you get used to it.
I guess "yardage counter" is a bit of a misnomer since my counter actually counts feet and not yards. Sigh. 98 feet x 3 ft/yd = 294 feet. So I'm running the counter up to 300 feet "for good measure", as they say.
If you just buy a bunch of tubes or cones, then you could skip this whole step. I don't buy yarn in anywhere near that kind of quantity, so I divide it up as I need it for each project.
Next installment, winding onto the beam, where you'll see my jury-rigged tension box and an alternative application for aquarium tubing. Stay tuned...