I've been teaching people to warp a Mirrix and other pipe-like looms with a continuous warp for years now. There are people who immediately understand how it works and don't have a problem with the pattern the warp must follow as you warp. There are other people who struggle with this a lot.
I believe this stems from a particular spatial ability some of us have and some of us don't. (Don't worry, if this isn't your skill, you can still learn to warp a loom. You undoubtedly have many skills the rest of us don't.) I have particularly good spatial abilities. In fact I'd say that my memory is very spatially oriented. I am especially good at remembering places and paths. I hiked the 500-mile Colorado Trail from Denver to Durango in 2003 and can still tell you details about all parts of the trail just by positioning myself there in my memory. When I have re-hiked hundreds of miles of the trail recently, I realized my memory from 2003 was quite accurate. But I most likely can't tell you the plot of a movie or TV show I watched last week and I'll never be able to tell you the name of the actors. I remember books that put me someplace in my imagination and I won't remember much about a book that doesn't--even if I really enjoyed reading it... unless I hold the book in my hands again and can somehow dredge up the sensory experience of the place I was while reading it or can flip through it as an object and see comments I wrote in it.
When it comes to warping, I think this ability to imagine things in space is very helpful. But there are many people who don't have this sort of brain. You know who you are. You can't make sense of any map and rely completely on the British-accented woman on your phone telling you when to turn on the way to the nearest Chipotle in a strange city. You can't picture where Crested Butte is in relation to Steamboat even though you've skied at both of them many times. And you don't have a good idea of how far it is from San Francisco to Seattle (2 hour drive? 4 days?). You may also not have been very successful learning to sew. Turning a flat shape into a three-dimensional garment does require either a slavish commitment to following the pattern directions or a spatial ability to manipulate the shape in your head and see how it will become something wearable.
If that is you, perhaps this diagram will help. This warping pattern is for continuous warps. That means that the warp is formed using a warping bar* and it can be rotated as you weave to provide a larger weaving surface.
This diagram was drawn for me by the illustrator/artist Molly McNeece. It works for Mirrix looms but also for any pipe loom you want to warp this way. On a pipe loom, you may have to lash a longer bar to the loom to do the warping and the replace it with a bar that is narrower than the side supports of the loom before tightening the tension.
Warping pattern for a continuous tapestry warp
Notice that at no point does the warp cross the bar. Every time it comes to the bar, it wraps around it and goes the other direction. Some people find it helpful to think of the warp as a long loop like a skein wrapped around the loom with the bar holding the whole thing together. (If that isn't you, stop thinking about that and ignore the photo below! It takes some ability to manipulate shapes in your head to envision how this works.)
A loop of warp with each end of the loop held together with the warping bar as in continuous warping.
Here are images of a warp on a Mirrix loom. You can see that it wraps around the loom completely and is held together with a warping bar.
I have finished this little piece and am ready to advance the warp to weave something else on the rest of it.
Here you can see I've put in new stretcher strings and started some waste for another piece. The first piece is hidden behind that black piece of cardboard (which makes weaving MUCH easier visually).
The piece has been rotated to the back of the loom. Notice that the warping bar is much higher on the loom now and there is clean warp in front.
Back of the loom showing the advanced piece upside down and the warping bar a little more than halfway up the back.
Does this help clear up the mystery of warping a continuous loom? Do you have difficulties with spatial understanding? If so, what are your other superpowers? Leave a comment below.
*You can also do a continuous warp that does not use a warping bar by tying the warp to itself at the beginning and ending. In this case you have to pull on the weaving instead of the bar to rotate everything. Kathe Todd-Hooker regularly uses her Mirrix and copper pipe looms without a warping bar.