Wow. I haven't had any problems with them since I figured out the flat end needed to lie flat on the ironing table. (Yes, I actually held the thing upside down for awhile.)
One thing I do that I think makes a difference is I heavily starch the fabric before cutting the strips. This helps with loading the tape maker, but also helps with keeping the folds nice and crisp and even. It also helps keep the joining seams in the strips flat. (I join on the diagonal and press those seams open.)
The first few inches are never as good as the rest. What I do is allow about the width of my iron plus an inch or two for getting started. At that point I leave the iron resting on the ironing board. My right hand holds the tape maker and works in tandem with the left hand pulling the strip from under the iron. The tape maker is flat on the ironing board (
) and I just run the strip under the iron maybe 8 inches at a time.
Haven't seen the Youtube videos; I'll have to go watch them and see if they do it the same way.
Edit: Well, I found this Youtube video that is pretty close to what I do:
http://www.youtube.com/watch?feature...SRBnmKrcM&NR=1
I have done it that way too, pulling the tool as I iron. I noticed her strip is on the straight grain. If you are dealing with bias strips, I think starching first really helps keep the fabric from "wiggling" while you work. Also, I cut a point on the beginning of the strip before threading through the tool; at least on the smaller sizes, this helps me a lot to get the strip started.