Not all threads are created equal, I guess

After I disassembled my second prototype I’ve been trying to sew it back: Three times now and every time I ended up in failure by kinks.

Now I think the thread is too thin. Not too long (I jotted down the correct length when I first sewed up the second prototype). Not insufficient waxing (in this last try — after I first noticed the probable cause — I had waxed the thread like six or seven times and it still kinked up). I must have been using a different kind of thread and never noticed the kind of thread made a difference.

So this “30 weight” thread is useless. I have some upholstery nylon thread but they’re the wrong colour. I’m going to need to get some nylon thread of different colour and get some denim thread and some other kinds of thread that’s not “30 weight” and figure out what exactly I was using.