A few days before I took the machine to MRRF2017 this past weekend I slapped together a rotating drum assembly. I've got a whole two and a half days in the thing. Not surprisingly, I don't like it. Lol.

So far I've mostly made unwoven mats. But for my next trick I'm going to have to get the fibers laid down side by side. There's a reason for that, which I'll go into as soon as the experiment is done.

The reason I don't like it is two fold: it's too fast, and it heats up too much. A side drawback, less serious, is it's not exactly quiet.

The motor and speed control are from an old cordless drill I took apart a while ago for a reason I don't remember. But hey, it's laying on the shelf and works, right? So I gave it a go. I modified the machine a bit to leave me a plug inside of the chamber, and a tossed together case for the speed control plugs into the back of the machine. So far so good.

But when I used it during a run even at the lowest consistent speed it was just too fast. It made it's own little wind storm over it's surface that flung fibers everywhere. Not good. Not good at all.

Add to that that both the motor and the controlled got pretty hot. That changed the conditions inside the chamber and made getting consistent sized fibers challenging. I had to keep adjusting things as the run went on. Since one of the main reasons to build a dedicated machine for electrospinning and not just using a cardboard box or something like that is to make things consistent, this thing just wasn't going to cut it.

To get it up and running before MRRF weekend I just used a spring inside that fastened onto the center shaft, which doesn't turn, and the inside surface of the drum, which does. That gave me my conductive path for the negative side of the hV. Which works. But it makes it loud to run. The day before the show I changed it over to a smaller spring inside of a 3D printed mount. The spring pushes on a metal ball bearing, which of course rides on the inside of the drum.

Still too loud.

So this thing will get redone in the near future. The basic idea is good, but I need to take a look at what motor I want to use for it that doesn't get so darn hot and runs too fast. A stepper might do the job, and would give me fine control over speed. But so might a geared DC motor, too. I have to admit having the motor speed under software control in enticing, so I'll tuck that into the final decision. One of the entire reasons for building this thing is to get consistent results run after run, so having the speed software controlled would be a plus.

If I decide to go with software control I need to consider the electronics, too. Only so many steppers can be hooked up to the board, so it might mean I need to switch that out. But a DC motor speed controller would be needed if I go that route, and while not all that expensive, they don't exactly give them away, either.

Either way I need to get it done. One of the things I intend to do here shortly will need this running right. If what I have in mind goes right I think you'll be impressed, even to the point of trying to find another way to get the same results without an electrospinner. I don't think you'll be able to find such a way, but it'll be interesting to see what ideas you throw out there.