Just one short day after figuring out the Y-axis, the X and Z are both moving!

I decided to stop by Radio Shack and pickup some DB9 connectors (1 male, 3 females) to make switching between motors easier. Although soldering all those pins on (24 total) wasn't much fun, it was totally worth it. In addition to making it easier switching between X,Y,andZ, the connectors also cleaned up a lot of the wiring.

I also soldered headers onto the easy driver so I could actually mount it on the breadboard instead of just setting it there! Worked like a charm.

As for the power supply, i switched from the ATX PS which was pushing 12v, to an old Dell Inspiron 20V 90W power supply. I'm not certain on this, but I'm pretty sure the extra power has really added to how smooth the motors run. I'm not even sure if that's possible, but it seems like it to me.

Here are some video of the other two axis' running. The Z looks especially smooth, which i'll say is from the fact that the acme rod is short which pretty much eliminates the chance of it being bent (as I suspect is the case on the Y axis). The X axis is coming along but there seems to be some friction somewhere along the path which is causing it to hang up and stall the motor (even with the ramp up / ramp down code)

I ordered two more Easy Drivers from Sparkfun yesterday, they should be here early next week. At which time I'll try hacking together something that runs all 3 axis in an indefinite "test" pattern.

Pretty exciting stuff here!

The Sparkfun forum guys really helped me out. After getting the Y-axis stepper up and running with the Arduino, there were some issues. Mostly it was loosing steps in a bad way. Plus, the vibration threatened to tear my machine apart! OK, that last bit was an exaggeration, but the vibration was pretty bad.

The guys on the forum pointed out that you cant just start a stepper at full speed, you have to "ramp up". Which after thinking about it, makes perfect sense. At this point in time, i've learned enough to know that in most cases, "it's already been done". Meaning, there was no need for me to write new code to "ramp up" the arduino. I mean, there are tons and tons and tons of stepper based arduino projects on the web, surely someone must have written some good code.....

The short answer: Yes, it's out there . But, the really surprising part is, that link is the only one i found where the steppers were "ramped up". Now, don't get me wrong, it WORKED! Check the video for proof of that. The difference with a smooth start is night and day compared to just the standard method. BTW: the standard method is: Start a loop, Pull step pin HIGH, put step pin back to LOW, delay for a set amount of time, loop. Most people just set the delay to something that won't stall their motor. This varies greatly depending on the specs, but for the most part people are between 200 and 400ms. I guess I'm wondering why more people don't start smooth? maybe it's just easier to set the delay and forget it... who knows. Either way, I'm really happy with the progress so far. Things are starting to come along.

The guys in the Sparkfun forum are really helping me get this thing going! Right now I'm working one axis at a time. Here is my attempt to move the Y-Axis with a 60oz/in stepper and the EasyDriver from Sparkfun.

If you have a listen, it starts out pretty well and then makes this terrible grinding/vibrating noise. I found out that is the motor stalling and/or loosing steps, It's could be from a variety of things, all of which sound pretty managable. I'll try to get it smoother and more consistent.

Although it's not perfect, I'm fully confident this solution is going to work.

Have a look at the mill page for a peak at my first schematic! I posted a question yesterday to the sparkfun project forum asking how to connect an 8 wire stepper motor to their Easy Driver stepper motor controller. After a few hours and some really helpful replies, I had my answer!

I wanted to try it last night, but ran out of time. Hopefully I can test it out tonight and report back tomorrow on two things:
1.) If it works!
2.) If the motor is strong enough to move the Z axis :)

Thanks again to the guys in the forum for their help!

Also, I used a program called "Project Draw" from the Autodesk Labs website to draw the schematic. Although I'm more comfortable drawing things in Illustrator, Project Draw works really well. I'm by no means a professional electrical schematic drawer, so I can't attest to how great it is at that, but as far as an easy cloud based way to make a line drawing. It works just fine and has plenty of built in symbols to use. So check it out if you get a minute, you might find it useful as well.

There is a point in every project’s build cycle that puts you face to face with the details you have procrastinated. This is the time that you need to focus, keep scope, budget, and timeframe in mind, and make some tough decisions. For me, this time came over the weekend.

From the time I received the first nest from Ponoko, I started thinking about points of failure and then possible design changes. I plugged away, carefully assembling what I could without fully committing myself. In retrospect, I was just buying time I think, time to convince myself that I should change the design, that I should fix some inconsequential mistakes, that I should start over.

Then I glued the main box together, it scared the crap out of me clamping the pieces together and waiting for it to dry. One thing i really liked about the designed made from steel was the fact that you can unbolt them! With glue... well it's sort of permanent. Everything worked out just fine. So I glued the uprights in place, then I glued the cross supports in place. Then there was only one item left to glue, and I glued it.

Now I'm on to the hard part: The electronics. It's so frustrating/exciting to dive into something you know so little about, it's difficult to know where to start. However, working through the reference material I'm reminded of why I like projects so much: Learning!

I was just browsing through my Google Reader page and caught an interesting headline that read "New Hackerspace in Chicagoland: Workshop 88". Exactly what I've been looking for! Looks like to first meeting is scheduled for Monday. At my wife's Alma mater non the less!

I can tell already, this is going to be great!