Well, after a lot of work, and a lot of frustration (which comes from learning tons of new stuff (actually a good thing once you get through it ;0) ), I have the Shapeoko cutting. The bolt is meandering so to speak.This is the Hello World for cutting. The wiki suggested doing an initial, I chose to do my full name so I had something to put on my desk at work. Also, it suggested doing a pocket cut of the initial. Probably bad form for jumping out of the crib too fast, but I wanted to try pocketed Island cut. I used the NASA lettering as my guide. While this is great for some letters, I am not too keen on the K, but I can not blame the machine for that. I only blame the font. Anyhoo, This is the first cut off my Shapeoko. I am more than pleased. It was an odd experience. While it was running was watching with amazement at how precise it was. But the most common phrases while watching the cut were “but what about the..” , or “but there’s still a…” and then “Oh… I see”. Now I can focus on just making stuff. High on the priority list is cutting out my own upgrades. You know build a machine to build a machine.
So, here is the the video of my first cut. I know I know… yet another first cut video, but hey, I am a proud new parent, so I wanna hoot and holler for a while. 😀
I faded out the audio so you didn’t have to hear the whine the whole time.
I have not done much more to the machine itself as I have been fighting the work flow. I have been trying various things for about 3 or 4 weeks, but I have basically stopped down to get a handle on it as this is a kind of important bit of the puzzle. I have been trying to find a tool chain that is as close to free as possible (The Shapeoko was an expensive bit of kit)(relatively speaking).
Many people jump into InkScape and start going. Being a software snob (something I need to get over. I get it). Like most things, I do not want a surface understanding about what is going on, I want to grok with a fullness. I don’t remember how, but I accidentally found Draftsight. I have spent a lot of time trying to come up to speed on it. The idea was Draftsight for design into MakerCam for Cam and G-Code production then mill. The problem I had was that everything I was designing was initially getting scaled up by 6 and a half times. I finally found out that upon install Draftsight defaults to imperial even though I had specified millimeters (something not mentioned in any of their tutorials btw). I found that I could change the default to an ISO template so numbers started to make more sense. I exported an svg on my design and took this into MakerCam. Things then started to get stupid again. This is the cam software that the Shapeoko people recommend to get yourself going. Perhaps this is just fine if you are going to InkScape then to MakerCam, but I have not had it work all the way through without something going really wrong (from weird numbers, crazy decimals, crashes when zooming, no undos…). So, I have decided to stay as far away from it as possible. Free is not worth that much frustration
I then downloaded FreeMill (a free little cam app that comes with Visual CadCam 2014) and started to fight with that as it has been said to be a pretty good CAM app. I tried and tried and tried to get it to see my drawings as a “part”. The short story here is that it does not do 2.5D, only 3D. So, I am keeping that in my back pocket for when I need 3D. So onwards…
This week I decided that my time was more valuable, so I ditched the idea of not trying any of the paid software options. If it will do the job, and I save a year not having to fight all the little work arounds, then I am all for it. I downloaded CamBam. It is a $150 CAM program that has a LOT of really nice features in it (scope is coming from MakerCam). I get 40 uses fully featured before it clamps down to 500 lines of G-Code. A use is considered starting/closing the program. So, I have had it open for a couple of days. I will eventually need to throw down some money, so be it as long as it works and works well. The nice thing is that it is geared toward a range of people types, so it will do, 2D, 2.5D, 3D, engraving, and most recently added PCB. PCBs are one of the reasons I wanted the mill, so at $150 is not a bad price (especially seeing what some cams can cost). Snow days are great for getting all sorts of things done. My target is one of my left over Pinewood Derby blocks. It is essentially the mill version of Hello world. They recommend that you cut out the initial of your first name. I chose to make a pocketed Island of my whole name with a little square around it. I just have to get up the balls to actually go do it. Seeing how this thing has just taken off for reasons I do not yet understand, frightens me. The idea of a robot running off with a very fast moving cutting device attached to it…myeah. The sucker is strong too. When it wants to go somewhere I am not going to be stopping it. Only a reset, or cutting the power will do it. I have a mushroom safety switch that I will be wiring into this eventually for such a thing.
After the wires were made, I connected all the motors in a not so pretty fashion. I hooked up the Arduino and GRBL Shield and tied in the stepper leads. I opened up the Universal G-Code Sender and tested my motors. Everything seems to be working. I spent a bit of time trying to read about G-Code, but it reads like stereo instructions. It is important to know, but not something you can just sit down and read and somehow retain. It takes association and I have not had any. So, I read over getting my GRBL shield configured. When everything looked right, I decided it was time to let er rip. Feeling good about how things were going, I attached a sharpie to a wood block which was then attached to the Shapeoko. I started jogging the head over to where I planned to call the world “0”. It does not move very fast as each click on an axis equals 1 mm of travel. So, I decided I did not want to wait forever, so I tried 20 mm per click. This worked much better as I could click the buttons a few times and scoot it to where I wanted it to start fairly quickly. The Z was too high, so I pressed the Z- button a few times as I had done with the X and Y.
This was a mistake. The Z axis (up and down of the head) only needed to go perhaps 25 mm. The brain starts to work amazingly quickly in a moment of perceived emergency. I sat there in awe, amazement, horror as I watched the Shapeoko lower my sharpie down to the surface. I wanted it to stop, it felt it should keep going. You know the saying “garbage in garbage out”, well the result of my garbage out consisted of watching the beautiful sharp point of the sharpie squish itself flat and up into the pen. But it did not stop there, oh no. 3 clicks? I had essentially told it to lower 60 mm. It then occurred to me that I had not read anywhere in the instructions about what to do if/when the system goes silly on you. Not sure what to do, I grabbed the end of the sharpie and pulled it sideways so it would not damage the work surface, or the gantry head, or or or (I do not know what this thing is capable of, and did not want to find out). I tried pressing cancel in the program, then I realized that this will do no good as the program only sends a command to the controller, it can not make it stop until the current command is finished. My only options left were the Arduino and the controller. Kill the controller, remove what it needs to survive!!! I pulled the power and the chaos stopped. I can not tell you exactly how long all this took, I just know that it was over and done quickly. Note to self…
Having just learned (by the process of natural correction), Z-axis, gets lowered slowly. Small increments. Do not rush. I regained my calm and found another good sharpie and strapped it on. I clicked the send button in the UGS (Universal G-Code Sender program) and the machine took off into the design. Here is learning moment #2. In the chaos of the previous situation, I forgot to reset the zero point. So, the head took off towards the other side of the machine, raising the head back up into the air. There is something hypnotic about watching it move. It is enjoyable and the sound is somewhat dub step in nature. I knew what I had not done and due to the previous event, I knew that I had to pull the power… AGAIN. Grrr.
I got the machine back to where I wanted it to start. New Sharpie was ready and waiting. I took a moment to go through all the various settings and made sure all was well with the world. This is probably a good idea in general. I sent the file and the machine sprang into action. It started drawing the Hello World like a champ. This time I could just sit and watch and enjoy the thing. It was great. I noticed that as it got to the end the pen lost contact with the paper. I could see that the paper was floated a little bit above the surface.
Here is a video of the drawing of the Shapeoko 2 logo. Now, with the back story, you understand where the marker streak towards the middle of the paper came from.
Knowing that I will be putting the electronics into some sort of enclosure, I went ahead and pre-made the wires that will run from the controller to the enclosure front, and from the enclosure to the steppers. Instead of splitting the wiring for the Y axis motors later at a terminal strip, I flipped the black and green (for the second Y stepper) at the connector. I will then have 4 cables coming from the enclosure to the the motors.
