So I bought a sherline 5800 Cnc mill…but I jsut need somewhere to start with the actual use of it. I have a 3D model and a sheet of aluminum I would like to cut the file into. I got the steppers working and hooked up and did some manual cutting with one of my end mills. So my questions are.
How to I generate gcode of the 3D file?
How do I tell the machine where to start?
How do I ensure I don’t go crashing into the build plate?
Proper speed/depth to cut through aluminum?
And for the hardest part how do I easily flip the work over to cut through the other way? (Example beveling both edges)?
Any help would be appreciated. I have worked with 3D printing for years but this has me puzzled and it didn’t help the sherline documentation is aweful.
@Curtis_Cummings I have the Cnc package that sherline provides for control of the machine. I use fashion 360 to model. And I don’t know what to use to generate gcode
I’m not a Fusion 360 guy so give me a little bit and I’ll ask the “guru” I know what his process is, and get back ASAP. Honestly I thought F360 did that as well. So we can both learn something.
@Derek_Schuetz
Tell us a bit more of your environment, WIndows, Mac, Linux?
If you have CamBam or Vcarve, you can import a .stl file, and then play with it to get some gcode generated via tool-paths as a start. You can get a trial of CamBam that will let you try out several sessions, so that might be a good starting spot.
Feeds and speeds depend greatly on the tooling you have, and the capability of the Mill, you’d best look at the Sherline forums to get hold of any charts they might have, thus matching your motor on that specific mill, and your tooling.
You need to be exacting with the depth of your materials and the toolpaths and depths you machine too: for example if you have an bit of aluminum .25 thick, and a small end mill, such as a 4 flute flat end mill, you would set it up to ease into the cut, and take several loops of say .0625 cuts to get to the full .25 inch depth. Then you won’t dive into the main bed.
You might want to start with some simple items to begin with before you try to convert an .stl file into a gcode file; say a circle, or a square cube to get used to the machine. You might find some simple items in the Sherline forums to tinker with, but feel free to email me and I can get you some sample code.
One thing I did to get started was to put a piece of MDF under my aluminum plate when I was starting out. That gave me a cushion in case my numbers/depths/cuts were off.
@Bruce_Lunde I’m trying to find sherline forums bit have no luck. I guess the thing I’m trying hardest to wrap my mind around is positioning the piece prior to starting the job. 3D printing has end stops so it’s easy. Do I just move the head to the edge of the material right against it or do I offset it? How do I know it’s in a good place to start?
@Derek_Schuetz We set a zero point, whether it is the center of the work piece, or one of the four corners, then generate the code to work from that point. So let's say you have a 4 inch piece of stock, and you are cutting a 3" cube, you set the start point at the center; and you put the hold downs at the outer edge to keep them from being cut up! The gcode will ensure that you do not cut outside the proper area, based on the starting spot.
@Derek_Schuetz basically, yes. So you set the X,y as 0,0 position, and the top of the material is z0. Then everything else is calculated for you. So, it does not matter if you are using a mill or a CNC router, you start this same way. Take a look at this YouTube, not trying to push this product, but this tutorial will be similar with any cad/cam solution. Once you generate the gcode, you have to tell the software that will execute the gcode the same starting point. For example, I use VECTRIC Vcarve to generate my code, then I use mach3 to operate my mini-mill, I set X,y,and z zero point s
Just like in Vcarve when I was designing. Do watch this to get the basics. https://youtu.be/VU8ufrHqDs8
@Derek_Schuetz Once you watch that, you’ll hopefully have an idea of the beginning; quite a lot to learn, but since you have worked with 3D printing, you will know inherently that there are no perfect tool sets! Each group of users have their own way of getting started. To generate a dxf, you can use many tools too, part of the fun, part of the pain.
Sketch up, fusion360, Etc. to generate the dxf design file, then a tool to create tool paths from the dxf, then finally the program to send the gcode to your mill. Very similar to a design tool to create the .stl file, then using a slicer to create the gcode, and finally sending that code out to your 3D printer.
In fusion 360 you need to get into the cam environment, and make a setup which defines the origin and model and stock. Then chose a machining strategy once you get it right you do post process and it will generate the gcode. It’s not limited or anything like that it can do very well. There’s lots of videos and tutorials on the net for 360. NYC cnc does some really good ones. As to flipping work you need some to reset the zero on the piece after flipping, using a probe, edge finder or some sort of jig. There’s many different ways to do it.
@Paul_Shaw so I got a path generated. Can’t find what to change to fix the depth per pass. I’m assuming thats plunge. But when I go to post processing there is so many choices and I can’t figure out which one will spit out a gcode my machine can read
There’s tabs along the top look through them, depth per pass or something like that what are you doing a profile or adaptive or something else? You need to chose your machine in the post processor. You can run a simulation in 360 too so you can see the depth, speed and order etc. Also it’s a good idea to run what we call an air job for your first cut, set the z zero so it’s well above the work, and even at the lowest point in the code it can’t touch anything then run the code and see what happens, hopefully it moves the way you expect.