Still very new to this and learning. I still have not gotten anything useful out og the snapmaker - now trying to use the CNC first broke a bit trying to adjust work origin and this is the result of running boundary - something is not level - what can have gone wrong? And what can I do to fix it?
Run boundary is a test to determine if anything is in the path of the endmill bit. I would suggest that you do not run boundary just above or right next to the workpiece. Set the height (by jogging the tool) some 20mm clear of your workpiece plus make sure your jog height has accounted for the clamps in use. That way the run boundary command will not push the tool bit into anything while the command is running your machine. The command will let you see in a practical manner where any potential obstructions are going to foul the tool bit at any point in your toolpaths that are a part of the job you wish to accomplish.
I do it somewhat differently and have no need to run boundaries in CNC work. I created some clamps and a table that uses them so that the height of the tool bit when it is moving without cutting, cannot foul the clamp height. I also made the clamps so that the clamping area could not be fouled by the tool bit. My clamps do not intrude on the workpiece more than 5mm and do not extend more than 5mm above the work piece.
Providing the tool path (center of the cutting path) is placed at least 6mm from the edge of the workpiece and the jog height is also set at 6mm, there is no possibility of the tool bit hitting a clamp. The other important factor to consider is tool bit diameter. A 3mm diameter tool bit needs a minimum of half of its diameter added to that 5mm clamp intrusion space to keep it a safe distance from the clamp. The smaller the bit diameter, the less safe distance there is so for a 3mm tool bit I add the complete diameter and a toolpath of 8mm will keep the bit far enough away from the clamp for safety.
In practice, I know that a 10mm tool path from the edge of the workpiece of any shape, will get me a safe path for the 3mm tool bit (maximum permitted on SM1) and I have no need to run a boundary. A couple of links which may assist you. (warning - there is a lot to read)
My clamp and bed system to illustrate what I have said here.
It is worth noting that CNC engineers spend a whole career learning how to accomplish the tasks they set the machines. There are a huge number of online resources but as always, at the start of any unknown journey, we do not know what it is that we must learn about. Here is a link to a useful blog that will have many articles of interest to beginners. Pick the ones you read initially and try a few general articles too. It will light the way almost without you realising it.
YouTube provides a lot of information too and you will have more than enough video presentations from which to select and watch.
For levelling the bed there are many techniques that can be used and these will frequently be machine specific but the principles will be the same across all machines. For example, if you were to put a spirit level on the bed as it is, do you know if there is any variation as you slide the spirit level from front to back or from side to side? That simple test may show you that the framework of your machine is in need of reassembly or placing on a flat and solid surface as you assemble the machine in its final position and do not move it afterwards.
The amount of cant in the spindle can also create issues if the spindle is not truly perpendicular to the bed from front to back or from side to side. There are simple techniques for straightening a canted spindle. At this point you may decide that you want (need?) to invest in a dial gauge so that you can measure these deviations accurately. The spindle may exhibit side to side deviations as it is running and this phenomenon is known as runout and can, to some extent, be cured with a dial gauge and judicious use of assembly and tightening techniques that negate sloppy manufacturing tolerances.
One quick and dirty method is to create a new wasteboard that accounts for all of the machine’s inaccuracies and has an appearance of being flat and level. So long as the machine inaccuracies do not alter, it will serve you well for wood working. Selecting the correct tool bit for the material and feeding it at the correct speed will help avoid tool bit chatter and subjecting the machine to stresses that will cause it to move out of true alignment.
The (tool)path is long and very interesting and it it will delight and frustrate you in equal measure during the coming years. There is great satisfaction to be derived from planning a project, designing it, transferring it to a machine and have the machine do exactly what you asked. Have fun with it and enjoy your successes. Laugh as you throw the failures into the trash but learn from them. Always ask yourself how your work is visiting the trash can again.
A some useful articles on end mill bits and feeding tool bits into work.
https://www.cutter-shop.com/information/chip-load-chart.html
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If you have only run a boundary, the error here is to run it when the tool is on the workpiece. The table is not level. Try a spirit level to see what the error is at all part so the table and see if you can detect which portion of the table is out of true. The bed itself maybe responsible if that is out of true.
What is normal is that every type of machine tool has to be set up to be in true alignment otherwise the work cannot be relied upon to be true.
Thank you for your very informative reply!, I can see there is a lot more to this than just reading the manual! So I will have to read a lot up on this i guess.
But from my poor results so far, I am pretty sure there must be something that is assembled wrong, since both 3D print, Laser and CNC seems to be off at some point.
You are welcome. The manual is barely adequate in that it only really explains how to get things running. It is not within its scope to explain how to true up the alignment of every parameter than can cause out of true errors. In simple terms, if you placed the wasteboard at an angle of 1 degree, you would never be able to rely on any machined workpiece being truly flat. It would be perfectly flat and smoothly finished but never perpendicular to the mill bit.
What makes the issue a little harder to deal with in one sense is that with the advent of digital everything, we now want to see the numbers correct. This is a near impossible task because of all of the imperfections in the workpiece, and the machinery techniques. We used to use the mark one eyeball and a few simple measuring tools that permitted a little variation, now the digital revolution wants to run just the numbers.
Try not to dwell too much on the numbers but assess where the imperfections are. If you can account for them, do so. In a manufactured tool where say… its build tolerance is plus 2/10ths of 1000th of an inch and minus 0, you cannot improve any error that causes. In general terms, metal working requires more accuracy of fit and finish than wood does. Plastics can lie somewhere in between, depending on where the machining has left the unfinished edges.
Wood is generally something that can be worked to tolerances from around 1mm to 1/10th of a millimetre is you have the energy and the tools to provide that level of accuracy. The take home message is try not to fret over things you cannot change and only work on the things which will improve your work practices by making them easier and producing better results.
If all of your modules are not performing as you expect, if it were mine, I would opt to disassemble and reassemble the machine again. If you are going to try that, look at whatever assembly videos you can and then step by step assemble the machine in its permanent location but eliminate the possibility of assembly caused faults like ensuring that every piece is mated to another piece exactly square and perpendicular. A small engineer’s set square may help you with this. Don’t rush the assembly and tighten all bolts and screws to the same tension. You can achieve that by tightening screws along the framework sequentially. Do not tighten just one and then the next one because that may apply deforming forces to the framework. Aim to have all of the frame holding screws almost tight so that is the smallest amount of loose play in the frame and that pushing it from one direction may change its relationships between the parts. when you are confident it is sitting square, tighten the bolts/screws in a sequence that does up the ones furthest from each other (opposite corners first) then work inwards. That should help to keep things straight. You may need a second pair of hands to help you with this process.
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I think the boundary run function could benefit from having either a stop button or better yet an automatic stop if there is an obstruction.