Finally got my A350 and enclosure. Overall I think it will be worth the wait. Yesterday I tackled my first CNC project. I use Fusion 360 and after watching conflicting videos was able to figure out how to load the machine config cps files. Adding the bits were pretty straight forward and easy.
Anyway designed a pretty simply carving and what I have found is that the bed is not acting even close to level. It seems deeper on the left than on the right and when manipulating the CNC head and checking level with a paper it drifts from lower on the right to higher in the left. I have confirmed the build of the overall unit. All screws and structures are tight and secure and the wooden bed seems to be fine. I didnât notice this with the laser attachment but I believe there is more tolerance on that device. It looks that the drift on the CNC is about a mm or so.
Is there anyway to perform a bed leveling for the CNC? I thought the unit had auto leveling but I now have learned that only applies to 3D printing (which really doesnât make a lot of sense to me). For cutting fine parts for my drone etc, being off a mm left to right is a non starter. I read someone trying to shim that that sims equally inaccurate. Can anyone provide any thoughts or insights?
I know your feeling, I had a few failed pcb mill because of this. This topic has been discussed in multiple occasions in the forum, you can find one of my answer below. Disclaimer: i havenât tried this option yet, but will be my future plan.
I have this exact same problem. I used the CNC module with a bit to manually touch each corner of the aluminum platform with the calibration card and recorded .035" (0.9 mm) slant between corners. Its repeatable. Iâve read the âmachine the MDF table parallel with the X-Y axesâ comments, but that seems like a lot of machine time just to get a datum. Iâve been thinking about 3-D printing a platform âshimâ to adjust for the level issue, with matching hole patterns to install between the aluminum platform and the MDF table. Not sure how much structure one would need to make it sturdy enough, but the critical dimensions would be the heights at the screw holes. Possibly trial and error, and some geometry in Fusion 360 of course. Open to suggestions.
Get a spoil board surfacing bit and it doesnât take very long. (Youâll need a matching er11 collet for the larger shank.)
Much less time than trying to figure out some workaround that still wonât be as accurate.
I got my 1" dia surfacing bit and 1/4" ER11 collet.
This bit wonât plunge, so I have to enter from the side of the board where it fully exits the piece, which is the left (as looking at the touch screen). It will not fully exit the board from any other side, but I think thatâs ok.
Pardon my inexperience here. Iâm getting hung up on trying to create a model when really all I want is the tool path: Manually set bit height, start at (0,0), move to (Xmax,0), then move back and forth moving in Y-axis increments slightly smaller than the diameter of the bit until I get to (Xmax,Ymax). It would be a square tooth pattern.
I can calculate this path just fine with pencil and paper. But what would be the best way to get this into Luban. Its not clear how to sketch and dimension anything but a rectangle or oval in Luban.
Feel free to link me to some other thread that probably has this solution.
There may be cheaper ones but Iâve had really good performance out of Whiteside bits over a lot of years of woodworking. I find they work great and are a really good value. I picked up a variety of 1/4" Whiteside bits from https://www.eoasaw.com.
As far as collets go I just picked up a variety pack on ebay. Just need to be er11 collets.
-S
I acquired bit and collet. Now how to I set up a tool path in Fusion360, and which tool would I use there when I donât know the manufacturer of my bit. I only know that it is 6 mm shaft and 1 inch diameter.
Manufacturer doesnât matter. You can search for a flat end mill or facing mill in the defaults that is the same size (or edit one of the presets). For this the cutting radius is the only thing that matters.
Iâve found a .2 step-down at 400mm/m works well. May be a little conservative but Iâd rather not burn out my toolhead. I just run a single pass with that .2 as cutting depth and then run another if needed. You can also do a .4 cutting depth and a .4 stepdown and then just back off .2 or .1 on the work z height if you want to see if you can push it a little more.
Make sense? Let me know if I need to clarify anything. I know how bewildering and overwhelming all these terms were when I started and hard to know now what is just gibberish to new people.
-S
@sdj544 Sorry for bumping this somewhat dated topic. I just wanted to chime in and ask for your experience regarding rotational speed with your 1in router bit? Did you run that thing at 12000 rpm?
Iâm somewhat concerned about the 8x surface speed that will result by that diameter. While I read somewhere on the net⢠that 180-300 m/min may be ok for wood, however, the surface speed I would calculate for 12 krpm with a 1in router bit would be somewhere in the 960 m/minâŚ
I run my 1" spoilboard bit at 12000rpm, 400-800 mm/min (depending on the material), at 0.2-0.3mm steps. Iâve never had issues, and have had good finishes. For the MDF board, I did 800 mm/min at .2mm step down. It worked great.
One caveat though, on hard wood I run it only on climb. Iâve found I get a little chatter when running conventional.
Iâve found the online calculators useless with SM. They assume a certain amount of torque/power which the SM doesnât have.
I always run wood at 12000 rpm. Only with acrylic and other materials like that where youâre worried about melting that you need to slow down.
Same speeds and step-downs as @BluegrassBlaster uses works well for me.
Thank you both for your insights. I was only doing a rough calculation myself, not even considering torque at all. So Iâll give it a try myself as well like that.
Where can we change the RPMs? Iâve been running acrylic and having a rough time with melting and whatnot. I donât see the option in the Luban tool settings. What RPM do you recommend for acrylic?
Havenât done any acrylic cnc personally. I think I remember people suggesting ~600 rpm.
Are you using cast or extruded acrylic? Big difference in how they respond to cnc.
Plexiglas is a brand name of acrylic. Doesnât tell whether itâs extruded or cast.
Extruded is much harder to work with for cnc as it has a lower melting point.
Looks like Luban doesnât allow you to change spindle speed. Could always edit the g-code.
And there are a lot more internal stresses in the material which can cause it to just break/crack and whatnot.
I canât check at the device right now, isnât it also possible to change the spindle speed before starting or during the job? (like you can change the overall working speed). (swipe from right to left on the touch screen once the job has started)
Forgot to mention trying that. Youâre supposed to be able to, but I believe some people were having problems with it. Like laser power if there is a command in g-code it ends up overriding what you do with controller.