I have a work bee 1010 with a black box controller, with a craftsman 2hp router that I bought from someone. The issue I am having is when I clear a pocket, the bottom always comes out uneven on larger carves. I've attached a picture to show. The upper right (smaller version) was created in Easel, the larger version I used Etslcam to create the g code. Both are having similar uneven results. I have set the XY&Z step calibrations. I'm pretty new to this so any help would be greatly appreciated. Thank you
Hi Kendall, Almost looks like your Z coupler isn't tight and you are not getting a reliable z position. Another thing it could be is backlash from a nut block that is to tight or wheels set too tight. Is this with a downcut or upcut endmill? 2hp router probably heavy for a c-beam? Have you tried a light finish pass? Cheers Gary
thanks for the response Gary, it's an upcut 2 flute bit, the total depth was set at .040 with cuts at .028, how tight should the wheels be and the nut block?
The wheels should be snug but still able to spin them with your thumb. The nut block should be easy to spin but no slop. Cheers Gary
If it is not a mechanical issue, what is your grbl $1 setting? A 2 HP router is a little heavier than what these machines were originally designed for. I did not have mine set to $1=255 and my Z axis would drop causing different depth cuts similar to what you are showing. Grbl v1.1 Configuration · gnea/grbl Wiki Although looking at the picture, there seems to be something more going on, have you made sure the router has been trammed. In other words it is not tiled forward, backward, right, or left? If it is not trammed properly, you will get lines where you cut. Tramming: Generic guide
thanks Gary, my $1 is set at 255 the cnc has been trammed and I surfaced the spoiler board. If you look at the larger picture, (rotate it counter clock wise 90 degrees) that whole area where the grooves appear is supposed to be pocketed out, you can see that the router appears to lift up in the middle of the carve leaving a blank spot. The top picture is just a smaller version, the pocketed areas are there but the bottom is very uneven, some places are not even cut...that is the issue I am having
this is what it's supposed to look like and this is the carve I'm getting, I wrote in where it was supposed to cut but didn't. Any suggestions would be greatly appreciated
Try a brand new bit and greatly reduce the amount of stepover and the feed rate. The bit appears to be skating across the bottom. You're pushing it way too much and it's just climbing out of the hole. Also get some bit cleaner. Gummed up bits will do the same and plywood is notoriously bad when it comes to gumming up bits.
Thank you Rick, Here are the current settings I used for the cut total depth of the cut is .040 1/4 bit new feed rate is 40 ipm step over is 75 % Let me know what I should change it to and I'll try that and see what happens. See new pic, I did do another carve, the hello world from OB in mdf it was uneven also. I've use 3 different gcode generators and 2 different controllers and still come up with the same issues
With the bit removed, put your hands under the collet nut and push upwards with plenty of pressure (more than the weight of the router) and see if you get any movement. If so, adjust the Z leadscrew collars to take up any play. Note that the flexible coupler must never take any of the Z assembly weight. For a .040" cut, your feed rate could be nearer 100"/min. Do you know what RPM the router is delivering?
I am away from my shop at the moment and be back later this afternoon and check for movement and post the results. I have the rmp set at about half so maybe 12-14K rpm
Ok, there was some slop on the Z axis, I rest the lock collars so everything is tight now, I set the step over to 50 and the imp to 75, .040 total depth, a new bit, it is still having the same issue, I did another cut after tightening everything up with not much difference......is the router to heavy? ...is there a next step? or chuck everything and start over with something else I do want to thank all of you for the suggestions, much appreciated!
Ok, on a whim, I removed the dust shoe and reran the cut...viola an even bottom. I'm guessing the weight of the router, the dust shoe and the hose was a bit much and causing the problems. thanks again
Was there any chance the dust doe was hitting the work piece or clamp? I have had that happen and the z axis lost steps an the project got messed up.
How are you accomodating the hose? Swing Arm is a good option - the heavy hose tugging on the toolhead could very well be the main reason (more so than weight which is more constant)
Good! I was looking at that pic and was thinking, I bet that dust shoe is getting smashed down too much!
I had one of these dust shoes that I adapted down to 2-1/2 hose, I did have a hanger ( I used a cell phone holder to hold the hose) for the hose so it didn't flop or put undo stress on the router. Yes the brush did squish down some depending on the bit length, going to change out the dust shoe to something smaller along with a smaller router. The one I had (2-1/2hp) was the one that came with the machine when I bought it. The guy I bought it from built the machine (sort of) and then didn't or know how to use it. I didn't know much about cnc's, I know a bit more now, thanks for the input and advice
If you change the router may I recommend a spindle? My spindle is 1.5kw but it's way too powerful for what I do, which is mostly wood and plastic. A 800w spindle would do just fine, for me. If what you do is the same like me get the 800w, otherwise the 1.5kw. They are not expensive on AliExpress BTW, the spindles are very quiet. My main noise maker is my shopvac. Next, in the noise makeing, is the bit cutting the wood. You don't hear the spindle at all.
