Creating a lip during pocket cut

I have the Shapeoko 4 XXL. I created two separate projects and they both came up with this lip on the ends.



So I checked the belts and tightened what I think are the pully motor screws. Some of the screws were loose but when I tightened them the y axis is now catching when I move it manually. I attached a video to see.

I don’t have any idea how to fix this thing mechanically so please dumb down any suggestions.
Thank you!

It looks like your moving that X beam pretty fast making the Y motors generate electricity, that’s normal. Is it still jumpy / rough if you were to move it slowly? My BitZero and BitSetter lights glow it I move mine to fast.

2 Likes

If you are moving the gantries by hand, it is always best to disconnect the motors.

The motors will act like generators as you push the gantries around, and the electronics are not really designed to handle that kind of backfeed energy.

1 Like

While you are in the area, putting witness marks on all the pullies will make it easy in the future to see if something has come loose.
IMG_1797

2 Likes

Do you have a reference? Or a schematic?

1 Like

Only the recommendations from C3D not to do that.

1 Like

The noise is normal when the gantry or any other stepper motor is forced to move. A better way is to use the jog feature.

I think you were on the right track by tightening the belts if you didn’t do all of them you should check and tighten all of them. I would also check every bolt, screw and fastener on the complete machine (I would bet this has not been done since you assembled the machine). I check all the fasteners about every two months or once a month if I am doing a lot of cutting.

I would also use the jog feature or a remote controller to move the machine x, y, and z axis with the router off and listen to the sound of the motors and see if you hear any change in the sound of the motors this could indicate a wiring/connector problem. One of the test in the automotive industry when checking wiring and electronic components is a wiggle test of the wiring and components. You could also do this test while moving each axis. Most problems will be with the connectors.

The motor sound when moving the axis with the computer or controller will be a smooth and steady sound. If there is a problem it will make a sound that is like someone just pressing the jog button really fast and cause the axis to jump or sound like it is being hit, it is basically being started and stopped really fast.

Hope this helps
Anthony

1 Like

So now it’s doing this on the x axis. Everything appears to be running smoothly except it messes up in this spot. I’ve tightened every screw on the machine and the belts are as they should be.

Please post the .c2d file.

test.c2d (64 KB)

I ran the same test on 1/2 mdf and it seems to be fine??? Guess is could have been a fluke?

Or a lost step in the harder material. Which is correct, the thinner or thicker portion of the contour? And was that at the start or end of the path?

1 Like

Try reducing the depth of cut. What router are you using and at what speed? You could also increase your speed to decrease the cutting forces. (Assuming your feed rate is appropriate)

2 Likes

Are you cutting a slot at this point? What is the depth of the slot? What is the cutting flute length of the tool being used?

Makita router on 3. Thank you I’ll try reducing the depth of cut.

I’m not sure what you mean by cutting a slot.

1"

Cutting a slot is making a cut the same width of your endmill. So if you’re using a contour toolpath path to cut out a part with no additional offset, thats slotting. Best practice is to cut out parts using offset geometry. All that means is creating an offset around the part you’re cutting out equal to the diameter of your endmill plus 10 percent of so. Then you select the outline of the original geomtry and the offsett and cut out as a pocket which is easier on the endmill :slight_smile:

Thank you! Learned something new!

I cut it as a contour. It’s only 1/2" poplar so thought I wouldn’t need to.

I decided to try my welcome sign and it was going great until the very end it took a chunk out of my “c”.
Welcome Pumpkin.c2d (372 KB)