Z is gaining or losing steps

I can’t get a successful 3D carve to save my life. I have searched the forum many many hours in an attempt to fix my problem. My z gets deeper as it goes. I send the bit to zero after it’s complete and it is below zero every time. I’m wasting a ton af material and time. I run a test carve after each attempted repair for about 5 hours. I’m so tired of this.

I got my xcarve within the first three months it was released. I have 1000x1000, Dewalt router, x controller, stiff x rails, dust boot. I put a flat spot on my z stepper shaft with cap head screws in the pulley. My acme lead screw just has new screws in the pulley, I plan on putting a flat spot on that tomorrow. I checked all my wiring, adjusted my pots probably 10 times. I’ve been fighting this starting last November. I run my 3D finish with 1/8 ball nose,120 ipm with 8% step over and plunge rate of 50.

I design with aspire and use picsender for sending gcode. USG and easel crash on large jobs. I have no way to test another sender because picsender is the only one I know of for large jobs. I happen to love picsender. It has never crashed once in the 6 months or so I’ve been using it. However I do not have a post processor for picsender and use

Cnc shark inches in aspire to save my code. I may be having an issue there. Any help would be welcomed.

Aspire should already have a x-carve post processor in the list

Software is not your issue…hardware is. If you are losing steps it’s either your belts or motor. If your belts are properly adjusted and your motor amperage set properly, slow down the Z axis maximum speed. These are the three areas for your problem.

I have the post processor for easel but I don’t use it often. Easel can’t run large 3D files.

Thanks. I’ll check then slow down my plunge rate more.

I didn’t mean the easel post processor. Aspire has a dropdown list with all post processors, there is a x-carve one or you can find them here: https://www.inventables.com/technologies/aspire.

But like Dan said it’s probably hardware related

I agree that’s it’s probably the hardware. I thought I fixed a few times but it failed again late in the carve. I’ll keep working on it.

My aspire didn’t have that. I will add the x carve post processor. I never knew where to find it. I only recently added the easel one. Don’t think it’s my problem with my Z but I’ll feel better using the correct one.
Thanks

Check your collet nut, make sure it’s tight. (Just happened to me last week)

I did, I even purchased a new router. Now before each test I put a mark where the bit hits the nut. I had some issues with slippage when I first got it.

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Also check you have continuity on all four motor wires for the Z-motor, if one is broken/disconnected the motor will spin its said amount of steps, but direction will be at random.

Try a piece of tape on the z-axis to observe it turning during a carve? (I’m thinking 2.5-d carving, where the z doesn’t change during a horizontal cut)

Swap a servo. If it fixes it, it was either loose wiring or the servo. Run some manual move tests using either the console or a serial client (i.e. PuTTY).

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I have tried the tape thing but it always lined up, actually I used paint but same theory. I’m thinking now that I did it wrong. I marked the pulley and the belt. They lined up for months until I replaced pulleys. I should mark the pulley and the stepper motor shaft. The way I did it only told me that the belt was not slipping on the pulley. It didn’t let me know if the pulley is slipping on the shaft.

It’s very reliable on more simple stuff like v carve signs, pockets and profile cuts. I did this 6x6 aluminum .03 deep at .01 per pass. Carved for two hours and looks good. It refuses to do a long 3D cut. If I give the Z a good workout it messes up.


I checked my wiring for tightness last night, all was good. I’ll swap motors tomorrow. I guess I should check my pots with a voltage meter, I’ve been letting it air carve a 3D finish and adjusting by ear. Maybe I’m just bad at that.

Y’all are probably correct. I have seen a lot about the pulleys on here. I purchased new pulleys, z belt, cap head screws for pulleys and acme screw and nut. I made a flat spot on z motor shaft. I can see it is still lined up on flat spot. I don’t know why I didn’t put a flat spot on acme screw. I will add that to my list of things to do to resolve my issue. I used lock tight on pulley set screws.

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Get some blue locktite if you do not have any already.
use them on the pulley plugs as they tend to fall out.

Thanks for the help everybody. Nothing worked, I even put on new parts. Router is tight in the mount, bit didn’t slip, belt is tight and not slipping, flat spot on z stepper and acme screw, cap head screws in new pulleys with blue loctite. I’ve been fighting this thing for two years, solved everything but this.

Another thing I think is odd is that after I got the x controller the motors don’t hold very tight. It’s easy to accidentally move things when changing bits. Before It wouldn’t move if I shoved on it. I’m going nuts and so is my girlfriend. I’m spending a redicoulus amount of time working on this thing.

You should activate idle current (power ON for motors that are stationary, IIRC that is a dip switch setting.
Also check GRBL value $1 and make sure it is set to 255.

Z-axis accelleration is another part of the equation and worth checking/testing with a lower setting.

For each axis, DIP switch #4 needs to be turned OFF to disable auto torque reduction. With it on and the motors idle, you get a 70% reduction of your output current, hence why they are easier to move.

Also, make sure your pots are set properly.

My $10=3