So I had the printing running fine then everything went haywire on me.

So I had the printing running fine then everything went haywire on me. The hobbed bolt keeps chewing filament and I seems to be getting a pretty bad knocking sound from my stepper but I can’t figure out witch ones.

Prints are turning out horrible and the hotend seems to be digging into the last layer printed i didn’t have these problems a week ago and nothing has changed.

Pic and video uploaded.

Any suggestions.

Could it be that the layers are turning out thicker than they used to? The clicking could well be the extruder with back pressure forming at the nozzle, as plastic can no longer be squeezed out.

Ya I don’t know what’s going on seems like its pushing more out than its supposed to, even though I told it to tone it down.

The popping is mechanical in some way as it does not sound like back pressure. It sounds more like metal hiring it self or seizing for a sec then starting again.

have u calibrated ur machine thoroughly? filament feedrate too high? try printing those 1x1x1 thin boxes to test. n ur Z seems like its pushing itself against the printed object?

Ya I’ve been calibrating this thing for like 2 months it always seems to screw up and de calibrate it self. So I’ve probably calibrated this printer like 50 times.

Ya it does seem like the z axis is not rising enough on each layer progressively going up smaller increments.

I’ve had my feed rate any ware from 600-700, just around the 700 range is ware it pulls in 5mm of filament 698 or something like that.

Oh and yes I do the little 10x10x10mm cubes to calibrate.

It looked like your belts were slipping a tooth.

so do you notice very bad ridges in the cube? did you calibrate the stepstick current? to minimize miss steps?

Ya I went through the hole calibration about 3 time the stepper carriers are calibrated, the steps per mm are calibrated as well for x y and z took me forever to find the correct steps.

The cubes I print are solid. But when I did have it printing it did really well on bridges almost not dropping at all. Just a small sometimes a small curl ware a strand had broke.

Are the set screws on the stepper pulleys square and tight? It sounds/looks like they’re intermittently slipping.

Ya there as right as I can get them without stripping the out. I get the illusion that they are slipping as well sometimes.

Maybe turn down the maximum acceleration then? Perhaps it’s just trying to go too fast on travel moves.

Ok so it’s currently set at 3000 should I half that?

Yah. Try 500. It’s low, but it’ll give you an idea if the acceleration is the problem.

Ok ill try that tomorrow after I recalibrate the machine and let you know how it goes.

Cool. Note that you can change (reduce, really) the acceleration settings in slic3r if you don’t want to reflash the firmware. My max acceleration is set to 1500 on my mendelmax, and I usually print with 500 to 1000 in slic3r.

Well noted I will do that.

Doh, but slic3r may not slow down for travel moves, so maybe firmware flashing is the best way to test for this possibility anyways.

Ya ill run it through the EEPROM it’s a lot easier than reflashing.

If your x y axis was slipping, your prints would be misaligned and it doesn’t look like that’s your problem. Could be a loose or dry stepper connection or even a faulty stepper driver. How’s your free air extrusion look, any bubbles or inconsistencies in the extruded filament?