Missing steps

All of a sudden my printer which is an Original Mendel running Gen6 is stepping over to the right during prints for a few layers then stepping back again. This has happened on 3 prints in a row today and yet yesterday I printed all day without any problems.

Running Repsnapper on a Win 7 netbook. Prints are Prusa parts which so far have been printed 50 times without incident so slicing hasn't been changed Gcode is untouched from the previous 50 prints.

Belt is still tight and once it stops printing now am going to check the pulley is not slipping.

It's only moving across one step so I can live with it for now but is damn annoying.

Anyone got any suggestions?

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Experimenting in 3D in New Zealand

Did it again today but only on one of the prints not the second one. Going to try a different USB port tomorrow and if that doesn't solve it am going to drop one of our Sanguino boards on and see about setting up a SD card to print from

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Experimenting in 3D in New Zealand

Hey Gary,

I had a similar problem a while ago and found that the y and x belt were rubbing on the fender washer at the idler and were binding.

I put a bolt just below the belt at the idler end with a fender washer and electrical tape to keep the belt in the center of my idler bearing and no further problems.

I have also started printing from sd card and had no dramas so far. The one thing I found is the sd print will start regardless of the hot end or bed temp so this must be right before you start the print. Btw I have pronterface temp set to zero so I can modify the temp on screen and on the fly, so this may have some input

Not the same issue as the Original Mendel is built completely differently to the Prusa. Really must get my Prusa up and running. Have turned up the power to the X stepper driver a fraction

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Experimenting in 3D in New Zealand

found a fry bearing on the X belt. Oiled it and the problem so far hasn't come back. Fingers crossed on this one

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Experimenting in 3D in New Zealand

This problem still exists

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Experimenting in 3D in New Zealand

I have RAMPS 1.4 and pololu stepper drivers and I had the same problem in the Y motor.

I interchanged the X and Y motors and the problem was now on the X motor so I isolated the problem in the electronics, not the motors or mechanics.

I don't know Gen6 electronics but pololu drivers have a potentiometer to calibrate the maximum current allowed and I had configured that setting too low. I increased the trim a little bit and the problem was gone.

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Ernesto Pareja

dcctrains.netne.net

I had a problem with the motor wire connector that plugs into the 4 pin header on the RAMPS board. I guess the contact surfaces were not adequate for the amount of current the motor was pulling. So I removed the connector and header and soldered the motor wires directly into the board.

Also fan and heat-sink may help