SoliForum - 3D Printing Community — SD3 Y axis skips

Re: SD3 Y axis skips

2014-05-10T20:24:44Z

Do you still have the stock carriages on your machine? After maybe 200 hours on the machine, mine was skipping in the Y axis too, sometimes quite badly. I did every belt adjustment technique in the book with no good results. A lot of the electronics adjustment are beyond my current level, so I was really hoping it was not that. I ended up printing the lawsy carriages and I have not had a bit of skip since! (knock on wood). It just seems like the stock carriages are not robust and are prone to binding.

Another thing to note: almost every time I have had skip, I have found hairspray on the rods. Clean them frequently. It helps to lower the bed to the bottom before applying hairspray if you go that route.

Re: SD3 Y axis skips

2014-05-09T23:51:58Z

Does any one know waht stepper motors are used on SD3?
Nema 17 1.8 degree 1.7Amp or what?
Especially interested in y axis.

Thanks ahead.

Re: SD3 Y axis skips

2014-05-06T13:55:43Z

Yeah that will do it too usually the binding from the belts is because the carriage is getting it's angle changed with one end moving more than the other and even though the stock bearings SD uses are self aligning they don't align very good with small angle changes, sometime a sharp tap to the side of the bearings will 'align' them, also make sure the y carriage is perpendicular to the x axis when adjusting the belts... ie don't just tension one belt without making sure the back pulleys are loose. There are some good posts on here on how to properly tension the belts, as long as you follow one of these you should be good.

Re: SD3 Y axis skips

2014-05-06T12:27:35Z

ronsii wrote:

Missing steps in one direction is pretty common with the Y axis, usually it is because the two side bearings are binding because of mismatched belt tensions and the added force of pulling filament.

Thanks for the advice. Will check belt tension later today when i get back home from work.
Last time i had skipping like that was due to extruder power cable hitting one of the Y belts. that is not the case this time.

Re: SD3 Y axis skips

2014-05-06T05:02:42Z

Missing steps in one direction is pretty common with the Y axis, usually it is because the two side bearings are binding because of mismatched belt tensions and the added force of pulling filament.

Re: SD3 Y axis skips

2014-05-06T04:01:33Z

Quick update.
At 0.6V VREF the y driver stops after about 50mm of head travel, so I am guessing 0.6v is over the top for the driver.
0.55v seems to work, but now i need to recalibrate the printer; the print-head "floats" from one y path to the next; as if it moves in positive direction more than in negative.
On second thought recalibrating the printer probably wont fix it; if it was as simple as linear cal issue then y paths would be longer/shorter than intended; but in reality when head moves in positive y direction it moves further that it returns back moving in negative direction.

Re: SD3 Y axis skips

2014-05-06T02:51:54Z

I would adjust that VREF by feel and see if you can get better results. You seem to have a good feel for force produced so don't get too hung up on exact voltages.

Re: SD3 Y axis skips

2014-05-06T02:42:14Z

pcm81 wrote:

The Y stepper driver was at 0.508V instead of recommended 0.52V adjusted to o.518V.
Will test tomorrow.
Any bets on if this was the only problem or if my motor is indeed shot.
make your bets people.

Just checked the "stopping force" on Y axis after the stepper driver voltage adjustment to 0.518V from 0.508V. The Y axis still skips with much less resistance than is needed to stop X axis. Tried by hand, so no exact load characteristics... I'd guess 5 to 10 times less force needed for Y stepper than is needed to stop x stepper.

Re: SD3 Y axis skips

2014-05-06T02:35:54Z

I think you will find that with a good PSU and the Rumba. Your motors will perform better and be fairly adequate. If you order the Rumba with the 1/32 drivers you can choose via switch to run at 1/16 or 1/32 for each driver. Also you can run a separate PSU for the bed heater. Over all it is well worth the money and extremely robust. I won't go into details but I have done things to my Rumba that certainly would have killed a lessor board.

Re: SD3 Y axis skips

2014-05-06T02:23:02Z

The Y stepper driver was at 0.508V instead of recommended 0.52V adjusted to o.518V.

Will test tomorrow.

Any bets on if this was the only problem or if my motor is indeed shot.

make your bets people.

Re: SD3 Y axis skips

2014-05-06T01:43:54Z

ronsii wrote:

If you haven't tuned the 'pot' for adjusting the voltage out to the stepper motor this could cause the lack of torque if it is not set right.

Have not adjusted the pot; however SD3 worked well for the last year...

What are "the best" stepper motors i can use with RUMBA controller? I pretty-much decided to move to RUMBA (dual extruders upgrade will come in the future) and want to upgrade steppers along the way.

Thanks

Re: SD3 Y axis skips

2014-05-06T01:12:51Z

If you haven't tuned the 'pot' for adjusting the voltage out to the stepper motor this could cause the lack of torque if it is not set right.

Re: SD3 Y axis skips

2014-05-05T23:09:54Z

bnj wrote:

Well, I heard the Rumba is just the big bazooka of 3d printing. This is the card to go with definitely.
Now, I'm running a sanguinololu, with a Atmega 644, and didn't felt the urge yet to upgrade it. But as many electronic components out there : cooling is the main thing.
Everything carrying intensity needs to be refreshed. Your stepper is fried, that's for sure. It acts the same when I fry an ESC on one of my quadcopter. Motor just spins, but when you load it, it stall.
If I were you, I'll just order a good stepper, for 10 dollars online, and put it on the extruder (a micro stepper 32 is better), then swap the extruder stepper to your Y stepper.
Then, if you want to keep it DIY, you do like me : you drill the plate that protects your main bord with many holes, and zip tie a big fan on it. This will refresh your steppers, and give them more life.
Next step will be to give them a heatsink, and ultimately upgrading the board to a Ramp or a Rumba, that will give you more expanding possibilities like a Gcode extruder fan, LCD control, and many other things.

You gave me a good idea to go along with my fresh plan.

I always wanted to go dual extruders and since i have an all metal extruder+hotend sitting on the shelf i am going to stick that on the carriage, put the extruder motor in y motor location and i am going to replace main board with RUMBA. This was always the long term plan, but now the schedule has been expedited.

Thanks for extruder / Y motor swap idea.

Re: SD3 Y axis skips

2014-05-05T23:04:01Z

Well, I heard the Rumba is just the big bazooka of 3d printing. This is the card to go with definitely.

Now, I'm running a sanguinololu, with a Atmega 644, and didn't felt the urge yet to upgrade it. But as many electronic components out there : cooling is the main thing.

Everything carrying intensity needs to be refreshed. Your stepper is fried, that's for sure. It acts the same when I fry an ESC on one of my quadcopter. Motor just spins, but when you load it, it stall.

If I were you, I'll just order a good stepper, for 10 dollars online, and put it on the extruder (a micro stepper 32 is better), then swap the extruder stepper to your Y stepper.

Then, if you want to keep it DIY, you do like me : you drill the plate that protects your main bord with many holes, and zip tie a big fan on it. This will refresh your steppers, and give them more life.

Next step will be to give them a heatsink, and ultimately upgrading the board to a Ramp or a Rumba, that will give you more expanding possibilities like a Gcode extruder fan, LCD control, and many other things.

Re: SD3 Y axis skips

2014-05-05T22:18:56Z

Rumba