SoliForum - 3D Printing Community — Moire - Might not always be in the printer

Re: Moire - Might not always be in the printer

2013-10-24T10:51:58Z

I think everyone will find that running 1/32 microstepping on ALL axi (particularly with a fine-pitch z-rod) means you slam into Marlins 10KHz planner limit... 40000pps which often has 4 steps a planner loop, which means its a 10khz limit .... looong before 'decay' becomes an issue...

Re: Moire - Might not always be in the printer

2013-10-24T00:08:30Z

2n2r5 wrote:

I don't know which version he did that on.

If you look at the pic closely at the photo on http://reprap.harleystudio.co.za/?p=321, it shows the '01C' connection, which makes it a MD20B.

MD20A:

MD20B:

Re: Moire - Might not always be in the printer

2013-10-23T23:56:58Z

I don't know which version he did that on. I have the MD20B. That might be the MD20A which needed a hack to get to work correctly. Adrian ended up with those. I think it needs a 4.7K pull up resistor in-line some where to work. I do have a couple spare DRV8825 md20b drivers that are questionable. I will test this out and see how it does.

Re: Moire - Might not always be in the printer

2013-10-23T22:12:59Z

Have you tried this mod 2n2r5?

http://reprap.harleystudio.co.za/?p=321

Re: Moire - Might not always be in the printer

2013-10-11T19:12:27Z

2n2r5 wrote:

techbuilder2175 wrote:
Hi 2n2r5,
Did you ever think of adding rickq front bed stabilization?
http://www.soliforum.com/topic/3407/fro … ed-wobble/

Yep, sure have. I have to acquire some parts. I think I may just use bearings on a spring loaded arm. I am a little concerned about how much pressure I will be putting on the sides. My bed has a bunch of play when you lift the front of the bed. I don't want introduce any backlash in the bed due to excess pressure keeping the front of the bed from falling.
Or,
I ignore the problem and build my new machine.

Your so close though!
I would make this the last thing you do to your solidoodle
just so you can have closure lol

Re: Moire - Might not always be in the printer

2013-10-11T18:53:19Z

techbuilder2175 wrote:

Hi 2n2r5,
Did you ever think of adding rickq front bed stabilization?
http://www.soliforum.com/topic/3407/fro … ed-wobble/

Yep, sure have. I have to acquire some parts. I think I may just use bearings on a spring loaded arm. I am a little concerned about how much pressure I will be putting on the sides. My bed has a bunch of play when you lift the front of the bed. I don't want introduce any backlash in the bed due to excess pressure keeping the front of the bed from falling.

Or,

I ignore the problem and build my new machine.

Re: Moire - Might not always be in the printer

2013-10-10T18:38:07Z

Hi 2n2r5,

Did you ever think of adding rickq front bed stabilization?

http://www.soliforum.com/topic/3407/fro … ed-wobble/

Re: Moire - Might not always be in the printer

2013-10-06T15:18:49Z

Velocity is the rate of change of position.
Acceleration is the rate of change of velocity.
Jerk is the rate of change of acceleration.

Re: Moire - Might not always be in the printer

2013-10-06T15:04:02Z

johnforeman wrote:

What is the X-Y jerk tuning?

edit: see Tim's comment

There isn't a tuning option really. You can just alter the value in the Firmware EEPROM Configuration. I would suggest not changing the default value unless you are comfortable with it.

Re: Moire - Might not always be in the printer

2013-10-06T13:43:34Z

Excellent thread, thank you.

Re: Moire - Might not always be in the printer

2013-10-06T11:18:05Z

What is the X-Y jerk tuning?

Re: Moire - Might not always be in the printer

2013-10-06T01:33:31Z

I'm like 70% sure that it is my filastruder filament. I think the auto white balance on the camera did that. The back ground should be a bit more yellow than it is.

I'm going to go ahead and say it is.

Re: Moire - Might not always be in the printer

2013-10-06T01:19:19Z

Is that Filastruder filament? It looks too white for ABS natural.

Re: Moire - Might not always be in the printer

2013-10-06T00:59:57Z

After doing everything that one could do to eliminate moire caused by the extruder stepper motor I started looking at other factors. I looked through a bunch of prints from other printers and noticed that even at its best, my printer was having trouble matching some of the big dollar printers. One of the biggest differences was how the bed was supported. Every other high dollar printer seems to have a wider support structure or the bed is supported from 2 sides.

Before: This is my basic print at .15mm layers @ .3mm Wall width. I generally run around 60mm/s for a standard print. I also have X-Y jerk turned up to 30mm/s to take advantage of my bigger steppers and stiff spectra line drive.

After: .15mm layers @ .3mm Wall width at 75% feedrate and 20mm/s X-Y jerk.

The difference is very noticeable. Slowing down the print and reducing the X-Y jerk muted the ripple substantially. You can see that corners are no longer followed up by a deep ripple. All other moire is all but gone. Not only am I happy with this print but I am done trying to get better quality. The only upgrade that would help me with quality is a bed support system for the front.

Re: Moire - Might not always be in the printer

2013-09-18T23:08:40Z

Stevos758 wrote:

Can you point me in the direction to some pics of your setup? Is there any mods needed for the new stepper or is it plug and play(besides firmware settings?)

I won't be able to get you pictures until the weekend probably but there isn't much to see. It is a direct replacement for the stepper motor already there. Just longer and now without a fan.