Hi everyone,

I’ve just started learning Reprap firmware and Duet architecture this week. Have some simple printers that I am working on starting a home business with and, with the help of Ali and digitmakers.ca, got turned onto Duet3D.

My printers are my 1.5 year old Creality CR10S, and my two recently purchased Creality Ender5Pro and Plus.

In the Late fall of 2019 I bought an MKS board and touch screen. Never got it installed. Was getting tired of Marlin. So I bought a Duet 2 Wifi. Christmas came around and I never actually installed it on its intended printer, the CR10S.

Well, this week I finally did. Learned my way through all the setup and software. Once you get to know the basics of the firmware, and the web control, it makes Marlin look like an Abacus.

So I picked two Duet Maestros for my two ender based printers.

Halfway through the E5Pro, and will get to the Plus this weekend.

So I just wanted to say hello, and I look forward to discovering what firmware and hardware can do.

Thanks,
Ryan

@ChrisP said in Three printers, poor consistency, questions:

Don't forget though that the faster you print, the faster you'll need to get energy into the filament so at some point you'll have to decide whether you want to find the max VFR for your standard temperature or whether you're wanting to explore increasing temperatures to push the VRF up. Based on what you've said so far, I'd probably save increasing temps for another day once you have some nicely tuned profiles.

I'll reply to the sections before this in another post as the VRF aspect is important for the speed I am trying to determine I can print at.

Since I wasn't able to find any details beyond the "skipping" method, and figured I'd look at it and see how it can be modified to assist with bowden tube setups.

So the dozuki ender 3 guide suggests 50mm and increasing by 1mm/s. I'm assuming its being done with a 0.4 nozzle, and I'm using a 0.6 nozzle. But I did two things different.
One, I doubled the length in the guide. So instead of 50mm followed by 100mm. I started with 100mm, and verified with 200mm. The extra constant length over 50 gives more time for pressure to build up.

And two, I paid close attention to the bowden tube and its movements. Especially when the extrusion finishes. Anything more than slight flex, I lowered my feed rate.

1. heat nozzle to 220c
2. turn on part cooling fan to 20% (I may change this after some test prints)
3. extrude 100mm @5mm
4. increase by 1mm/s until poor bowden movement or skipping
   (both which seemed to happen at 10mm/s)
5. Decreased to 9mm/s, extrude 100, no skipping, but the flex was still there
6. Double to extrude to 200mm @ 9mm/s (poor flex and skip)
7. Stayed with 200mm but dropped to 8mm/s, nominal flex and no skipping

So based on that, I am going to use 8mm/s as the feed rate.

Max Flow Rate = Max Input Feed rate * pi * (Filament Diameter/2)2

MFR = 8mm/s * pi * (1.72/2)2 (I used 1.72 as I often get that result in filament measurement)

MFR = 18.5 or 18.

I'm going to test this and see how things change.

@bot said in Volumetric calibration question:

Make sure you keep the temperature high enough to maintain good adhesion of extrusion. There is a wide range of acceptable temperatures for some materials, but the faster you print, the higher you need the nozzle temp so that the heat can "soak" into the middle of the filament in the small amount of time it is exposed to the heat zone.

This was great advice. At the given 30mm/s test speed, I dialed in and 100% flow rate was perfect. But I rarely look to print that slow. So I upped the speed to 45mm/s and had to boost the temperature (215 to 220) to keep the extrustion adhering properly. Then 60mm/s, 220 to 230, but also had to turn the blower fan down from 20% to 15%, 66mm/s, I had to go to 235.

Your advice was so helpful to keep in mind while running this test.

I just finished my conversion of the my CR10S and my Ender 5 Plus to using separate steppers. Through my learning, you only need to add and U* parameters in the descriptions of your steppers (ei; jerk, accel, steps etc).

In all other instances (such as z probe offset), you simply need to apply a Z* parameter.

It sounds like what I have been working through for the past few days where my z-offset keeps changing.

As @Phaedrux said, use the probe. My process is very similar to yours.

1. home all axis

2. M564 S1 to make sure virtual endstops enabled so you can't go below 0 for Z

3. raise 8mm

4. probe bed

5. repeat 3 and 4 and review Z offset.

6. once I am locked in with my z offset, I reboot, home and check with paper.

But I was doing this over and over and over, daily. But this I learned about operating the dual z axis with separate steppers, and using G32 to align the leadscrews Even though dual z screws is supposed to help with keeping your gantry level, it never does.

I I made the need hardware changes and firmware changes, and can include G32 in my routine. I have found today on my CR10S I don't have to adjust my z-offset. Its rock solid.

I will also add that in all this change, I also positioned my probe (BL Touch as well) to be closer to the nozzle. So my z offset is much smaller.

So I would try

Dumb oversight. I have been using the same parameters for the probe offset, but completely ignored the fact that I just changed this printer from a Microswiss hotend to and E3D Volcano. Y offset was not correct.

@garyd9

Every single word you typed sounds like my experiences lately. Problems....solutions....why?....don't know. Same problem, different solution, why?....don't know.

This forum has proven itself invaluable when it comes to finding the solutions. The Whys are sometimes there, but other times it can be more like "Try this, it may fix it".

We all have to take out individual machines, and filter through all the experience of each other to find what actually works on our own machines.

@deckingman

Certainly I never took your test or your post as a slag on metal/steel nozzles, simply realizing that I am not necessarily using the best nozzle for my current printing needs.

When I first got into 3D printing with my Creality CR10S, I frequented its reddit sub. Over time the answer being shared around bothered me because every problem can't be "under extrusion".

Since I converted my now three printers two Duet board and started participating in this forum, I have learned so much, especially volumetric flow rates and their place in printing. Focusing on nozzle pressure made so much sense to me.

With this information that you have provided compliments that info. I still don't know exactly how the correlate, but if a certain amount of volume pressure in the nozzle is needed to maintain the quality of print, then exact nozzle temperature would need to be a highlighted aspect of that.

@zapta These nozzles look great. I will certainly look into these.

@deckingman

Great work. Since I joined the Duet community at the start of the year I have learned so much. But I always felt like there were chunks of information missing.

The point of "we know what makes a print work, and we use it, but we might not know why it works" comment is so true. Seeing unexpected results comes from these chunks of missing information.

I have been using A2 machine steel nozzles exclusively for over a year. Not because I print with abrasive materials, but because I figured they were more durable, and I could replace them less. I never really put temperature into the equation. I knew that hardened steel is less heat conductive, and I have tended to use higher temperatures because of this. But seeing your results as certainly opened my eyes wide, and I am going to go back to using high quality brass nozzles.

But on top of that, it makes me think greatly about the impact of cooling near the nozzle. Maybe the cooling ducts that are popular are thought to be great, but over doing their job and causing heat loss in unexpected ways.

It opens up a new direction of thought when thinking of some of the consistency issues I have been having.

@GT1Za said in G29 or G32:

@fcwilt please can you show me what your bed.g file looks like and the macro?

I wouldn’t mind seeing it as well. I have switched to independent Zs and am using a g32 before my g29 with mixed results.

What problems are you encountering?

There is also an ender 3 pro guide available too. I based my CR10S, Ender 5, and Ender 5 Plus off of that one.

@Argo

You and I are experiencing the same thing, with the same brand (and model) of printer. Have you printed anything else? Like a simple box. Something with a flat surface. I print a lot of simple boxes for board games. The tend to have a number of flat solid layers. Picture a box with a open top, and solid bottom.

My layers tend to have this double line, gap, double line, gap. Just like your right hand square. I am starting to think it is a mechanical problem with Creality printers. I have three of them and this patters happens on them all. It isnt on every part, or in every area. I think a lot of it is based on the BL Touch in conjunction with a backlash or mechanical shifting of things in the X-Axis or Y-Axis.

I am currently printing a fairly intricate player box for the board game Scythe. When it is done, I will post a picture of its flat surfaces.

Keep me in the loop as to your findings as I am working through various solutions myself.

I use a very tight setting. Just enought to safely clear the bed. That way your auto bed comp doesn't take for ever.

I find the same thing on my E5Plus. Even thought I do a fairly long and detailed bed process, I still find that I am having to babystep my way out of a disaster with most prints. Or worse, have to adjust the bed knobs. My regular ender5 and the CR10S (all running duets) don't seem to have this problem on such a consistent basis.

I even switched the setup to independant z motors and perform a G32, and still find I have to watch the first layer and make sure the filament goes down properly.

I perform a G28 to start, then a G32 to level the separate z axis, then do a G29 for the mesh. Still have issues. So either the G32 undoes itself, or it needs to be done after the G29...which does not make any sense.

Dumb oversight. I have been using the same parameters for the probe offset, but completely ignored the fact that I just changed this printer from a Microswiss hotend to and E3D Volcano. Y offset was not correct.