Dual Extrusion - Multiple Questiuons

[MTG 8]

Hey,

 

1. I have to use an other power supply for two 35W heaters, right? Any suggestions which one I could use or where to get the plug?
2. What are the differences between the 35W and the 25W heaters? (just curious, I guess they get the same voltage?)
3. Are there heaters with more than 35 W that I can use? I mean, if i have to get a new power supply anyway, I could also use two 50W (if somesthing like that exists)
4. I'm using the thinkergnome firmware for dual extrusion. Is there any possibility to adjust the z-heights seperately for every extruder?
5. Is it possible to lower the 5V fan speed via software, or do I have to use a resistor?

 

Thank you for your help.

 

 

 

Edited October 8, 2019 by MTG

[conny_g 251]

46 minutes ago, MTG said:

Hey,

I just finished my prototype printhead for the UM2+ Extended. But I have some work to do:

I used two 25 W Heaters for the nozzle. It turns out my printhead cooling is pretty good. The nozzle barely reaches 250°, I have to lower the fan speed for not getting the heater error.

 

1. I have to use an other power supply for two 35W heaters, right? Any suggestions which one I could use or where to get the plug?

 

Tinkergnome has added a power budget feature that allows to limit / prioritize the power usage between bed and the heads. With that I think it's not necessary to change the power supply.

But it's also possible to upgrade the power supply. I have done that and I have used this: https://de.aliexpress.com/item/Top-Qualit-t-24-V-15A-3D-Prnter-Ultimaker2-Netzteil-F-r-Ultimaker-2-UM2-Erweiterte/32832288123.html?spm=a2g0s.9042311.0.0.77204c4dDxlATR

 

Quote

1. What are the differences between the 35W and the 25W heaters? (just curious, I guess they get the same voltage?)

 

LOL, the 35W heater has 10W more power. SCNR. It has lower resistance, draws higher current so it heats up more. It gets the same voltage.

 

Quote

1. Are there heaters with more than 35 W that I can use? I mean, if i have to get a new power supply anyway, I could also use two 50W (if somesthing like that exists)

 

Yes, there are 50W heaters, I have replaced my heaters with these and the heads heat up really quickly.

https://3dsolex.com/product/50w-heater-um2/

 

Quote

1. I'm using the thinkergnome firmware for dual extrusion. Is there any possibility to adjust the z-heights seperately for every extruder?

 

Yes, it has a z offset adjust feature.

 

Quote

1. Is it possible to lower the 5V fan speed via software, or do I have to use a resistor?

 

Here

https://github.com/Ultimaker/Ultimaker2/blob/master/1091_Main_board_v2.1.1_(x1)/Main Board V2.1.1.pdf

on page 5 you find the silk screen print of the board and see that the 5V fan is J34.

On page 9 in the circuit schemas you find that J34 is connected directly to 5V, there is no PWM regulation or anything.
 

 

Quote

Thank you for your help.

 

 

 

 

Edited March 19, 2019 by conny_g

[MTG 8]

Quote

Yes, it has a z offset adjust feature.

 

Okay, I found the usual "adjust buildplate". When I go to expert functions, there is also a feature called "adjust z position". I chose that and the i can adjust the buildplate. but only for one nozzle. Shouldn't that start the adjust position twice? Like one time for every nozzle? How am I supposed to get two values?

 

I know that I can adjust the x- and y-offsets in cura. But not z...

[conny_g 251]

This adjusts the z position of the currently active extruder.
So if you want to adjust it for the 2nd extruder, you need to activate it and then go to z adjust.

[gr5 2,167]

Note that tinker marlin allows you to control the power budget.  Tell the printer the budget is 175W and the bed is 150W and tell it what the wattage of your two nozzle heaters are and the printer will make sure you don't go over budget.

 

However there is a bug in power budget code and you need the absolute latest tinkerMarlin (well at least version 19.03).

 

[calinb 11]

You might be able to manually adjust the power budget too. Years ago I ran a water cooled Garcad hotend (the first water cooled hotend I ever saw) on my UMO. It had a 6 ohm heater that would reset my UMO, due to overload. Here's what I wrote to the developer at the time. This method worked and I assume that PID_MAX is still a Marlin "knob" that you can tweak, if you're willing to build your own Marlin code.

Quote

Looking through the Marlin Configuration.h file I found this:

#define PID_MAX 256 // limits current to nozzle while PID is active (see PID_FUNCTIONAL_RANGE below); 256=full current

If it truly limits current and the 0-256 range is linear (why it's not the expected 255 max, I have no idea), then a setting of 181 should deliver half-power.

 

 

[MTG 8]

22 hours ago, conny_g said:

This adjusts the z position of the currently active extruder.
So if you want to adjust it for the 2nd extruder, you need to activate it and then go to z adjust. 

 

So I just came back to this. The question I can't get behind is: how do I activate an specific extruder?

There is somethin like "Swap extruders" under "Advanced", but It shows the same Z-Value in home so I guess thats not how to do it...

 

[conny_g 251]

Yes, the swap extruders it is.

[tinkergnome 927]

On 3/19/2019 at 3:50 PM, MTG said:

I'm using the thinkergnome firmware for dual extrusion. Is there any possibility to adjust the z-heights seperately for every extruder?

 

Nope. There are no separate z-offset settings in the normal Marlin firmware. With this classic approach both nozzles have to be at the exact same height (if you want to use both at a time).

 

The firmware variant for Mark2 / magnetic tool changer got quite a few upgrades to handle both printheads separately, but this is a different topic.

[conny_g 251]

Ah. Then I was confusing the tinker version with the Mark 2 version.

[MTG 8]

6 hours ago, tinkergnome said:

 

Nope. There are no separate z-offset settings in the normal Marlin firmware. With this classic approach both nozzles have to be at the exact same height (if you want to use both at a time).

 

The firmware variant for Mark2 / magnetic tool changer got quite a few upgrades to handle both printheads separately, but this is a different topic.

 Oh that's too bad. Could be really useful in that firmware. Is it much work to add?

 

I guess I can't use the Mark 2 Firmware? I have a custom tool change script which I wanted to use over cura ...

[MTG 8]

18 hours ago, tinkergnome said:

 

Nope. There are no separate z-offset settings in the normal Marlin firmware. With this classic approach both nozzles have to be at the exact same height (if you want to use both at a time).

 

The firmware variant for Mark2 / magnetic tool changer got quite a few upgrades to handle both printheads separately, but this is a different topic. 

 

Just had a look in the current TinkerFW. I'm not very experienced in c++, but from what I have seen, the extruder_offset variable is the way to go. But it's made only for XY : // Extruder offset, only in XY plane

 

Think I have to add a EXTRUDER_OFFSET_Z.

 

Important might be the T command for toolchange. It seems like it's just adding the offset to the current positions in x and y. Therfore it has to be added in z, too.

 

Other thing is how to calibrate. I'm uising Octoprint, maybe I can just set the Offsets via M218 command that I don't have to program the gui...

 

Is the Mark2 firmware open source btw? Might be less work adding the custom tool change there..

[tinkergnome 927]

1 hour ago, MTG said:

Is the Mark2 firmware open source btw? Might be less work adding the custom tool change there.

 

the sources are here (branch "Mark2"):

https://github.com/TinkerGnome/Ultimaker2Marlin/tree/Mark2

 

You can put custom tool change scripts on the sd-card (only if those are short - RAM is very limited).

Folder name and file names are defined here:

https://github.com/TinkerGnome/Ultimaker2Marlin/blob/Mark2/Marlin/commandbuffer.cpp#L22

 

default processing is in CommandBuffer::processT0  resp. processT1

 

Good luck!

[MTG 8]

1 hour ago, tinkergnome said:

You can put custom tool change scripts on the sd-card (only if those are short - RAM is very limited).

Folder name and file names are defined here: 

https://github.com/TinkerGnome/Ultimaker2Marlin/blob/Mark2/Marlin/commandbuffer.cpp#L22

 

Thank you!

 

I made an directory "config" on the SD with "T0.gcode" and "T1.gcode". But when I try to change (via command line T0 or T1 and also under menu point "Change extruder") it won't take my custom script, it does execute the mark2 change script.

 

I also built the firmware on my own with " TCSDSCRIPT SDSUPPORT " in $MAKE (in package.sh), but no luck.

 

What am I missing?

[gr5 2,167]

Possibly you have to reboot your printer after inserting the SD card?

[MTG 8]

3 minutes ago, gr5 said:

Possibly you have to reboot your printer after inserting the SD card?

 

No, I just tried it again. Won't take my script..

Just the existence of the folder and the script should toggle the printer to use my code, right?

 

Just looked into the firmware, could also write it there, but the sdcard would be much better for me

[tinkergnome 927]

Don't add the "gcode" file extension. The file name should be a simple "T0" and "T1" - without any extension.

[MTG 8]

15 hours ago, tinkergnome said:

Don't add the "gcode" file extension. The file name should be a simple "T0" and "T1" - without any extension.

 

Just did this.

Good: It looks like it did something, it does not start the mark2 routine

Bad: It does some weid stuff which seems barely connected to my script. My T1 for example is the following:

 

G0 F6000 X220 Y215 
G0 Y223
G0 F1000 X218
G2 F4000 X184 Y219 I-19 J15.9
G0 F6000 Y215

 

So it should move to the right back corner, then move a few mms back, 2mm to the side and then do a circle. Then move a few mms to the front. All happens in the right back corner, where also is my lever shifting stop.

When I start it as gcode programm or when I insert them one by one into the console everything is fine.

But when I start the toolchange it first moves to the front right corner, then to the front left, does a weird circle, then moves to the back right corner, and then back to the front right.

I first thought it would have something to to with absolute positioning, so i did write G90 at the beginning of my files. It didnt change anything.

 

The movement is so weird, I don't even know what to do to fix this. From Soure Code it seems like it's just starting my script:

 

 if (t1)
    {
        processScript(t1);
        if (bRetract)
        {
            toolchange_retract(current_position[X_AXIS], current_position[Y_AXIS], toolchange_retractfeedrate[0]/60, 0);
        }
    }

Is it possible that it ignores settings like that the y-axis is inverted when the script is called from there? Did anyone use this feature yet and has made an own working toolchange script?

[tinkergnome 927]

There are some more things that are done in the changeExtruder function.

One candidate is move2heatup which depends on the stored Prime/wipe position and docking position.

I guess you can make some changes to the latter function and the you're almost there.

 

[MTG 8]

It's hard work, but I'm slowly making progress. I have one more Question regarding the toolchange retract:

 

• There is a toolchange retract in the tinker firmware and in cura. I'm using octoprint so no ultigcode here. Does it use the cura settings, the firmware settings or both? If both, can I just zero the cura setting to use the firmware only?
• I have the strange behavior, that every second layer is overextruded. Do you have any idea where this can come from? My assumption is that it's because of the tool change.
• Waht exactly is the "prime" value in toolchange retract option? If there is 1mm, does this extrude 1mm extra filament? Like when the setting is 16mm, does it retract 16mm and after that extrudes 17mm?

Thank you for your help

 

Edit: I don't want to lower the temp during extruder standby. Is it enough to set the standby temp as the same as print temp in cura? Or is there a fw setting?

Edited April 9, 2019 by MTG

[tinkergnome 927]

7 hours ago, MTG said:

There is a toolchange retract in the tinker firmware and in cura. I'm using octoprint so no ultigcode here. Does it use the cura settings, the firmware settings or both? If both, can I just zero the cura setting to use the firmware only?

 

It uses the firmware settings, or with other words: during a toolchange the firmware retracts the difference between a former normal retract (if present) and the configured toolchange retraction.

The Mark2 definition for Cura uses the same values for normal and toolchange retractions. I recommend to do it the same way.

 

7 hours ago, MTG said:

Waht exactly is the "prime" value in toolchange retract option? If there is 1mm, does this extrude 1mm extra filament? Like when the setting is 16mm, does it retract 16mm and after that extrudes 17mm?

 

That's exactly what it does. It's there to compensate for material that oozes out during standby times (some materials and nozzles tend to do this more than others...)
For normal things you can leave it at zero.

 

7 hours ago, MTG said:

I don't want to lower the temp during extruder standby. Is it enough to set the standby temp as the same as print temp in cura? Or is there a fw setting?

 

Firmware standby temperatures are disabled if the gcode file contains temperature commands for the inactive nozzle. I'm not sure if Cura inserts M104 gcodes, if the standby temperature is equal to the print temperature....? It's worth a try IMHO.