As mentioned in another thread, I recently received the pro version of this printer, yesterday in fact. I know Irv has 1 on order too, so I thought I would jot down some initial observations & impressions (please note, I wrote these down as I observed or thought of them, so no particular order of importance is implied): [LIST=1]
Just completed printing the money cat model that came with the printer. It’s the same 1 I tried to print from the SD card, but this time I printed it from Cura on my Surface Tablet. That worked. Really not sure what’s going on with the SD card issue. Will be interesting to see if Irv runs into it.
That is a valuable document you are creating for anyone else that buys one. Like me perhaps. It will be interesting to see in the future how much the “out for sale” model will vary.
So today I addressed the task of extruder calibration. This proved to be problematic. Just like the creator of this video ([U]JGMaker Artist-D IDEX 3D Printer: Deconstructed! - YouTube) said, the firmware only has 1 setting for extruder steps/mm. It appears to apply to both extruders. Of course, manufacturing tolerances make it highly unlikely that both extruders are identical, so their steps/mm won’t be the same. I thought about this, trying to figure a way around it. I decided, since the real issue is how much filament comes out of the nozzle in a given timeframe, that I could use Flow Rate, since it can be set separately for each extruder.
After half a dozen trial extrusions, tt turned out the Flow Rate values for the 2 extruders are quite different: 118% for the left 1 & 106% for the right. Fortunately, unlike the creator of the video, my printer seems to have fairly consistent extrusion. His didn’t, giving him different results each time, leading him to give up on reviewing the printer. To be fair, he was reviewing a beta version of the printer. JGMaker may have addressed that issue by the time they released the printer to production.
In the process of testing the extrusion rates, I ran into another issue: how exactly does 1 tell Marlin which extruder to use for any given command? I searched online but didn’t really find anything. Then I thought, “what if I take a really simply model, like the levelling squares I use to level printbeds, & assign 1 copy to the left extruder, and another to the right?”. I did that, then sliced the models & saved the gcode. Upon editing the gcode file it because obvious: T0 selects the left extruder & T1 selects the right.
I don’t mean that T0 or T1 is added to other gcode commands. T0 is a command in & of itself or, rather, T is a command & 0, 1, 2, etc. are parameters to select specific extruders. Once an extruder is selected, then all following commands apply to that extruder. For example: a T0 command, following by G1 X50 would move the left extruder to the 50mm location. A T1 followed by a G1 X50 would move the right extruder. I don’t know, but I kind of wonder of the T command stands for “Tool”.
It’s very handy to know this info when using Pronterface
That was a clever way of finding out find the command to select the extruder. You must be ready to print. Good luck.
Another thing I found relates to 2-color printing on the same model. It’s pretty easy to damage the printer by not using the correct mode. In the menu system there is a button called X Mode. It brings up a page with 4 options: Full Control, Auto-park, Mirror, & Duplicate. If someone has the printer in Full Control mode (the default) and tries to print a 2-color model, it’s almost certain that the 2nd extruder to start printing will crash into the 1st. Trust me, I know. The secret is simple: put the printer into Auto-park mode. When the 1st extruder is finished it’s work on a layer it will move to the brush pocket at the edge of the printer before the 2nd extruder starts it work on that layer.
I’ve only done 1 2-color print, a very simple 1. It’s a top & bottom model, 1 extruder printing the entire lower portion before the other extruder prints the entire upper part. I do not yet know what happens if there are 2 colors on the same layer: i.e. does 1 extruder print all of its part of the layer and auto-park before the 2nd extruder starts, or do they go back & forth on a layer, following the path as dictated by the slicer?
The left photo shows the issue I’m having with some roughness on the top surface. Look closely at the right photo, where the colors meet, & you will see a slight gap between the colors.
The removeable printbed surface is that black, textured stuff that makes it really hard to remove finished prints. And, if the nozzle is too close to the bed the really thin layer of filament is almost impossible to remove. Magigoo really helps, but it’s still a pain. I wonder if using the bed unheated would help?
It seems logical if a heated bed is used to increase adhesion.
Lowering bed temp to 40C has helped with releasing prints, even with PETG.
Did another 2-color print today. Another top/bottom print, bottom yellow, top red. The red is lettering.
Oh, & printing from SD card started working; don’t know why.
There is an evil spirit in my printer too.
This printer comes with 2 brush pockets. The idea is they’re parking places for the nozzles when not printing. The brass bristle brushes are supposed to clean oozing filament from the nozzles. It’s a mixed blessing. The issue is that when a print is about to start, the printer tries to home the extruder assemblies, even before the nozzles are hot again. This has led to a few times where 1 of the extruders ‘grinds’ against the drive belt because it can’t pull the extruder out of the brass brush – because it’s glued to the brush by the oozed filament. I’ve taken to manually moving the extruders off the brush once they’ve been wiped clean. That, or preheating the nozzle(s) before even starting the print, so the oozed filament will be soft enough to let the extruder move.
I’ve also found the brushes can build up with oozed filament fairly quickly. Removing the all-metal brush(es) from their plastic holder, grabbing them with pliers, & heating the oozed filament with a heat gun makes it possible to use a 2nd set of pliers to pull out 90% of the oozed filament.
I bet there will be a lot of things to learn about this printer even if it works well.
Discovered something pretty cool today. ! of the issues with dual extruder printers is getting the printer to switch extruders when printing models that weren’t designed for multi-extruder printers.
I searched for ways of doing this in Cura; perhaps an extension, but what I found is perhaps even better: [U]How to change extruder during printing in Cura with Ultimaker 3 - YouTube.
I guess I’m old and certifiably brain dead but I didn’t get the message.
@Irv_Shapiro, I have a suggestion for you re: the Artist-D printer. On mine, the Z limit switch adjust screw was a little misaligned from the switch itself. Rather than try to bend the springy metal piece that triggers the switch, I recommend screwing an M4 nut onto the adjustment screw so it is flush with the bottom of the screw & then crazy glue it in place. That will create a much larger triggering surface, so it won’t miss the metal trigger.
Are you sure you are in the right topic?
Absolutely. Irv has the same printer on order, so my suggestion relates to something he can do to it that might avoid a problem.
Ran into a really vexxing issue today. I successfully installed updated firmware – v2.3.3. On gitHub it warns that it’s necessary to recalibrate the printer after a firmware upgrade. OK fine. I’ll start with the extruders.
Problem is, I could not get accurate, nor repeatable results. Gross underextrusion. I mean, like 25mm extruded when I asked for 100mm. I played with the extruder steps/mm in the Settings/Motor menu. Very inconsistent results.
I went back to the 184.108.40.206 firmware. Same result. Something is very fishy here.
So, I disassembled the left extruder completely. What I found is a little disheartening. The gear wheel on the extruder motor simply presses the filament up against the inside of the hole the filament passes through into the nozzle. There isn’t even a grooved idler wheel. I’m quite concerned that these extruders are really subrate, and I’m not sure what can be done about it, if anything.
@Irv_Shapiro, I would be very interested in your views.
I’m surprised about this design. I recall one reviewer (I forget who it was) also having trouble calibrating the extruders. Do you have any pictures of the disassembled extruder? Do you think it would be possible to replace the extruders with an aftermarket one?
Lastly, have you contacted the manufacturer? I’d bet they have an upgraded replacement.
Thanks for your insights!
No pictures. I was so concentrated on remembering the exact order of disassembly (so I could reassemble ) I decided not to take photos. I think it turned out to be the right choice. I’m not sure how easy it would be to replace the extruders. It’s a pretty cramped assembly. I haven’t contacted JG Maker. Given that this is a brand new model I’m skeptical that there would be any replacement extruders yet. I am hopeful that JG Maker, or some 3rd party, might come up with a better extruder.