[Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

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NebNorse
Posts: 6
Joined: Fri Apr 12, 2019 6:28 pm

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by NebNorse » Mon Aug 05, 2019 6:35 am

I wonder if I am having a heat creep problem with the v2 duel also. Only seems to happen when I print nGen or PLA.

I attached a pic of how the print last night went.

For some reason, the duel head ran for about 3 weeks with no problem, then this weekend it has just been giving me fits. Last night I got one good print, then back to the same problem of the filament not feeding.

Could humidity also be contributing to this? I do dry my plastic, but living in Nebraska... well we have humidity. :D
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20190805_063529.jpg

JoeBowler300
Posts: 116
Joined: Thu Apr 28, 2016 12:20 am

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by JoeBowler300 » Wed Aug 07, 2019 7:37 am

Very possible! Definitely with PLA. The picture you uploaded looks like nGen filament correct? How long into the print? What's your printing speed? Are you printing with a 2nd filament in the other extruder? If not I suggest getting the Aerostruder print head with a silicone soc for single filament prints, that print head is flawless!

I can print PLA in my dual extruder for a long time as long as I keep pushing filament through. Once I start printing with 2 filaments it seems that the heat creep gets me on my PLA! The second filament (Ninjaflex) prints at a much hotter temperature (225C) and while its printing the extruder with the PLA cools down a bit (175C) while its on standby while the other filament prints, then heats back up to my PLA printing temperature when its time to print the PLA again. Eventually the heat creep gets to it and it fails. About 2 hours into the print for me, the first hour is PLA, after the first hour it kicks into printing the other filament. However I was printing the PLA at a high temp like 225C, since I throttled it down to 185C I'm beginning to able to get successful dual extrusion prints with PLA and Ninjaflex filament. I also replaced that weak ass fan with a Noctua fan

NebNorse
Posts: 6
Joined: Fri Apr 12, 2019 6:28 pm

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by NebNorse » Thu Aug 08, 2019 8:46 pm

Pictured is PLA.

Just using the 1 extruder. Number 2 is heated to default stand by temp. I have been using the default temps in Cura 3.6.13

I have found that 40mm/s is a good speed for me. It seems to allow the finer details to show through on some of my other prints and I have just gotten into the habit of that speed... Could I be printing too slow?

Normally fails around the 1.5 hr to 2 hr mark. Yesterday it printed fine. Today, it failed 3 hrs into the print.

Just seems to come and go.

JoeBowler300
Posts: 116
Joined: Thu Apr 28, 2016 12:20 am

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by JoeBowler300 » Wed Aug 14, 2019 12:08 am

I can confirm that the 1.5 to 2 hour mark is about the time my PLA prints would fail on the Dual Extruder v3. I doubt turning up your speed from 40mm/s will make any real difference, I use the default profile's speed setting of 60mm/s and still experience failures around the same time you do. Both extruder's share the same heat sink (a poor design IMO) so what you should do is try making a dummy profile for the other extruder you're not using. I know there's a No Material profile but.... I'm not quite sure what that profile does cause the printing temperature is set to 240C. Though I guess that doesn't really matter cause the unused extruder associated with that profile should be in standby which is 150C. But why heat it up to 150C (302F) if you don't have too! Especially when cooling is a problem!?

Turn on your printer and look at the LCD panel and see what the temperature is at. Set it to that or maybe 5C higher cause if you set it too low it will never cool down to reach your target temperature, plus it will heat up to the target temperature quickly; especially if it only has to go up only 5C or less. It is possible to make a profile with 0 degrees but I don't recommend it, it will take 2 or 3 minutes to timeout and move on.

Know that some settings on one extruder will affect the value on the other extruder. Extruder1 + Extruder2 / 2. For example, the Build Plate Temperature is a value shared between extruders; a change on one side will affect the value on the other side. Layer Height is also a good example. So be sure to make your dummy profile with the same value of the filament you'll be printing with for the settings that are shared.

In quick summary in the dummy profile I would set all the printing temperatures to about 30C including the standby temperature. Here's a good link that explains what those temperature settings mean. https://ultimaker.com/en/resources/52837-material

I get successful PLA prints on the v3 Dual Extruder with a better quality PLA such as that from Hatchbox. Some PLAs are just too soft (mostly no name brand) and absolutely nothing can make those work on the v3 Dual Extruder, and I've tried many things to improve the cooling to no avail.

b-morgan
Posts: 315
Joined: Fri Aug 11, 2017 8:53 am

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by b-morgan » Thu Aug 15, 2019 10:35 am

I'm confused. I think NebNorse is talking about heat creep on the Dual V2 and JoeBowler300 is talking about the Dual V3.

While both the V2 and the V3 can suffer from heat creep, the reasons and possible solutions are very different. On the V2, the two extruders are separate each with its own (IMO, inadequate) cooling fan. One solution is documented in viewtopic.php?f=36&t=4348.

On the V3, the shared heatsink with, IMO, poorly engineered cooling flow, has a solution that works for me at https://www.thingiverse.com/thing:3213878. I was able to get the stock fan to attach with some careful rerouting of the existing wiring. There are also higher CFM 40mm fans that can be used if necessary.

NebNorse
Posts: 6
Joined: Fri Apr 12, 2019 6:28 pm

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by NebNorse » Thu Aug 15, 2019 1:28 pm

I will print those out, get a few fans and give that a try!

I did get the PLA to print. Dried it out for about 2 days, cooled the printer and it did work. The nGen however is still giving me fits, so I will deferentially try this.

JoeBowler300
Posts: 116
Joined: Thu Apr 28, 2016 12:20 am

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by JoeBowler300 » Thu Aug 15, 2019 7:47 pm

Well hell! I guess I didn’t notice that. :o

NebNorse
Posts: 6
Joined: Fri Apr 12, 2019 6:28 pm

Re: [Dual Extruder v3] Filament Stops Feeding, Ruins Print, Can't get out Easily

Post by NebNorse » Sun Sep 08, 2019 8:14 pm

So after extensive testing... more than you would want to know. I found my suspected problem and it seems solution.

The dehydrator I was using was getting too hot for the material. If I dry them at a lower temp for 12 hrs, it prints much much better.

I did install the heat sink coolers and that really did help a LOT! Thank you for that tip!

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