XL enclosure discussion and new issue....
Okay everyone thought I would start this thread for discussion and fixes. As many of you know I have been working and testing my enclosure for sometime now. I have recently completed closing it in pretty air tight so the temp will climb to about 52C and hold.
The issue is that now anything over 45-46 C the filament drags in the long PTFE tubes and the friction seems to stop or hinder the extrusion process. This is with ASA. The higher the temp the faster this happens.
There are no issues with PLA or lower enclosure temp filament.
I have tried both Nextruders and get the same result. At higher temps the higher temp filament stops wanting to feed. So what happens is the machine continues to print without any filament feeding into the nozzle.
If you look at the pic below you will see at some point the filament cannot be pulled through the long PTFE tubbing. The feed wheel just spins when it can't pull the filament through.
So what is the cure for this issue?
1. Use larger PTFE tubing between the filament sensor and Nextruders. Go from 2mm id to 3mm id ?
2. Don't use any PTFE tubing except at the Nextruders and the filament sensor.
I hate to tighten the feed gear as they have been working just fine.
You can see where the feed wheel just keeps spinning on the filament because it can't pull it through the long tubbing.
RE: XL enclosure discussion and new issue....
There are special low friction PTFE tubes available. But they are quite expensive.
https://www.amazon.de/Capricorn-Ultra-Friction-Bowden-1-75mm/dp/B07TXZJRTQ
I tried to change this tubes (factory installed) to a clear version, as I wanted to see what is happening inside the tube. But I have to change back to the original tubes. This was a bowden style extruder.
I have also seen YT videos where they apply PTFE dry grease inside the tubes.
RE: XL enclosure discussion and new issue....
Ok so this morning I am trying this to do a test. I removed the stock tube which had developed a kink where the wire tie held it at the base. This kink probably didn't help.
I put a section between the sensor and the first orange tube holder. Then I just installed some 25mm sections in the rest of the holders. I want to see if this alleviates some of the friction to make the filiment easier to pull. I will also be able to see what the filiment does outside the original PTFE tubing.
I have some of the low friction tubing, and some 3mm id tubing on the way to try that.
If these attempts do not work I will start thinking having the filament enter through the top of the Enclosure.
A pic of the kink that was under the wire tie. Both Nextruders have this kink.
RE: XL enclosure discussion and new issue....
This is what I am trying this morning I am hoping the filament doesn't kink at the little sections.
RE: XL enclosure discussion and new issue....
I will say there is a lot of stress on the filament watching the XL print without the tubing. The head has to travel a good distance front to back and left to right. Especially on a large print or a full print bed with parts.
By watching the filament I can see how there would be binding inside the small ID PTFE. I would think 3mm ID tubing or the low friction tubing would solve the problem.
RE: XL enclosure discussion and new issue....
That test did not work out!! So I reinstalled the original PTFE tube and keeping the temp between 42C-45C.
I am 2 hours into the same print that failed earlier and all is good so far.
ASA filament
Nozzle temp 250C
Bed temp 105C
Enclosure temp 42C-45C
I
RE: XL enclosure discussion and new issue....
So the filement is getting to hot and melting in the tubes?
I wonder if the enclosure needs vent holes like the Prusa prototype has?
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So the filement is getting to hot and melting in the tubes?
I wonder if the enclosure needs vent holes like the Prusa prototype has?
No it is not melting in the tubes. It looks like due to the higher heat in the enclosure there is more expansion. With such tight tolerances in the tubes that is causing the binding especially around some of the tighter corners, where the wire ties are behind the docking area and where the filament goes into the Nextruders. It is more the PTFE tubes then the filament. Apparently with the long run of PTFE tubes the heat is changing the shape of the tubes just enough to cause binding in the tubes.
45C and below there are no issues. Above that the binding starts.
RE: XL enclosure discussion and new issue....
I ran another test with ASA and different temps. The 2 over 45C (50C-52C) failed due to filament binding in the tubes. The last one at 42C-45C printed perfectly.
This is the good print that was printed at 42C-45C. The ASA filament ran smoothly though the PTFE tubes.
RE: XL enclosure discussion and new issue....
Here is a pic of one of the fails due to filament binding. As I mentioned earlier this only happens with hi temp filament like ASA with enclosure temps 46C +. There is no issues with sub 46C prints of any filament.
I saved this print and you can see where the filament binding starts and it progressively gets worse till there is no filament flow. The printer will continue printing without filament flow.
RE:
So the filement is getting to hot and melting in the tubes?
I wonder if the enclosure needs vent holes like the Prusa prototype has?
I can regulate the temp just by sliding the upper front acrylic piece up or down as needed. I I have about 13cm of adjustment.
You can see where I have lowered the front about 7cm to keep the temp between 42C and 45C.
RE: XL enclosure discussion and new issue....
Still going strong.
This is a 8+ hour print and we are 7 hours into the print in ASA.
RE: XL enclosure discussion and new issue....
Well then... just get new tubes with a higher clearance and loosen the thight spots? They are cheap so why bother with a temperature-dependance?
RE: XL enclosure discussion and new issue....
Well then... just get new tubes with a higher clearance and loosen the thight spots? They are cheap so why bother with a temperature-dependance?
As mentioned above I have new tubes on order.
RE: XL enclosure discussion and new issue....
So as part of getting my MMU2 to run as flawlessly as possible, and having ran into having the same kinds of binding issue on the MMU2, I switched out to 0.3MM ID PTFE feeders from my gravity rack and pinion spool rewinders to the PC4 mod plate I did no on the back of the MMU2, which did indeed cure the problem, initially. The caveat is the PTFE tube walls are SO thin that they are quite susceptible to kinking, and once they do the binding issue is back with a vengeance. I found I could typically go 6-7 months if I was super careful to be aware of the tubes at all times when changing spools in the autowinders, detaching them from the MMU for cleaning, etc, but invariably I’d forget at some point and would kink them up. While waiting for the 5 head XL to finally ship before I go on social security, I figured I may as well upgrade the MK3S(half plus) to a MK4 and pick up the MMU2-3 kit upgrade as the MMU2 had so many hours on it at this point that it was starting to get dodgy as well.
That was before Prusa stopped shipping the MMU2-3 kits for the MK4 which I’m still waiting on and havne’t upgraded the MK3 > MK4 as 90+% of my stuff uses the MMU2 if nothing else for parts labeling. So that upgrade is DOA until the MMU3 for MK4 finally ships. Since I’d’ been having more binding issues due to more frequent cleanings etc on the MMU2, I figured I should swap out all the PTFE from the spool winders to the MMU2 just to get it back up to snuff while I waited for both the XL and the MMU3 for the (as yet unused) MK4 upgrade kit.
Being as I was nearly out of 0.3ID PTFE, this time around I tried to locate 0.25MMID PTFE, with the thought process being it’d still be better than 0.2 for the binding issue but that extra half MM of wall thickness might make the stuff more durable and less kink prone just due to the necessary service stuff that just occurs. It proved more difficult to find than I’d have thought, as while there’s boatloads of 0.2MMID stuff and somewhat less of 0.3MM ID stuff, there’s not a lot of decent sources for 0.25mm, particularly in length. I ended up having to settle for 6’ chunks of the stuff, and the packaging left a LOT to be desired. This stuff was wound so tightly it was close to kinked right out of the box. Some coaxing and straightening with light applications of a heat gun has helped, and I’m just now redoing the silicone modified nyloc job on the bed before I redo the live Z. Hopefully that’ll cure the binding issue for the MMU2 until the upgrade kit gets here and will be reused on the MMU3. It does seem less kink prone than the 0.3MM stuff was though.
RE: XL enclosure discussion and new issue....
So as part of getting my MMU2 to run as flawlessly as possible, and having ran into having the same kinds of binding issue on the MMU2, I switched out to 0.3MM ID PTFE feeders from my gravity rack and pinion spool rewinders to the PC4 mod plate I did no on the back of the MMU2, which did indeed cure the problem, initially. The caveat is the PTFE tube walls are SO thin that they are quite susceptible to kinking, and once they do the binding issue is back with a vengeance. I found I could typically go 6-7 months if I was super careful to be aware of the tubes at all times when changing spools in the autowinders, detaching them from the MMU for cleaning, etc, but invariably I’d forget at some point and would kink them up. While waiting for the 5 head XL to finally ship before I go on social security, I figured I may as well upgrade the MK3S(half plus) to a MK4 and pick up the MMU2-3 kit upgrade as the MMU2 had so many hours on it at this point that it was starting to get dodgy as well.
That was before Prusa stopped shipping the MMU2-3 kits for the MK4 which I’m still waiting on and havne’t upgraded the MK3 > MK4 as 90+% of my stuff uses the MMU2 if nothing else for parts labeling. So that upgrade is DOA until the MMU3 for MK4 finally ships. Since I’d’ been having more binding issues due to more frequent cleanings etc on the MMU2, I figured I should swap out all the PTFE from the spool winders to the MMU2 just to get it back up to snuff while I waited for both the XL and the MMU3 for the (as yet unused) MK4 upgrade kit.
Being as I was nearly out of 0.3ID PTFE, this time around I tried to locate 0.25MMID PTFE, with the thought process being it’d still be better than 0.2 for the binding issue but that extra half MM of wall thickness might make the stuff more durable and less kink prone just due to the necessary service stuff that just occurs. It proved more difficult to find than I’d have thought, as while there’s boatloads of 0.2MMID stuff and somewhat less of 0.3MM ID stuff, there’s not a lot of decent sources for 0.25mm, particularly in length. I ended up having to settle for 6’ chunks of the stuff, and the packaging left a LOT to be desired. This stuff was wound so tightly it was close to kinked right out of the box. Some coaxing and straightening with light applications of a heat gun has helped, and I’m just now redoing the silicone modified nyloc job on the bed before I redo the live Z. Hopefully that’ll cure the binding issue for the MMU2 until the upgrade kit gets here and will be reused on the MMU3. It does seem less kink prone than the 0.3MM stuff was though.
Let me know how he 2.5mm ID PTFE works. I am up to 875 hrs on my XL and this had really been the only issue so far. I still have the 3mm ID PTFE installed right know and it has worked great so far. I think when I decided to swap out the .6mm nozzles for .4 mm nozzles I am going to put new tubes on the printer at the same time
RE: XL enclosure discussion and new issue....
Will do. I found out just before the XLshipped jump from 0.6 to 0.4 a bit odd (particularly since I’d spent a few months trying to round up enough obxidian 0.6’s for the xl (still one short) and now that it’s shipped getting wind I’m getting 0.4’s is a bit perplexing as 5 Obxidian’s of an flavor is a fair chunk of cash to tie up. So hearing you making the jump from 0.6 to 0.4 a bit of a jolt. I’d moved to a 0.6 obxidian on my I3 and have really liked moving to 0.6 full time as besides the reduction in print time, the taller layers 0.3 give better adhesion etc for mechanical parts.
So curious as to why you’re hopping down from 0.6 to 0.4? Is it the stringing issue?
RE: XL enclosure discussion and new issue....
Will do. I found out just before the XLshipped jump from 0.6 to 0.4 a bit odd (particularly since I’d spent a few months trying to round up enough obxidian 0.6’s for the xl (still one short) and now that it’s shipped getting wind I’m getting 0.4’s is a bit perplexing as 5 Obxidian’s of an flavor is a fair chunk of cash to tie up. So hearing you making the jump from 0.6 to 0.4 a bit of a jolt. I’d moved to a 0.6 obxidian on my I3 and have really liked moving to 0.6 full time as besides the reduction in print time, the taller layers 0.3 give better adhesion etc for mechanical parts.
So curious as to why you’re hopping down from 0.6 to 0.4? Is it the stringing issue?
The .60 nozzle has worked out well for the enclosure and enclosure accessory parts. I have some projects coming up that require a lot more detail so the .40 will be needed. I am also curious to see the difference in printing between the two on the XL
RE: XL enclosure discussion and new issue....
I'm chasing this issue as well in an enclosure, but I'm thinking its heat creep. I can consistently get PLA to heat creep jam at above 43C heat break thermistor temperature. And PETG to heat creep jam above 52C heat break thermistor temperature. Although that varies a bit down to 45C depending on enclosure temperature.
Even with an open top and doors (but sides installed), its right on the edge printing a full bed PETG print during low flow fill areas.
No luck with fan shrouds trying to pull in air further away from the build plate. Thermal paste helped slightly, but not enough to run the enclosure closed at the start. Once the build is 25mm or so off the plate, its better. I also thought it was the PTFE tubes initially, and tried both 3mm ID and 2mm ID tubes but no luck.
Machining an aluminum stack on heat sink to place under the fan to try and gain some heat rejection from the heat break. But it will be a balance of how to tie it in to keep the strain gauge working correctly for nozzle touch off. I think that side of the tool changer extruder wants some support, as the fan shroud is tied into the tool changer and then spans to the back bolt on the heat break to allow the nozzle section to still flex upwards.
RE:
Hello again everyone. I have had some ask what accessories I have added to the enclosure. So I compiled a list with photos for you. I did fairly extensive testing over the past few months on all the accessories and I am happy with all the choices.
First thing of note here all these choices were researched for my use of the XL printer. Your choices might be different. This is not the ultimate setup but it does work for me. Another note I don't have access to these accessories locally so I ordered them all. All but one came from Amazon. $21.00
First pic:
1.Amazons Basic 500wt ceramic heater. It is small simple and fits with the printed mount on the right side lower panel.
2. Below the heater I installed a Nispira 3-in-1 True HEPA Carbon air intake filter. The housing was printed. The filters come in a 4 pack. $24.00
Pic 2:
1. WYZE Cam v3 1080P Wired Indoor/Outdoor Home Security Camera. Mount was printed $76.00
2. Under the camera a SMARTRO SC42 Professional Digital Hygrometer Indoor Thermometer Room Humidity Gauge $16.00
Pic 3:
1. AC Infinity AXIAL 8038, Quiet Muffin Fan, 120V AC 80mm x 38mm for exhaust baffling. $18.00
Under the fan.
2. AC Infinity, Fan Speed Controller for 100 to 125V AC Axial Muffin Cooling Fan. $18.00
Pic 4:
1. Top right: DIGITEN DTC151 Temperature Controller Plug-in Thermostat Cooling Heating Temperature Controller 15 amp. $37.00 (For heater)
2. 2-SUNLU Filament Dryer with Fan, Upgraded Fast Heating 3D Printer Filament Dryer Box, Keep Filament Dry During 3D Printing, PLA PETG ABS TPU Nylon ASA Filament Dehydrator Storage Box, FilaDryer S2 Black $70 x 2 =$140.00
3. CRST 12 Outlets Heavy Duty Power Strip Surge Protector with Individual Switches, Metal Mountable Power Strip with Cord Manager, 9FT, 1020J, 15A/1875W. $53.00
4. SURAIELEC Watt Meter, Plug-in Socket Power Meter, Auto Cost Calculator, Backlit Large Display, Overload Protection, Kilowatt Wattage Voltage AMP Tester, Electricity Usage Electrical Energy Monitor. (For air scrubber.) $12.00
Pic 5:
Kasa Smart Plug HS103P4, Smart Home Wi-Fi Outlet Works with Alexa, Echo, Google Home & IFTTT, No Hub Required, Remote Control, 15 Amp, UL Certified, 4-Pack, White $ 6.00 each (to turn system off remotely.
