At my wits end with PETG

At my wits end with PETG Everyone says that PETG is sooooo easy to use. Well I at my wits end. I got 3 rolls of PETG from 3 different manufacturers and they all do the same thing. With each new roll I used a new hot end with a new nozzle and the same thing happens with each. The extruded PETG whips around after coming out of the nozzle and the loose end sticks to the nozzle either making a loop or a blob. I would think that the nozzle is clogged, but the whole hot end is new including the nozzle. I am using a 0.3 mm nozzle though the same thing has happened with a .4 mm nozzle. I tried using the PETG at 230°C, 235°C 240°C 245°C and 250°C. When I tried to print the Airtrippers Pocket Filament Reel Rollers from Thingiverse the perimeters seem to print fine but the infill just blobs up and I can not even get the first layer down. Does anybody know what is going on? Does anybody have any suggestions? Thanx in advanced. Stuart https://reprap.org/forum/read.php?262,633175,633175#msg-633175 Wed, 07 Oct 2026 12:46:45 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?262,633175,650416#msg-650416 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,650416#msg-650416

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JamesK

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DRTak
How did you verify that your thermistor was the correct temp? I cannot figure out how? Do you aim the IR thermometer at the heatbreak?

I wish I would have done that before I installed it with RTV silicone into the heaterblock. You are right. I should have attached the hotened thermistor to the heated bed. Then checked the hotend thermistor temp to that of the heatbed. That would have helped me. For now I can only assume that my hotened thermistor may be off by 10-30 deg cel]]> DRTak Printing Sat, 09 Apr 2016 17:26:33 -0400 https://reprap.org/forum/read.php?262,633175,647602#msg-647602 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,647602#msg-647602

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DRTak
How did you verify that your thermistor was the correct temp? I cannot figure out how? Do you aim the IR thermometer at the heatbreak?

I compared the thermistor readings against the K-type thermometer. I'm assuming that the K-type performs according to spec, which may be a bit of a leap, but what can you do. The hotend is too small to get reliable readings with the IR thermometer. The comparison I did was on the top surface of the glass bed, comparing the IR against the reading from the K-type. The IR thermometer appears to be the least reliable, but it's quick and convenient and gives ballpark measurements for motors and electronics.]]> JamesK Printing Sat, 02 Apr 2016 14:58:50 -0400 https://reprap.org/forum/read.php?262,633175,647600#msg-647600 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,647600#msg-647600 DRTak Printing Sat, 02 Apr 2016 14:54:17 -0400 https://reprap.org/forum/read.php?262,633175,647556#msg-647556 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,647556#msg-647556 JamesK Printing Sat, 02 Apr 2016 12:10:18 -0400 https://reprap.org/forum/read.php?262,633175,647553#msg-647553 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,647553#msg-647553
I bought a new hotend with a new different thermistor. I have no way of testing the settings for the thermistor. Its supposed to be a EPCOS 100K generic thermistor. But I do not know if its a 1k or 4.7k pullup. After various testing, I could not get the filament to stick to the bed. I figured out that the hotend was not hot enough. Also, I figured that the glass bed was not hot enough. So I cranked them both up higher. Now the filament sticks.

My new temps are 247 deg C for the hotend and 87 deg for the hotbed. I have tried 237, 238, 240 for the hotend with little success. I have also tried 73, 75, 77, and 80deg for the hotbed and no success. The only way I made it work was with the temps above of 247 hotend and 87 hotbed.

The hotbed is the correct temp because can check it with my IR thermomiter. But the hotened is covered by a silicon boot.]]> DRTak Printing Sat, 02 Apr 2016 12:00:35 -0400 https://reprap.org/forum/read.php?262,633175,646838#msg-646838 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,646838#msg-646838

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amigob
I constanly see that at the beginning and and if an extruded line I have to much filament.
So I was wondering are extruded amounts synced with the movement acceleration ?
So not only with speed.

Or should I match these movement accelerations with extrusion acceleration my self ?
I use Repetier

You might need to find the retraction rate settings. Adjust that so you do not get too much extruded filament after a print.]]> DRTak Printing Thu, 31 Mar 2016 11:17:55 -0400 https://reprap.org/forum/read.php?262,633175,645390#msg-645390 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,645390#msg-645390 So I was wondering are extruded amounts synced with the movement acceleration ?
So not only with speed.

Or should I match these movement accelerations with extrusion acceleration my self ?
I use Repetier]]> amigob Printing Mon, 28 Mar 2016 11:23:02 -0400 https://reprap.org/forum/read.php?262,633175,644858#msg-644858 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644858#msg-644858 after cool down it was already loose, :D]]> amigob Printing Sat, 26 Mar 2016 19:25:57 -0400 https://reprap.org/forum/read.php?262,633175,644833#msg-644833 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644833#msg-644833 So I am stuck with Real PETG filament
And the normal price ~80 dollars per kilo ????

I will make a Movie of loosening my prints now it is really ' amazing mike '::o]]> amigob Printing Sat, 26 Mar 2016 17:46:47 -0400 https://reprap.org/forum/read.php?262,633175,644829#msg-644829 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644829#msg-644829

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MrBaz
Using MakerGeeks PETG
60*C bed
250*C hotend

I have verified my temps with an IR temp gun - max 3* deviation.

Sticks just fine to clean glass mirror. I have to pry up the corners a little and work around the edges of large surface area prints with a razor blade to get them to loosen. Nothing worrisome so far.

Exactly. PETG likes glass.

My settingss:
Brand: Alchement
73*C bed
238*C hotend

Would not recommend Alchement brand. I was printing a 5hr print. And checked on it every 15min. Then got comfortable with it. Checked it again at the 4hr mark, there was a non uniform bump in the filament. This plugged the extruder. The gears were grinding the filament cuz it was stuck. I would say 1 hr ago it got stuck. So the nozzle was floating in the air now laying down filament.]]> DRTak Printing Sat, 26 Mar 2016 17:36:24 -0400 https://reprap.org/forum/read.php?262,633175,644810#msg-644810 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644810#msg-644810 60*C bed
250*C hotend

I have verified my temps with an IR temp gun - max 3* deviation.

Sticks just fine to clean glass mirror. I have to pry up the corners a little and work around the edges of large surface area prints with a razor blade to get them to loosen. Nothing worrisome so far.]]> MrBaz Printing Sat, 26 Mar 2016 16:48:47 -0400 https://reprap.org/forum/read.php?262,633175,644666#msg-644666 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644666#msg-644666

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amigob
I tried everything ( different heights, different temperatures ( PETG and bed ), different flow rates ), to get the PETG stick to the glass but it just didn't.
And really it doesn't stick at all.

So I gave up on that, I printed the x carrier, again last night, and really with the pray, it sticks extreme, and lifting the brim after cooldown pop and it is of.
I am so confident in this solution that I am going to try ABS now.

Well it might be your PETG you are using. When I have my z height to close to the printbed (ie around -.05 to -0.15), PETG gets smeared onto the heatbed. So much so that I peeled off parts of the tempered glass right off the glass itself. Therefore, I learned that it is more important to have it the correct height with less stickyness than too close. Also, after each print I use rubbing alcohol to clean the glass bed. This helps a lot.]]> DRTak Printing Sat, 26 Mar 2016 09:00:46 -0400 https://reprap.org/forum/read.php?262,633175,644571#msg-644571 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644571#msg-644571 And really it doesn't stick at all.

So I gave up on that, I printed the x carrier, again last night, and really with the pray, it sticks extreme, and lifting the brim after cooldown pop and it is of.
I am so confident in this solution that I am going to try ABS now.]]> amigob Printing Sat, 26 Mar 2016 04:22:46 -0400 https://reprap.org/forum/read.php?262,633175,644501#msg-644501 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644501#msg-644501

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amigob
I found a good solution for me for the first layer of PETG
- every thing sticks direly to the bed
- no strings any more on the first layer
- sticks very well

after cool down ( used 90 degrees bed )
first experience removing the finished product, couldn't get it loss :-{ even not with a pliers.
But lifting the brim with a knife and plop it was loss :-)

[attachment 75329 WP_20160325_005.jpg]

I sprayed the glass plate with 3DLAC spray

one disadvantage , cleaning the glass plate is messy.

I dont use any spray or glue etc. I print PETG directly to the glass bed. I cant get the print off wihtout using a paint scraper blade. You just have to make sure your z height is correct. Then for me make the first layer thick. 0.4mm for a 0.4mm nozzle. My bed is at 72deg C and its nice and sticky.]]> DRTak Printing Fri, 25 Mar 2016 18:51:30 -0400 https://reprap.org/forum/read.php?262,633175,644458#msg-644458 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,644458#msg-644458 - every thing sticks direly to the bed
- no strings any more on the first layer
- sticks very well

after cool down ( used 90 degrees bed )
first experience removing the finished product, couldn't get it loss :-{ even not with a pliers.
But lifting the brim with a knife and plop it was loss :-)

[attachment 75329 WP_20160325_005.jpg]

I sprayed the glass plate with 3DLAC spray

one disadvantage , cleaning the glass plate is messy.]]> amigob Printing Fri, 25 Mar 2016 17:02:20 -0400 https://reprap.org/forum/read.php?262,633175,642428#msg-642428 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,642428#msg-642428

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JamesK
The v6 only brings the ptfe to above the level of the heatsink. As long as the fan is running temperatures up there should be fine. The v6-lite takes the ptfe all the way to the nozzle junction and it will be subject to much higher temperatures. Like the one I was using.

Well the issue was I found that the Hotend fan was out. The wires disconnected from too much tension. So the heat creeped down into the heat barrel and melted the ptfe into the nozzle.]]> DRTak Printing Mon, 21 Mar 2016 09:15:58 -0400 https://reprap.org/forum/read.php?262,633175,642051#msg-642051 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,642051#msg-642051
[forums.reprap.org]]]> Tinchus Printing Sun, 20 Mar 2016 08:46:52 -0400 https://reprap.org/forum/read.php?262,633175,640995#msg-640995 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640995#msg-640995 JamesK Printing Thu, 17 Mar 2016 16:27:56 -0400 https://reprap.org/forum/read.php?262,633175,640889#msg-640889 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640889#msg-640889 BTW this is what E3D says

The E3D-v6 as sold is limited in temperature by the thermistor to 295*C but can go higher (tested up to 420*C)]]> amigob Printing Thu, 17 Mar 2016 12:48:52 -0400 https://reprap.org/forum/read.php?262,633175,640782#msg-640782 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640782#msg-640782

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amigob
I have a E3D V6 and by accident I was printing at 275c ( now 245c, and first layer 255c) . I didn't look at the PTFE tubing yet but it is still printing very well.
I am building a smaller lighter wade's like extruder so this weekend I will see how the PTFE looks like.

In my experience that melts the PTFE liner. For me the liner closes off and I have to use a drill bit to open it back up. But you might have been lucky]]> DRTak Printing Thu, 17 Mar 2016 09:26:35 -0400 https://reprap.org/forum/read.php?262,633175,640671#msg-640671 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640671#msg-640671 I am building a smaller lighter wade's like extruder so this weekend I will see how the PTFE looks like.]]> amigob Printing Thu, 17 Mar 2016 05:21:10 -0400 https://reprap.org/forum/read.php?262,633175,640385#msg-640385 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640385#msg-640385

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JamesK

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I think you have to use a metal hotend for PETG.

I was printing it at 250C with a ptfe liner. I haven't tried it in an all metal hotend yet.

Well, the ptfe liner in my nozzle melts above 260 deg. So I just have a little bit left in the inner bore. But I have removed it from touching the nozzle. I only left it in there for PLA.

JamesK. I just saw a video of PETG and taulman Nylon alloy 910. It looks like they have the same properties and PETG is cheaper. I really wanted Nylon Bridge but its way too flexible according to the reviews. Only difference is Alloy 910 is hard to break.

Right now, my PETG is crackling. I think it has absorbed too much moisture. But not much you can do when its attached to your printer for prints.]]> DRTak Printing Wed, 16 Mar 2016 12:21:44 -0400 https://reprap.org/forum/read.php?262,633175,640283#msg-640283 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640283#msg-640283

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I think you have to use a metal hotend for PETG.

I was printing it at 250C with a ptfe liner. I haven't tried it in an all metal hotend yet.]]> JamesK Printing Wed, 16 Mar 2016 08:44:31 -0400 https://reprap.org/forum/read.php?262,633175,640278#msg-640278 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640278#msg-640278 JamesK Printing Wed, 16 Mar 2016 08:28:21 -0400 https://reprap.org/forum/read.php?262,633175,640262#msg-640262 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640262#msg-640262

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Tinchus
Hi All. I would like some help with petg, please correct me if Im wrong:

1.- Pla starts to soften at low temperatures, ABS is more resistant to this, but can it be posible that, despite petg fusion temperature is around 230-250 (way higher than PLA), it starts to soften also at low temperatures? even lower than ABS ????? Would this explain why is ssomehow difficult to use petg with all metal hotends?

2- I have read thatn low speeds should be used. What do you mean with low speed? I have read people printing at 100mm/s ??!!!!! but someone speaks of 15 mm/s

thanks in advance,

Martin

1. I think you have to use a metal hotend for PETG. It requires temps above 230deg unlike PLA. I print PLA at 190.
2. Low speed is 15 to 50mm/s. 100 is PLA speed way too fast. You can adjust up from there. I adjusted to 43mm/s after testing a bunch of prints. I was trying to speed up print times.]]> DRTak Printing Wed, 16 Mar 2016 08:01:57 -0400 https://reprap.org/forum/read.php?262,633175,640228#msg-640228 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640228#msg-640228 I expect that the object was around 80 to 90 degrees. So to my opinion it can't handle heat that well. But I will try to use the new narrow ( wades type ) extruder with the e3D v6 so we will know. I don't know how warm the E3D becomes at the mounting point ( still need to buy a temperature meter gun )

2 my first layer is now printed at 20mm/s ( I call that slow) . Inner perimeters and infill at 50mm/s and outer 30 mm/s. My acceleration is now 500mm/s^2
I think at this moment the low acceleration is making printing PETG possible for me. I also use 20% overlap, The first layer still has problems attaching to the heatbed ( blue tape ). Removing it was not that big problem the extruder came of with the tape. When it was cooled down I already saw that the tape was pulled of the glass plate because I saw air bubbles underneath the tape.

[attachment 74674 WP_20160316_002.jpg]

it looks reasonably good , it feels very strong. I didn't fit the bearings yet, but I think the fit very tight. I had to drill the filament hole a little bit.

When I print the rest of the parts I will use no tape and the first layer method that DRTak mentioned]]> amigob Printing Wed, 16 Mar 2016 06:57:36 -0400 https://reprap.org/forum/read.php?262,633175,640213#msg-640213 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640213#msg-640213
1.- Pla starts to soften at low temperatures, ABS is more resistant to this, but can it be posible that, despite petg fusion temperature is around 230-250 (way higher than PLA), it starts to soften also at low temperatures? even lower than ABS ????? Would this explain why is ssomehow difficult to use petg with all metal hotends?

2- I have read thatn low speeds should be used. What do you mean with low speed? I have read people printing at 100mm/s ??!!!!! but someone speaks of 15 mm/s

thanks in advance,

Martin]]> Tinchus Printing Wed, 16 Mar 2016 06:32:20 -0400 https://reprap.org/forum/read.php?262,633175,640067#msg-640067 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640067#msg-640067 amigob Printing Tue, 15 Mar 2016 16:37:14 -0400 https://reprap.org/forum/read.php?262,633175,640057#msg-640057 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,640057#msg-640057
My hotened temp is 235 to 238. Fan is the enemy of PETG. At least for me. The only time I use a fan is for bridging. Otherwise I lower the temp of the nozzle and use NO fan. If I do use the fan you have to increase the nozzle temp a bit. My bed temp is now 73deg C.

I said this in another post. The most important thing for any print is the nozzle height esp for PETG. What I did to compensate for the z height is add a full thickness 1st layer. ie 0.4mm thickness for my .4mm nozzle. After that the PETG will stick to itself really well. But you cant have the fan blowing on it or the adhesion is terrible because it will cool to fast. If you want impossible adhesion make the nozzle -.05 to -.1. This will adhere to the bed so well that it will tear glass off of it. I only do this when I make a large part so that there is no chance of warping. This is especially true of a 6hr long print. I dont want any warping to happen 4hrs into the print and ruin the project.

Just my notes. I am no expert but I love PETG.]]> DRTak Printing Tue, 15 Mar 2016 15:54:21 -0400 https://reprap.org/forum/read.php?262,633175,639934#msg-639934 Re: At my wits end with PETG https://reprap.org/forum/read.php?262,633175,639934#msg-639934
[attachment 74623 WP_20160315_003.jpg]

I stopped the print because my stl was not complete support for the baring gap was not in the STL
But when stopping it I saw that I was printing at 275 degrees, oeps. I made a type in the slicer 345 iso 245.
It didn't do bad :-) no pollution on the nozzle.

So I will increase first layer temperature to 255, because I had still problems with the first layer I even reduced the acceleration to 500mm//s^2 and overlap to 25%. PETG needs some thing to stick to when doing small infills.
But with a bed temperature of 90 degrees the object says flexible.
I did some design changes and I will go to 7 perimeters so that I don't have the 1.5mm zigzag move.
I also think that I am going to do 100% infill, it seems to go way better then 60 or 70% in fill.]]> amigob Printing Tue, 15 Mar 2016 11:06:05 -0400