Ooooooooozzzzzee

[dennisjm]

I have a role of PET+ I've been experimenting off and on with. Seems to work pretty well except one bit. The ooze is out of control. If I let it sit there with the nozzle hot you can see it oozing out at a pretty fast rate. I think the whole role would ooze out if I wasn't printing.

Ok, so I've played with retraction and coasting and what not and I can do prints OK for most types of prints. Specifically troubling though is when I do a sparse infill. Like 10% or 20% infill and the problem is that plastic builds up on the nozzle. I have to pause the print and clean off the nozzle regularly or it'll ruin the print. Annoying for a large print of course.

So question is... anyone have luck with the "experimental" ooze rate setting? What do you set it to... the rate that plastic is coming out while the extruder is just sitting there?

[Joey]

I personally haven't printed with PET, but the higher the temperature the more viscous the material will be. What temperature are you printing at? Have you experimented with dropping the temperature a bit?

[dennisjm]

I've tried everything from 240 to 260. I believe I may have tried lower but couldn't get the prints to stick or had poor layer adhesion.

[Joey]

I've tried everything from 240 to 260. I believe I may have tried lower but couldn't get the prints to stick or had poor layer adhesion.

What kind of printer do you have, and what are your current retraction settings?

Retraction Distance=?
Extra Restart Distance=?

[dennisjm]

Flashforge creator X

I'm using retraction = 1.5mm and coast = .5 but I haven't experimented with extra restart distance and wipe. Maybe those will help too. I was wondering what exactly the ooze setting in advanced does though... this seems like it would be applicable.

[jimc]

Im not on a flash forge but i have printed a ton of pet+. When i get back to my computer i will check my settings and give you some real numbers but i can tell you right now your retraction and coast are nowhere even close. Have you printed with nylon? The pet oozes just slightly less. My retraction is around 3.5 and voats around 2 if i remember correctly. I do use the ooze control a little but ill get back to you on those #'s.

[jimc]

ok here you go. now this is for my makergear so wont really apply to you but will give you an idea. temp i run at 245. retraction is 3.2, restart is (neg) -.05, ret speed 3000, coast 2.00mm. the exp ooze setting on the last tab i have off for the clear and 20mm/min for the black/opaque colors. i know that ooze rate setting you want to keep low. i did some testing with it awhile back to see what it does and it somehow lowers the extrusion amount so if you have it set too high it will under extrude so you will find yourself wanting to jack up the multiplier. just keep it at 20 or lower. the hot end plays a big part in the ooze rate. i just got an e3d which has a very short thermal zone compared to my makergear v3b so i was actually able to cut the retraction and coast amounts in half. i love the pet+ and its my first choice to print with over any other plastic type. you just have to get your machine tuned for it. for me, i started with nylon and got used to that first so switching to pet+ was no big deal. people that go from pla to pet usually freak out a bit and cant control the oozing because they are not used to having settings that high.

[Joey]

ok here you go. now this is for my makergear so wont really apply to you but will give you an idea. temp i run at 245. retraction is 3.2, restart is (neg) -.05, ret speed 3000, coast 2.00mm. the exp ooze setting on the last tab i have off for the clear and 20mm/min for the black/opaque colors. i know that ooze rate setting you want to keep low. i did some testing with it awhile back to see what it does and it somehow lowers the extrusion amount so if you have it set too high it will under extrude so you will find yourself wanting to jack up the multiplier. just keep it at 20 or lower. the hot end plays a big part in the ooze rate. i just got an e3d which has a very short thermal zone compared to my makergear v3b so i was actually able to cut the retraction and coast amounts in half. i love the pet+ and its my first choice to print with over any other plastic type. you just have to get your machine tuned for it. for me, i started with nylon and got used to that first so switching to pet+ was no big deal. people that go from pla to pet usually freak out a bit and cant control the oozing because they are not used to having settings that high.

I think adopting some of Jimc's settings will help, that a negative restart distance will help your retraction settings and help remedy the ooze problem you're having.

[AndersE]

I don't know what pet+ is, but i have printed a lot of nylon lately, and i have 7-8mm retraction and 2-3mm coasting. That gives me the least oozing and stringing at 260c.

Should perhaps play a little with the ooze control also..

[dennisjm]

just keep it at 20 or lower.

Wouldn't it make sense to set it at whatever the material actually oozes out at. In the case of my PET+ when the extruder is hot it oozes out fast enough that I could measure it and get an exact number. I'd bet it's under 20. Haven't tested yet though.

Thanks all for the input on retraction. I'm eager to test these out next time I get the PET+ out to see if I can get better results. With it where I have it now I can get pretty good results on solid models. It's always when I start to cross sparsely filled areas that the material starts to pick up on the nozzle and cause issues.