Require a lot more heat for the same print...need some help

Last night I printed an object and it printed fine. Today I started printing the object and it started out fine but by half way my filament was starting to sputter (not sure what the official name is). I stopped the print and restarted it. From the get go I could tell something was wrong. So after a few hours of messing with it I found that the print that I did last night I ran at 200 Celsius and today I have to run the extruder at 230ish to get a nice smooth print without it becoming splotchy. With that being said it's still not printing as nicely as it did last night.

I'm printing in pla and no variables have changed fro the 2 prints. I used the same gcode on both and same filament. It was raining earlier today not sure if that makes any difference at all.

I thought I finally figured this thing out and was printing nicely now I can't seem to print anything.

Thanks

Sounds like there may be some plastic jammed up above the melt zone of your hot end, and the higher-than-normal heat is necessary to push past it. I'd turn up the heat really high--like as high as your hot end can handle--and run a couple cm of filament through it to hopefully get all the gummed up PLA burned out.

Also check the teeth of your hobbed bolt. It's possible that those have become jammed up with dry filment and aren't engaging with the feedstock as well as they were before, thereby decreasing their pushing power. After that, also try increasing the tension on your extruder idler.

I don't recommend putting up the heat as high as possible. A lot of nasty stuff can happen, this is the worst comment! How can you say that.

Plastics behave differently under higher temperatures, for example the polymers in ABS behave differently and the fumes may become more toxic than they usually are. Also, the setting process of the plastic may differ, you have a chance of the blockage becoming sort of permanently blocked because the plastic may get so hot it sets like a piece of concrete.

What I do then I have a blockage somewhere is pull out the filament, clip off the last part of the filament and then I put it back to see if the problem is gone.

As Pointedstick says, you can also inspect the teeth on the bolt to see if they are clogged, and also check if your thermistor is still looking ok. It might be thermistor failure?

Ohmarinus Wrote:
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> I don't recommend putting up the heat as high as
> possible. A lot of nasty stuff can happen, this is
> the worst comment! How can you say that.

It probably depends on the quality of your hot end. If you have some janky thrown-together thing that melts at 230º, then yeah, you want to be more careful. With most hot ends though, the firmware is going to stop you from going to a high enough temperature to do damage to it as long as there's some filament inside. Also, the poster was talking about PLA, which thankfully does not become toxic or harden at high temperatures. With ABS, you would probably want to have fan venting the fumes outdoors. But this type of blockage is less likely with ABS in the first place.

PLA actually hardens more than ABS when it is overheated and, even PLA has toxic qualities when overheated. It has to do with the polymers changing into a few other elements.

Just like burning human hair, it's just waiting to get cancer when you inhale burnt hair-fumes several times a day

Anyway, just a note of caution, there are some variables that are easily overlooked when experimenting with high temperatures.