MakerGear Forum

I've been using PLA and my prints were BEAUTIFUL...I mean TOP QUALITY for the first few months. Now, I am seeing banding a lot and the quality is POOR. I went back and re-configured it with the little strip and the screws...but it has not changed. I am desperate to get it back to how it used to be!

https://drive.google.com/open?id=0BzAp- ... pyV3hHQ3lj
This shows how things sort of "twist"

https://drive.google.com/open?id=0BzAp- ... hOUV9vV2pF
This shows a good one (old) and a bad one (new)

[urlhttps://drive.google.com/open?id=0BzAp-eYBywZFd3lzSDhMb3FFZ3hoWEViYXBZN1NVRnlwT3ow][/url]
https://drive.google.com/open?id=0BzAp- ... l0anFuYlpV
This shows how detailed and fine it used to print

https://drive.google.com/open?id=0BzAp- ... 4wLU1tY2M4
This is newly printed and you can see all the lines and banding

All other things being equal (like you haven't changed the temperature or anything) - is your PLA getting old?

Humidity has a very negative effect on PLA if it isn't stored in an arid environment (with a desiccant) when it's not in use. It absorbs the humidity over time, and starts to get brittle, affecting the feed rate and the prints.

Another possibility is that you have a bit of charred debris in the nozzle that is partially blocking the flow. (One of those looks a little wavery to me.)

No, the PLA is brand new Hatchbox filament.
But yes I have been noticing wavy lines when the prints start for a bit.

All other setting have been the same.

What would I do about debris in the nozzle?

and thank you for your reply.

Easiest thing by far is to keep a couple of replacement nozzles on hand (they're only ten bucks each) and (remove the whole hot-end first by following the video) change out the nozzle.

Nozzles are considered consumables. You will likely run through one or two a year if you don't use a filament dust filter on the filament before it feeds into the machine. There is just a lot of junk on the spools from manufacture, and even if you run one, you can get a little bit of fluff that gets in there and chars. The opening of the nozzle is so small that anything can block it.

Once you have removed the clogged nozzle, you can use a blowtorch to clean it, or soak it for several hours in solvent depending on what kind of plastic you have been using.

Only thing is....if you replace the nozzle, you need to re-set the Starting Height.

You can also use a short section of E-string (guitar) to CAREFULLY poke up into the bottom of the nozzle to dislodge the blockage, while the nozzle is hot. Not the easiest thing to do, but it will dislodge junk sometimes and get it flowing again. You do have to be careful to not damage the opening if you try the wire.

Or it might just be a bad spool of filament. Sometimes you get a bad batch. Try a different spool before you go in to clean the nozzle.

I guess it looks like I have to get some nozzles then, I really dread trying to replace anything on this machine.
Thank you so much for your help Jules its greatly appreciated

No problem! And replacing the nozzles is super simple....just follow the videos here to remove the Hot End and then the nozzle:

Remove the Hot End: https://www.youtube.com/watch?v=OdducxLlZyk

Remove the Nozzle: https://www.youtube.com/watch?v=tyoxU0RbVS0

great to hear! thanks again Jules!
We are going to go for it

btw what type of solvent do you recommend I try to clean the old nozzle with?

The solvent for PLA is pretty harsh. Any paint stripper with methylene chloride in it, and it takes an overnight soak sometimes.

Try to do a cold clean first.....instructions here:

viewtopic.php?f=3&t=2942

wisdomknight wrote:great to hear! thanks again Jules!
We are going to go for it

btw what type of solvent do you recommend I try to clean the old nozzle with?

Fire.

Remove the nozzle, hold it gently with pliers, hit it dead-center front and back with the blue cone of a propane torch's flame. Do not use an oxygen-boosted torch. Bring it to a dull-red color and drop it straight into a small paint can of denatured alcohol. If you lower it slowly, it'll catch fire ... if you drop it into the can it'll both NOT catch fire, and ablate the remaining ash with flash-boiling.

If you have any further questions about safety, you probably shouldn't do it.

ROFL! Killing off the customers...never a good idea!