Print quality is now dreadful.

[fingerpuk 0]

Hello all.

Initially I was able to get really good prints, I ran at 0.06 20mm sec at 210, 60 degree build plate and the surface quality was really nice.

Now though, same filament and same settings, on the same GCode, I get nothing usable out of the machine. I get under extrusion, over extrusion, blobby surfaces, and lots of stringing.

I've tried re-threading filament so it's got a clean path (building a nice spool holder now with bearings to support the spool), I heat up the build plate and the nozzle and move filament so the nozzle is clear and charged. The new firmware and Cura export some filament initially and this is working. It's just when I get part way into the print the under extrusion seems to occur. The stringing and surface blobs are everywhere from the start.

Any thoughts?

Cheers.

 

[illuminarti 18]

It would be helpful to see some photos to understand what your prints are doing. What type and brand of filament are you using?

 

[braddock 1]

Can you post a few photos? maybe do a nozzle clean removing the material, unscrew the 4 main bolts, heat heat to 200, and manually insert a piece of material directly into the hot end, mush it down, then cool to around 100 degrees and pull it out, it'll remove any gunk with it.

Also, before I kick off a print, I always manually move material until I get a nice flow. If it's restricted, grab the material with your fingers below the feeder and apply a bit of force pushing it through while turning the click wheel to move material... this helps get things flowing again if there's a slight blockage.

 

 

[valcrow 144]

I would Re-measure your filament in a few places with a caliper and plug that number into Cura and don't try to fudge it. make sure flow is at 100%.

I fudged it once to get more extrusion on the top layers to fill in more... eventually I forgot about the change and on larger prints, it would under extrude dramatically seemingly randomly. When it slowly builds up too much pressure and starts grinding the filament it'll just stop extruding properly. I didn't figure it out for days.

 

[fingerpuk 0]

Hello.

I'll post some images later, I threw away the failed print so am re-printing now. The brim goes down perfectly, but the finer layers don't seem to touch, it looks like under extrusion but the material flow is free and easy.

I'm using the filament that came with the printer, I may switch it out later to some grey filament given to me by the iMakr store in London. I don't know the brand as it isn't labelled. I may buy some more if anyone can recommend some?

If this print fails I'll attempt a nozzle clean. I manually put some material through the nozzle at the start of each print, and like I say the brim and rafts are very nice. So it's the thinner layers that it fails on, 0.1 and below. I print at .06 normally. I'm printing now at 210 but I normally print at 200 for .06 layers at 30mm a sec. Wanted to see if higher temps will help the flow.

I measured the filament, it varies from 2.83 to 3.01mm in diameter. It's all over the place, I'll test the other roll.

Cheers.

 

[illuminarti 18]

Higher temps will definitely help. But having filament vary above 3mm in size isn't a good sign at all.

Since you're in the UK already, http://www.faberdashery.co.uk filament would be an obvious choice. It's not cheap, but to my mind, it's the best there is.

 

[yellowshark 153]

+1 on Faberdashery but stay away from the Galaxy Blue. It is "flecked with sparkle" and looks real nice but the sparkle is bits of other filament and I found it quite easy to get a blockage. Get some experience then try it .

Also with Fab you do not need to buy 100mtr reels; you can buy a colour by the metre eg. 30mtrs of white, 20 mtrs of a blue, for trying out different colours it is really useful. Buying 100 mtr reels is the cheapest option though

 

[illuminarti 18]

YMMV. I think Galaxy Blue is awesome - I've printed a lot with it, and never had a blockage at all.

[yellowshark 153]

Lol which only goes to show that filament can be the mother of all evils. It has stayed on the shelf ever since so maybe when I get a slack schedule I will give it another try.

 

[ian 32]

as the lads mentioned.. a photo sayy everything.. let us see whats going on and we better pin point the problem.

Ian :-)

 

[gr5 2,173]

If it hits 3.01mm it's probably getting stuck in the bowden. :(

Throw it away. Sorry to say this but that's by far the best solution.

Alternatively, take some sheet metal and drill a 3mm hole in it, then pass filament through it and chop up the filament and discard bits that are over 3.00mm. Then give up and throw the whole thing away anyway. :(

 

[woofy 12]

YMMV.

 

Haha, I had to look that one up.

[Guest]

Hi! I believe my filament get squeezed through the extruder too tight. (The screw at the extruder is at the top, showing the least amount of tightness.)

So when my filament gets squeezed too much the diameter of the filament expands. Could this be the reason to some of my prints get bad quality layers because going through the teflon tube it's more resistance?

 

[gr5 2,173]

So when my filament gets squeezed too much the diameter of the filament expands.

 

Very reasonable theory. For 2.85mm standard hard PLA it's usually fine. Some people have taken apart their feeder and either cut a loop off their spring or filed down the white swing arm a little to reduce the tension. I've been fine so far - I haven't even taken my feeder apart yet. Although I'd like to print IRobertI's design some day. It allows for easier filament change.