SOLVED Nylon problems - see pictures

[SOTS 0]

Hey,

We've had problems printing with nylon:

Does anyone know what's going on here and how to fix it?

Print setup and material settings:

[Labern 774]

Have ypu tried printing a simple test object with Nylon?

Did you hear crackling and poping sounds as it was printing?

What were the results like using the default profile?

In my experience the moisture content in the nylon plays a big part on how well it prints and making sure it's nice a dry can eliminate more issues I'm seeing in your print.

[SOTS 0]

Thanks for the reply:)

We've printed various objects with the same results as shown.

Minimal crackling and popping sounds. We adressed this anyway by drying the filament in an drying oven for several hours at 75 degrees celsius.

The first print, started minutes after unpacking the filament and with the default nylon profile, came out good:

The second print and the prints after however failed. Therefore the tweaks in print setup and material settings.

Things we've tried:

 

• Loosened the grip on the filament to reduce grinding
  
• Atomic method and cleaned the nozzle with a needle - thickness of layers seemed smaller than it should've been and we thought some blockade may have caused under-extruding
  
• Printed with other materials in between to make sure nothing was wrong with the printer
  
• Recalibrated the build plate
  

 

Any ideas and tips is appreciated

[kmanstudios 1,120]

Sounds more like a humidity issue if it starts out fine and then gets progressively worse. Tweaking settings can only compensate for so much as humidity can collect and get more problematic as time goes by.

[SOTS 0]

We hoped 4-5 hours in a drying oven at 75 degrees celsius would be enough. We'll dry it for a longer period and then try again with the default print settings.

[kmanstudios 1,120]

We hoped 4-5 hours in a drying oven at 75 degrees celsius would be enough. We'll dry it for a longer period and then try again with the default print settings.

When you took it out, did it perform as expected and then get worse or just stay bad in response to printing needs.

If it started out ok, then it points towards the filament just starting out dry and then getting moisturized again.

And, humidity can be a factor in the machine as well as it can affect the bowden tube friction as well as other connection issues such as feeder slipping or starting to grind on softened filament creating a buildup in the knurling pattern.

Edited August 23, 2017 by Guest

[Labern 774]

Minimal crackling and popping sounds. We adressed this anyway by drying the filament in an drying oven for several hours at 75 degrees celsius.

The first print, started minutes after unpacking the filament and with the default nylon profile, came out good:

So is this what the print in your first post is meant to look like?

Did you put the tension of the feeder back after drying it?

And did you also revert all the CURA changes back to default after drying?

[SOTS 0]

When you took it out, did it perform as expected and then get worse or just stay bad in response to printing needs.

If it started out ok, then it points towards the filament just starting out dry and then getting moisturized again.

And, humidity can be a factor in the machine as well as it can affect the bowden tube friction as well as other connection issues such as feeder slipping or starting to grind on softened filament creating a buildup in the knurling pattern.

It performed as expected the first few millimeters. Then it seemed like it stopped extruding as much material as needed and ended up as in the first picture. The first few millimiters is actually quite strong when I bend and stretch.

If the part is still too moist I guess a longer drying period is the only solution?

After drying we immediatly put the print on, could the filament be too hot for the feeder? That doesn't explain the successfull first few millimeters though.

[SOTS 0]

So is this what the print in your first post is meant to look like?

Did you put the tension of the feeder back after drying it?

And did you also revert all the CURA changes back to default after drying?

This is the first print we did immediately after removing the vacuum package - which is how we want the print to look like.

We're pretty sure there was enough tension. Quite a lot of force was needed to put it in the feeder.

We didn't use the default settings on this failed print. We'll dry it overnight and try again tomorrow morning with the default settings.

[SOTS 0]

Let the filament dry for 18-19h at 70 degrees celsius in the dry oven and tried to print again this morning. It did wonders . 4-5h was too short it seems.

We used a raft (default settings) but it slid of the raft mid-print. Solved this by just using a brim on the next prints.

Checked the humidity in the room and it was 59%. Too high may cause problems? Perhaps it will be easier to print during winter.

We've got our question answered. Thanks for the help!

Edited August 24, 2017 by Guest

[Labern 774]

That's great. Just make sure you keep the filament in a sealed container with some desicant to keep it dry.

[tomnagel 126]

I've been told by our material experts that once you let your Nylon absorb moisture, you won't get it all out with drying in an oven. The water bonds chemically, and changes the properties of your Nylon.

So keep it dry.

In a humid environment, this may mean you have to improvise something to keep it dry. On the forum you can find examples for this (plastic boxes etc)

[geert_2 557]

I store all filaments in huge sealed boxes with a big (!) bag of disseccant, so they are dried and then stay dry. I use the sort of disseccant that is sold in car shops to dry car interiors and prevent condensation on the windows. They have a blue indicator that turns pink when the bag needs to be reheated in a microwave or other oven.

For nylon, you should also put the spool in a sealed box with disseccant *while printing*: otherwise it may absorb too much moisture in only a few hours. This may require some bricolage: you need to make a spool holder, a small exit hole, and a holder for the disseccant in the sealed box. Polypropylene food storage boxes do exist in suitable sizes.