1

Im printing PLA with a Wanhao Duplicator i3, and I have a problem with printing thin columns like the roof supports on this Benchy:

There seems to be a problem when the extrusion is really short, and the layers don’t stick together properly, making the print very brittle in these places.

The above print was done at 210C (60C bed). The higher than usual temperature is because of the Micro Swiss MK10 hotend, which seems to require this.

I’m using the standard software that came with the printer (Cura Wanhao Edition).

Here are the printer settings:

What could be the cause of this behavior?

2

Hi there,

Maddie here from 3D Hubs.

I just wanted to let you know that it looks like your image isn’t appearing correctly. I’d recommend uploading the image again.

Regarding your question, could you add what slicer you’re using? It might help others determine how to best help.

Good luck!

Best,

Maddie

3

What are your settings? Did you do a bed calibration with a thin piece of copy paper before starting the print?

4

Yes, I did a bed calibration.

5

Looks like it might be underextruding. Are you sure the problem is with thin support and not just amount of time into the print? It’s possible you’re getting heat creep, which causes the print material to start melting too far up in the hotend, which mucks with the flow rate. It usually won’t happen until partway through a print because, as the name suggests, it takes a little wile for the heat to creep up. It could be that you’re actually printing too hot, it could be that you don’t have good contact between your hotend and your cooling block - there are a number of problems that could cause it.

A few things you can try to help figure this out:

-Print an object that takes the same amount of time as the Benchy, but doesn’t have the thin supports and see if you get a similar problem.

-Print at a lower temperature. I find my i3 with the MicroSwiss hotend does best at 205C for most PLA.

-Point a small fan at the extruder while printing a Benchy. It might blow on the part a little, too, but PLA doesn’t tend to warp too much, thankfully, so it shouldn’t cause a problem. If you find that the fan fixes your issue, it’s almost definitely heat creep.

Oh, for reference, is which generation of the Wanhao Duplicator i3 is this?

Good luck! I hope at least some of that is helpful.

6

Thanks, I’ll try that.

I’m not sure which generation it is exactly, here’s a pic: http://i.imgur.com/QRsmIDt.jpg

7

That’s the V2 (second generation). You might also want to make sure that the rails your extruder travels along aren’t loose. Mine came loose and I ruined a few prints before I realized what had happened.

8

Yeah, mine had a rail loose too when it was delivered, but I fixed that right away.

I lowered the temperature, and the columns print ok now. I did try to print stuff at higher temperatures for longer times (5h+), and it seems that it is only the combination of the high temp and thin elements which produces the problem.

Anyway, problem solved, thanks for the tip. I was tinkering with all other setting EXCEPT the temperature, and it would have taken me months to figure it out probably :slight_smile:

9

Glad you got it working! Thanks for replying with the solution, too.

Edit: BTW, if it’s only happening with the thin elements like that, it might also have something to do with your retraction settings - possibly a combination of too much retraction and a small amount of creep. If you find your prints aren’t as nice at the lower temps, you could reduce the retraction somewhat and increase your temps again to see if you can find a good middle ground.

10

You could try increasing your nozzel temprature by about 5 or 10 degrees