Support my habit, Get cool Stuff

Tuesday, June 26, 2012

Well... it is faster

I printed this piece so I could have something to compare the new print quality versus the old print quality and I was surprised that the new print quality went to crap. It prints faster, sure, but what it prints is not as good as it used to be. So I'm going to put some details here and see if I can get any help from the makerbot community. This was printed using out-of-the-box defaults for RepG37, 100mm/s feed and travel rate, 1.78mm filament diameter, etc.
  • The whole thing has a "bumpy" feel to it, where as the old one was smoother. Bumpy edges, bumpy flat sections. It doesn't really come through in the picture but it's really messing up my chess sets.
  • Another thing that's messing up my chess sets is that the tolerances are all off. maybe that's the bumpyness, maybe that's the new skieners. But where before I had snug fits now I have impossibly tight fits that need sanding, which is sometimes impossible.
  • The bumpyness seems consistent all the way up, making vertical ridges on what was before flat surfaces. These ridges seem to follow the geometry of the wall as it changes, tho I've had a hard time catching a picture of it.
  • The pyramids on the Acuracy Master Test seems like some of the layers aren't sticking, so there's a gap in the back which hopefully you can see in the picture. The smaller one just looks... blotchy. Same problem with the chess set, small details getting less connected.
  • The tips of my chess pieces always had this strange gap, a hole right into them. It's gotten worse.
  • My X-axis (running front-to-back) seems off. If it looks like there's 30mm clearance on top it'll be right at the edge on the actual print. This may have been a problem before that I just didn't notice. More investigation may be necessary, but any tips would be welcome.
To be sure it's not just an artifact of going 100mm/s I slowed the feed rate down to 60mm/s (kept the travel rate at 100mm/s) but the result was pretty much the same. Same ridges, same tolerances, same problems. I'd like to stick with the new upgrades, so I hope someone out there can help me.

EDIT: In trying to capture the side-by-side image below of the old print quality vs the new print quality I noticed that the old prints did indeed have bumps that resolved to vertical ridges that followed the geometry of the shape but they were more subtle, almost invisible. Now they stand out like a sore appendage. That coupled with layers not sticking to each other... I really could use some help.
New print on the left, old print on the right.


  1. Hi Joseph,

    There are several unrelated issues you mentioned. I'll tell you what I know about each:

    Offset: This has to do with Dual/Single extruder all of the times I've seen it. Male sure you set that correctly on the LCD screen. I also recommend doing the dual-extruder calibration if it applies, also from the LCD.

    Waviness: There are several factors that can cause this. You should be able to stay at or below 60mm/s and not see it any more than before as long as you're printing from an SD card. Over USB you probably need to stay below 40, maybe even 30. You can do the infill and travel much faster, but keep in mind that below 240°C, the extruder won't be able to keep up, and even at that with >.2mm layer heights you should stay below 80mm/s if you can't have some gaps in the extrusion.

    Layers sticking: That's both temperature and environment. Basically, keep it from air flow. Possibly raise your extruder temperature some.

    1. Really surprised that you recommended I raise my temperature. In the past I had to raise it a bit but with the new version being higher than I even had it before I figured I'd be good. Isn't 240 enough? Alright, I'll try higher (wow).

      So if the settings on my LCD say that I an in dual mode, and the calibration looks good, what do I blame on my homing being off. This is a 3 cm difference here and it's on the X axis, not the Y like you'd expect... Oops, I said "Y" in the post. Gonna ninja edit that.

  2. Sorry, 240° is high enough. I assumed that, like many, you edited it back to 220°.

    It's not what the LCD says, it's the process of setting it that re-initializes the EEPROM for the offset between the nozzles.

    1. Ah, good to know. I'll do that. However, like I said, the problem is in the X-axis and I just watched my printer, when it was setting up to print, move the X-axis to it's furthest extent forward, hit it, then jump backwards about 30mm. What is causing this behavior and how do I fix it?


Note: Only a member of this blog may post a comment.