Tag: 3dprint

Sometimes prints will have issues only at a specific height. The symptoms may be poor fill at a specific height, layer shift that always occurs at a certain Z, or something else that seems to consistently occur at a certain height.

When this happens, I start looking at, and around, the lead screws for Z. I look at the motors, the screws themselves, and the bearings. When I inspect the lead screws, I make sure there are no physical issues, such as nicks or dings in the screw itself and that the lead screw isn’t bent in that location.

I had a mishap over the weekend that made me have to stop my print. The print was too long and I had too much into it to want to start over, so I decided to print the other piece and glue them together.

As I was doing it, I noticed how well the pieces fit together. I’ve done this in the past and the parts didn’t fit together well. I’ve spent a lot of time tuning my printer and making sure that it is printing to the proper sizes.

I realized that one of the benefits of this effort is that, when things do go wrong, I am able to put the pieces together because the sizes match.

I’ve seen a number of people asking for functionality related to controlling or monitoring their printer remotely. The easiest way is to set up a Raspberry Pi and attach it to your printer. With the price of Raspberry Pi’s right now, though, this is a significant cost. I’ve had good luck with Armbian on a Le Potato that costs substantially less. After some experimentation, I ended up replacing the firmware on my printer with Klipper and putting Klipper on my Le Potato. It’s been working great.

If the sides of a calibration cube are a little bowed, there are a couple of things that I would look at.

  • e-steps/rotation distance (Klipper): if your extruder is extruding too much material, the material has to go somewhere.
  • calibrate Z: same thing as above, if your z steps are off, you might not be moving up as much as you think you are. The extruder is calibrated to extrude a certain amount of material. If you end up extruding more material, it needs to go somewhere
  • pressure advance: your nozzle may be oozing a little bit and causing your sides to become bowed

The quick answer: Yes

When you first start out 3d printing, you most likely will not know whether that stringing issue is caused by poor retraction settings, temperature settings, or something else. I don’t do it anymore, but when I first started 3d printing I kept very detailed logs that included every parameter setting, as well as the ambient temperature, the type of filament used, and a description of the overall 3d print outcome.

I found these records to be very valuable in troubleshooting. They provide a lot of insight into what might be wrong when I change filament or what has gone out of whack if I don’t change anything on my printer but it just starts acting up.

After a while, two things will happen.

  1. Your machine will get more dialed in. This is just a natural result of tinkering with the settings and getting incremental improvements out of it over time. Once your machine is dialed in, any parameter changes will be pretty minor.
  2. Your knowledge will grow. You will start to intuitively know what setting needs to change based on how your printed part looks.

It’s not necessary to keep detailed logs indefinitely. When you are starting off though, I can’t think of any better way to build your knowledge base.

I notice that new users often post something similar to “I just got my first printer, what should I upgrade first?”

My answer is usually “nothing…for now.”

Don’t get me wrong, I’m not opposed to upgrades. But this post is more specific to new users. There is a lot to learn when you first start out 3d printing. Proper temperatures, speeds, loading your print correctly. There are slicers, different cad packages, and the list goes on. Don’t add more complexity to the situation by upgrading a bunch of items on your printer. Learn your printer. Once you feel like you have a good handle on the stock printing process, maybe try out a small upgrade and just work your way up from there.

I saw a user in a forum asking for help with bridging. They were trying to create a large print that had many bridging features that were intended to be straight across and ended up being droopy.

When someone asked what they had done already, they responded with “I slowed down my speed to help the bridging out.” In most cases, this is the opposite of what needs to happen. If my print has a lot of bridging features I typically speed it up. If you think about the mechanics of what is happening here, heat is being applied the entire time that your nozzle is extruding. So, the longer something takes with heat being applied to it, the more it will sag as a result.

I’ve printed parts in the past that end up looking like something was dragged across the surface while it was printing. In reality, something may have been dragging across the surface. The first thing that I check when this happens is to make sure that the nozzle is clear. This is a typical sign that the nozzle may be clogged.

If it does turn out to be clogged, I do a “cold pull.” Heat the nozzle up 20 – 25 degrees past what you use it at during printing. Then let it cool completely. The idea is that any debris will collect into the filament. Once it is cool, heat it up again but tug on it from the extruder end. It will break loose from the nozzle at a much lower temp than what you print at. Hopefully, any debris that was clogging the nozzle comes with it. Just cut the end of the filament off and feed it back in.

Sometimes I print parts that have a top surface that look like a riverbed. There are valleys and branches going all across the surface of the part. This is usually a result of the nozzle being too close to the bed. Mechanically, there is too much filament coming out of the nozzle for the amount of space between the bed and the nozzle. When this happens the filament flows into other areas of the print and creates these valleys.

In short, your nozzle is too close to the bed if you have this. Adjust the height or redo your bed level.