Tips to Get Your 3D Printer Up and Running

3D Printing

As seen in the July 2024 issue of Model Aviation.

IN MY PREVIOUS COLUMN, I mentioned that I would provide some helpful tips for getting your 3D printer up and running. Here are the first steps that I take when I get a new one.

Bed Leveling

Older printers had manual knobs to physically move the print bed, but all modern 3D printers have an automatic bed-leveling feature built into their firmware. With automatic leveling, the bed does not actually move. It is fixed to the printer, but a sensor measures all of the variations and dips in the bed, and then it uses that information to compensate when printing the first layer. If one corner happens to be a little lower than the rest of the bed, the printer knows this and lowers the print head in that area to compensate.

My Sovol SV06 and SV06 Plus printers preheat the beds to 40°C and the nozzles to 120°C before they level. This allows for thermal expansion of the parts. If your printer does not preheat, I suggest doing so manually. When it reaches the temperature, the automatic leveling process begins, and it only takes a few minutes for the printer to move from point to point to measure the bed.

Once this is completed, that data needs to be stored in the printer’s memory. The touchscreen usually has a menu function for saving this information. If it is not saved, it will not compensate, and that can lead to issues with the first layer printing incorrectly.

Z Offset

This is the gap between the end of the nozzle and the build plate. The nozzle needs to be close to the build plate but not too close and not too far. To adjust this, slide a sheet of paper between the nozzle and the build plate, and then change the value of the Z offset until the paper just starts to drag on the nozzle when you move the paper back and forth.

To set the Z offset, slide a sheet of notebook paper between the nozzle and build plate until the paper just drags when moved.

To set the Z offset, slide a sheet of notebook paper between the nozzle and build plate until the paper just drags when moved.

On the SV06, there is a wheel knob for changing the Z offset value. Care must be taken with this step because it is possible to jam the nozzle into the build plate if you change values too quickly. It is best to adjust slowly. I use regular notebook paper. Because paper comes in different thicknesses, be aware of the kind of paper that you are using. A heavier paper will set the nozzle on the higher side and vice versa.

Once you have the Z offset value set, you are ready for your first test print. Printers will typically come with a test file on an SD card to print. Once the filament is loaded into the printer, the test-print file can run. Common test files might be an owl, lighthouse, or a boat called Benchy. These usually take a couple of hours to print and give you a good idea as to whether your printer is set up correctly.

E-Steps

This test is to check whether the extruder is feeding the correct amount of filament. When you are 3D-printing an airplane, having correctly calibrated E-steps is important because it has a direct effect on print quality, wall thickness, and the weight of the parts.

The E-steps value should be checked and adjusted, if needed, to ensure quality prints.

The E-steps value should be checked and adjusted, if needed, to ensure quality prints.

The test is easy to perform once the hot end has been preheated. Take a ruler and mark a line on the filament 95mm, 100mm, and 105mm from the top of the extruder then command the extruder to feed 100mm of filament. On the SV06, this can be done using the menu on the display. Once the filament stops feeding, determine how much was consumed by measuring the marks left on the filament. The goal is for 100mm of filament to be consumed when 100mm is commanded. Typically, when 100mm is commanded, a smaller or larger value is actually consumed. This is because the factories set a "default" value.

If less than 100mm was consumed, it is under-extruding; a value of more than 100mm means it is over extruding. To correct this, the E-steps value stored in the printer needs to be adjusted.

For example, if your default E-steps value is 400 and you measure 93mm length instead of 100mm, the new E-steps value needed is 430.1 (400 × 100 ÷ 93). If you measure 105mm, the new E-steps value will be 380.9 (400 × 100 ÷ 105). When a new value is calculated and stored, the test is repeated and, if necessary, adjusted again until 100mm is consumed when 100mm is commanded. This step is rather critical to get consistent printing results.

If this process is not done, you will have to compensate for the difference in your slicer software, which can become frustrating, so it’s best to do this step at the beginning. You should not have to make any adjustments again.

Extruder Spring Tension Knob

One other item I want to talk about is the spring tension knob on the extruder. The extruder will have a spring-loaded lever that puts tension on the filament so that the gears inside the extruder can grab and feed the filament. Too little tension and the filament can slip; too much tension and it can cause binding issues in the gears.

A paint mark on the spring tension knob is useful for getting repeatable tension settings.

A paint mark on the spring tension knob is useful for getting repeatable tension settings.

Measure the amount of filament consumed during the E-steps calibration. When properly calibrated, exactly 100mm of filament will be consumed when commanded.

The best method I have found to adjust the tension is to feed some filament through the extruder, and then, while it is feeding, lightly grab the filament above the extruder with my fingers and see whether the filament slips or keeps pulling. I adjust the knob so that it has enough pull to keep feeding when I squeeze it. I then use a paint marker and place a dot on the knob. If I need to adjust it, I then have a starting reference point.

The springs that are used are fairly stiff, so a small adjustment makes a big difference in the tension. When I print rubber, I find that the tension knob needs to be reduced by one half turn because the rubber is soft. Having that mark means that I can then go right back to the previous position when I switch back to printing plastic.