Getting Started with the Peopoly Moai SLA 3D Printer
MatterHackers' Pros detail the unboxes and set-up steps of the awesome Peopoly Moai SLA 3D printer.
There are many different kinds of 3D printers out there, with most of them based around heating up and extruding molten plastic. These are great for large, relatively low details prints, but what if you need a small, super detailed model like a ring: enter SLA 3D printers. Rather than use plastic, they use a photosensitive resin, which is a technical way of saying it uses a laser to solidify the resin.
The Peopoly Moai is an SLA 3D printer that got its start through Kickstarter, and unlike most, it delivered only three months after the Kickstarter successfully finished. At $1295 for a kit or $1995 for a fully assembled Moai, it’s one of the cheapest SLA printers out there. As a kit it’s really easy to put together, even for someone that’s never assembled a 3D Printer kit before. Being an SLA printer vs an FDM printer, there are some things about your workflow that will need to be different in order to print with it successfully. Let’s dive into what exactly is different and the experience of working with the Peopoly Moai SLA 3D Printer, from unboxing to first fully-cured print.
The Moai is packaged really well, with lots of foam, accessory and hardware boxes, and layered packaging. I went from box cut open to all parts fully laid out in five minutes flat. You’ll want to make sure to look through all the pieces and parts and make sure they are all there, as in my case I was missing the door latch. Peopoly was really great about this and got a replacement part out as soon as they could.
On the SD Card are the instructions for putting together the hardware, but they are also listed online here. The steps are really easy to follow, but there are a couple tips I have for assembly:
- Leave the screws holding the frame together just slightly loose, and only tighten them up right before you attach the panels onto the side.
- Remove the protective cover right before you install them, and pull the cover parallel with an edge. Trying to pull at an angle or perpendicular to the edge just caused the sheet to tear and come off in pieces.
- Do proper cable management. Keep them zip tied and cinched close to the panels or boards to prevent them from getting in the way of the laser.
- Leave the right panel off the side of the Moai until it’s completely calibrated. You’ll need to access the internals.
All in all, despite never assembling a 3D printer kit before, let alone a Moai, it took me only two and a half hours to assemble it.
You’ll need to do a couple tests and calibration settings before you attempt to print anything, so be sure not to pour in any resin or insert the vat until it tells you to.
Test 1: Power Check
- Plug in the power supply and click the power switch. It should light up blue if the printer is on. When it turns on, you should see two things happen:
- The Z Axis is raised to the top before stopping
- The plate will tilt the right side down and back up to level.
- Clicking the selector knob once selects the option highlighted in red, clicking it twice goes back one page.
Test 2: Settings
With the installed firmware, most of these settings should be correct, but there may be a couple that need tuning depending on the version your machine is shipped with. If you are not on firmware 1.16, please follow the instructions to install the new firmware here. Currently, the recommended settings are:
- X Size 900
- Y Size 900
- X Deviation 100
- Y Deviation 100
- Smooth 50
- Z moto speed 8
- PM moto speed 60
- Laser Power 58
- XY Speed Set 4
- Z Reset Position 1877
- PM Reset Position 40
- Z Follows 40
If you ever decide to use resins that aren’t from Peopoly, Laser Power is the setting you’ll need to play with within these settings in order to change how much exposure the resin gets. 58 is the power that has been found to work best with Moai resins.
Test 3: Galvo Test
While the galvos are aligned before shipping, it's possible that there is some margin of misalignment after it arrives. Peopoly has since addressed this and has a detailed guide on how to correct this here
Included on the SD card is a circle test pdf and gcode to see if the galvanometer is working properly. Print out the circle marking, making sure that it isn’t scaled-to-fit the page and that it is printing at 100% size. Then cut it out along the outer lines of the rectangle. Place the this piece of paper in the vat and insert the vat onto the platform. Make sure the aluminum build plate isn’t screwed into the top yet too. The side with the inner edge closer to it is the side that should be placed closest to the Z-axis rod. The gcode you should run is called “P _yuan-test.gcode” in the “gcode” folder. The test will run for a while, but all you need to see is that it traces along the larger circle and isn’t coming out as a weird shape.
Peopoly is constantly updating their build guides and calibration techniques to make the assembly process easier and more precise. The most recent change has completely eliminated an entire series of steps and simplified the process. The current way to level your Peopoly Moai is to:
Your bed is now leveled enough, but for a high precision level (and to prevent extreme elephant-footing of your prints) there's a secondary procedure to more accurately level the bed.
- Download the Leveling Test gcode file, load it onto your SD card, and insert it into the printer.
- Set the laser power to 58 (if it isn't already) and start the print.
This gcode will print a cylinder in each of the corners of the build plate, with the letter on top corresponding to the same corner within Cura Peopoly Edition. These cylinders are designed to be 11mm tall, but depending on your leveling they will be shorter than that in varying amounts.
- Once the print is finished, remove the four cylinders from the build plate and clean them with IPA
- Use a set of calipers to measure the height of each cylinder and note which cylinder you are measuring.
- If you are looking at the build plate from above, A is the front left corner near the door, B is the back left corner by the Z axis screw, C is the front right corner near the door latch, and D is the back right corner.
Depending on how much the build plate is pressing into the PDMS layer of the vat will affect how tall the cylinders are. The goal is to have each of them measure 10.7mm tall.
The pitch of the thread on the nuts is 0.7mm, which means a full turn will raise or lower that corner of the bed 0.7mm. Tightening the nut will increase the cylinder height, and loosening it will lower it. If, for example, your cylinder is measuring 10.35mm tall, then tighten that corner a half turn to bring it up to 10.7mm tall.
If there is a corner that failed, where the cylinder didn't print completely, loosen the nut in that corner a full turn and try again.
Download this test gcode for the Moai and put it in the “gcode” folder on the supplied SD card. Any gcode you have needs to be in the folder named “gcode” otherwise it won’t be able to find it. After it’s loaded, go ahead and insert it into the Moai and start the print. It should take about 20 minutes to complete, and will be printed in the back left corner, so don’t be surprised to not see it centered.
From here, a couple things can happen:
- Print completes without problems.
- Success! Congratulations, it’s fully assembled and ready to go
- Nothing is on the plate, but a flat piece is in the bottom of the vat in the back left corner.
- Make sure laser power is at 58, and xy speed is at 4. If it is, start another print and watch to see that the plate presses into the vat. You should be able to see the vat lower just the smallest amount. If it doesn’t loosen the leveling nuts ¼ turn and try again. If the settings are right and it presses into the vat but your prints are still failing, I was able to solve this by using the supplied spatula to scuff the build plate (not the vat). Not too roughly, but just enough to give a small amount of texture to the plate. This seemed to solve my problem.
- Half of the ring printed but part is broken off.
- Try increasing laser power by 1 at a time. This is a sign that the resin isn’t getting enough exposure from the laser and isn’t curing fully, creating a weak 3D print.
- The ring is printed, but there’s some odd artifacts like there’s a line cut through it.
- Check and make sure you don’t have any cables in the way of the laser. Zip tie and clamp them as close to the panels as you can, to keep them from flopping around into the line of sight of the laser.
And that's all there is to it. I've never assembled a kit 3D printer before, but it was a lot of fun and really easy to do. I'll be writing up more guides and articles about using the Peopoly Moai and setting up a workflow to go from model to masterpiece, so stay tuned for those.