How to print experimental apparatus parts for science fair participants

Q: What can LunarWerx 3D Print help with?

They run in a web browser and you use them on a website hosted on Cloudflare. One checkbox slows the first layer to 15 mm/s by default, and the maker says it then sticks to a clean plate without glue. The tools are free to use.

Step-by-step guide for science fair participants to 3D print experimental apparatus parts, with tools that can help and mistakes to avoid.

By TexHouse · 2026-10-24

TexHouse is published by the makers of LunarWerx 3D Print, Vector3D and MeshyDL, which are compared here alongside other tools.

Design the part, check it fits your printer bed, print a test piece, and verify it works before the fair. Tools that can help include browser tools for settings and test plates, plus slicers for preparing the print.

Option	What it does	Fee
LunarWerx 3D Print	Browser tools that work out ironing settings, check parts for injection moulding and design 3D-printable foam inserts ^[1]	Free to use ^[1]
Slicer software	Prepares the print file with layer height, infill, and support settings for the printer	Not published
Calipers	Measure the printed part against the design to confirm it fits where it needs to	Not published

What you need before you start

Before printing experimental apparatus parts for a science fair, have a few things ready. A working 3D printer with a clean build surface is the foundation; check that the nozzle is not clogged and the bed is level. A roll of the filament you plan to use is needed, because material choice affects how the part holds up under load. Calipers help measure the part against the design so you can confirm it fits where it needs to. Keep the design file open, because most adjustments happen there. A clean workspace is also needed, because dust and debris on the build plate change how the first layer sticks. Finally, have a way to send the print job to the printer, whether that is a slicer on your computer or a web interface. A notebook to record which settings worked after each print is useful, because apparatus parts often need small changes between attempts.

Step by step

Design the part. Sketch the apparatus component to the dimensions the experiment needs. Check that it fits on your printer bed and that no part is thinner than the nozzle can reliably print.

Check the design for printability. Look for overhangs that need support, thin walls that may warp, and features that must be watertight. A part that will hold liquid or pressure needs a solid, sealed structure.

Prepare the print file. Load the design into a slicer or a browser tool that works out the settings for your printer, material, and finish. Set the layer height, infill, and any special settings the part needs.

Print a test piece. Print one unit of the part and check it against the design with calipers. Look for warping, layer separation, and features that did not print cleanly.

Adjust and reprint. If the test piece has gaps or weak spots, change the settings and print another test. Repeat until the part holds up when you handle it the way the experiment will.

Print the full set. Once the test piece works, print the number of parts the experiment needs. Keep the settings the same so every part behaves the same way.

Check each part before the fair. Inspect every printed part for cracks, warping, or features that did not print. Replace any part that does not meet the design before the fair day.

Tools that can do it

Several tools can help with parts of the process.

LunarWerx 3D Print is made by the team that publishes this site. It provides browser tools that can help with ironing settings and other 3D printing tasks. ^[1] It runs in a web browser ^[1] and you use it on its website, which is hosted on Cloudflare. ^[1]

For ironing, it works out ironing settings for your printer, material and finish and exports a ready 3MF file. ^[1] It makes a 9-pad or 16-pad test plate around your settings, and you mark each pad as worked or not. ^[1] You can click flat top surfaces, and the export adds a modifier part over each picked surface. ^[1]

For an uploaded Bambu or Orca project, it adds ironing settings for each part and leaves the rest of the file unchanged. ^[1]

It also checks a part for injection moulding with 13 checks, shows shrinkage, pressure and weak-point maps, and builds the two mould halves; all numbers are estimates. ^[1] It lays parts out in a box and designs a 3D-printable foam tray and top pad that each part lifts straight out of. ^[1] The foam insert is split into pieces that each fit your printer's bed. ^[1]

When you open an STL file with faces turned backwards, it turns them right side out and says how many it fixed. ^[1] It runs only in your browser, and signing in lets your settings, recent test plates and print results follow you to every computer. ^[1]

The code package is marked private, not public. ^[1]

The tools are free to use. ^[1]

Common mistakes to avoid

Printing the full set without a test piece is a mistake. A part that looks right in the design file may warp, crack, or not fit when it comes off the printer. Always print one test unit and check it before committing to the full batch.

Using a material that does not suit the experiment is another common error. A part that will hold hot liquid or stand under load needs a material that handles that. Check the material's temperature rating and strength before printing.

Skipping the design check for printability is a mistake. Overhangs that need support, walls thinner than the nozzle can print, and features that must be sealed all need to be caught before the print starts, not after.

Not checking each part before the fair is a final error. A part that printed well on Tuesday may have a hidden crack that shows up under load on fair day. Inspect every part and replace any that do not meet the design.

Frequently asked questions

What can LunarWerx 3D Print help with?

They run in a web browser ^[1] and you use them on a website hosted on Cloudflare. ^[1] One checkbox slows the first layer to 15 mm/s by default, and the maker says it then sticks to a clean plate without glue. ^[1] The tools are free to use. ^[1]

How do you check a part before printing the full set?

Print one test unit and measure it against the design with calipers. Look for warping, layer separation, and features that did not print cleanly. If the test piece has gaps or weak spots, change the settings and print another test. Repeat until the part holds up when you handle it the way the experiment will.

What material should you use for apparatus parts?

Check the material's temperature rating and strength before printing. A part that will hold hot liquid or stand under load needs a material that handles that. The filament you already have on hand is a starting point, but verify it suits the conditions the experiment will put it through.

How do you fix an STL file with faces turned backwards?

LunarWerx 3D Print turns them right side out and says how many it fixed. ^[1] This happens when you open the file in the tool, and the result is a corrected file ready to print.

How do you keep settings consistent across multiple parts?

Print a test piece first and record the settings that worked. Use the same settings for every part in the batch. LunarWerx 3D Print makes a test plate around your settings, and you mark each pad as worked or not. ^[1] Signing in lets your settings, recent test plates and print results follow you to every computer. ^[1]