BOM
The total cost to build an OpenCAL printer is approximately $1,638 (as of 6/2026).
Click the following link to view the Bill of Materials (BOM):
NOTE:
The first tab is for the total inventory. This is what you will realistically spend.
The second tab is for the used inventory. This is the actual cost of the printer.
The third tab is the analysis, allowing you to see the breakdowns of the printer by category.
SOURCING TIPS:
Many of these items can be found cheaper elsewhere, sourced locally, or reused from parts you already have in your workshop. The listed prices are a guide, not a requirement, so shop around before buying.
For the Amazon links specifically: these sellers frequently go out of stock or have long shipping times. Many other sellers on Amazon offer the exact same item, so if a link looks unavailable or unreasonably priced, look around for an alternative. If you find a better link, feel free to share it in the Discord so others can benefit.
Warning
T-nut compatibility (Frame section): several builders have reported that the flat slide-style nuts bundled with the 90° gusset bracket kits do not fit the recommended McMaster-Carr 20x20 aluminum extrusions (they do fit the Amazon-sourced short rails). The drop-in / hammer-style M5 T-nuts — the curved ones with serrations, listed as their own BOM line — fit all of the recommended rails. Use those for every T-nut position in the build, and treat the nuts that come with the bracket kits as spares. A builder-verified option is this 150-pack of 2020-series M5 hammer-head T-nuts.