Starlight 4

Open Source Starlight Series Mini Laser Engraver - Starlight 4

• Notice: Due to the supporting motor for this open-source project being taken away by a mysterious person, to allow more people to replicate the mini laser engraver, I have updated and open-sourced the design for a new motor model - Starlight 4S. If you plan to replicate it, please go to this new projecthttps://makerworld.com.cn/zh/models/1227220-xing-guang-4s#profileId-1307219
• If the previously matching motor model can be found later, I will change the notice again! Date: May 16, 2025

Open-source model print files and modeling files (downloadable from the web) are available. Aside from the 3D printable models, all open-source related materials are on the Lichee Open Source Hardware Platform, and PCBs can be prototyped for free at JLCPCB. You can DIY a high-value mini laser engraver for a low cost of 70 RMB

Assembly videos have been uploaded to both Douyin and Bilibili. It is recommended to watch Douyin for higher content concentration. Douyin username: 流浪的星星; Bilibili username: 流浪的星星-dy

Assembly video Douyin link: 4.61 Copy and open Douyin to watch 【流浪的星星的作品】Starlight 4 assembly video https://v.douyin.com/i5Wgcgf6/ eoq:/ K@w.SL 10/18

Model printing parameters:Recommended layer height below 0.15mm, slow down the print speed. Commonly used materials like PETG or PLA are fine, I usually print with PETG because of its better toughness. Other parts can be printed as usual (0.2mm layer, 3 walls, 15% infill, 3 top and bottom layers). If only the laser head fixing bracket needs support, other printed parts do not require support

The hole where the slider passes through the optical axis needs internal burrs removed. It is recommended to use a 3.05mm twist drill to ream it for a smooth finish

Here is an accurate bill of materials for everyone. The circuit principle is intuitive and simple, and everyone can explore it themselves (you can also directly choose a finished mainboard; detailed solutions can be found on the Lichee Open Source Platform, MakerWorld only publishes open-source model files)

1. Prototyping PCB ×1, FR4 double-layer. Choose other non-chargeable options as you see fit

2. Arduino Nano development board ×1, ATmega328P chip. 9-12 RMB each, free shipping

3. A4988 stepper motor driver ×2. Unit price 3-3.5 RMB each, total cost 7 RMB (you can buy related electronic components from one supplier to save on shipping, wholesale components usually have lower unit prices and do not include shipping, no further details below)

4. N-channel switching MOSFET model IRFZ44N ×1, TO220 package. Four to five mao each

5. Three-terminal voltage regulator model LM7805 ×1, TO220 package. Three mao each. TO220 heatsink ×1, M3*4 screw ×1. Used in combination with this voltage regulator, total cost about 1 RMB

6. F3 LED ×2. One for power indication, one for laser signal indication. Unit price around 0.03 RMB (not essential, optional)

7. 1/4W plug-in resistors: 4.7Ω, 47Ω, 2K, 10K, 100K, one of each (unit price 0.01 each, but usually sold as 100 for 1 RMB)

8. XH2.54 terminal block (female): 4P straight pin ×2, 2P straight pin ×4. One 2P can also be replaced with a bent pin for Starlight 4 (worthless, 0.02 each, buy as you please)

9. DC female socket 5.5*2.1 pure copper ×1 (over one mao each)

10. Through-hole electrolytic capacitors: 16V100UF 5*7 specification ×2, 16V470UF 8*12 specification ×1 (a few fen each)

11. 2.54MM straight female header 1*8P ×4, 2.54MM straight female header 1*15P ×2 (about one mao each)

The above are all the components required for the mainboard, all are plug-in type, convenient for beginner soldering, total cost around 20 RMB

IV. The following are other parts required for assembling the mini laser engraver

1. Laser head 5V 250mW, 12mm diameter (about 23 RMB each)

2. Laser goggles (about 3 RMB for one, about 1 RMB each if buying multiple)

3. Data cable (compatible with the development board data interface, the cost of the development board is included in the mainboard cost, actually just buy it with the development board, about 0.5 RMB each, there are also Type-C development boards, same as mobile phone data cables)

4. Frame set (model STL files uploaded, those with a printer can print it themselves, material cost a few RMB, those without a printer can refer to my handmade version tutorial, or contact me to get the frame and full set of scattered parts and finished products, ps: a small source of income for crafters)

5. Matching screws: Starlight 4 matching screws: M3*4 (four pieces), M2.5*10 (four pieces), M2.5*8 (ten pieces), M2*4 (four pieces), no nuts needed (worth a few mao)

6. Mini stepper motor ×2, 58mm long lead screw, 3.75mm pitch, 1.2 RMB each. This motor is from Shenzhen Jiesheng Motor (sells inventory, I don't know them, no partnership). They sell an original imported Nidec 15MM two-phase four-wire mini stepper motor - Model C, said to have four to five thousand in stock. The drawback is that they don't offer free shipping, and the shipping fee is 6 RMB. Those who are clumsy can buy a few more for a better deal

7. Motor wires: cut a mobile phone data cable (a broken one is fine, don't waste it) and connect it to the motor

8. Stainless steel optical axis 3mm diameter, 10cm long, 50 pieces can be bought for 7 RMB, but only 4 are needed to assemble one machine. I prepare kits long-term, so I buy a lot, you can also look for retail options

9. Grease (butter-like substances are also okay, but I use 3D printer grease, perhaps other lubricating oil also works, without lubrication it's not smooth)

10. Power supply 12V 2A power supply (about 5 RMB each), the power input port needs to be 5.5*2.1 or 2.5 to match the mainboard's DC female port, using 2A is considering power supply mislabeling, if not mislabeled, 0.5A is enough

With all materials, the total cost for replicating the entire set of materials is approximately 70 RMB. The software is also open source, materials are shared free of charge, with no other paid content

I recommend downloading the model from MakerWorld to let me earn some points, haha, feels like begging t.t

If there are any omissions in the open-source content, please contact me for corrections, thanks