FLsun SR led lighting

Warning! This model has a cooling issue, use the new version instead

After some time using this, I had to replace several leds that failed, most likely because of insufficient cooling, so I cannot recommend it, unless reducing the current further (already reduced it from 0.7A to 0.5A). I have made a new version using the aluminium extrusion as heat sink instead, which seems much better.

Original description

This lighting setup uses three powerful leds integrated in the printer's columns, below the  linear rails. It provides an effective lighting of the build plate, very useful to monitor the printing process, particularly the first layers. The leds directly illuminate the build plate, but are shaded on the sides and top to prevent dazzling (except if looking at the build plate very closely in an almost parallel direction, but in that case, the effector will likely shadow the direct light). The shades also add some complementary diffuse light by translucence. Access to the belt tensioners is preserved, as each assembly can just be slided downward as needed. Also, it doesn't ruin the printer's look, it's rather discrete when light is turned off.

A single white ABS part is used to hold each led and its heat sink together and is then clipped into the column. The same part also acts as a shade. . It should be placed roughly 10mm millimeters below the tensioning nut for ideal lighting.

Hardware

The design is intended for the following leds and heat sinks:

• https://www.amazon.fr/dp/B00LO2UBNY?ref=ppx_yo2ov_dt_b_fed_asin_titlehttps://www.amazon.fr/dp/B00LO2UBNY?ref=ppx_yo2ov_dt_b_fed_asin_title
• https://www.amazon.fr/BliliDIY-20X20X15Mm-Dissipateur-Processeur-Refroidisseur/dp/B07XZ56144https://www.amazon.fr/BliliDIY-20X20X15Mm-Dissipateur-Processeur-Refroidisseur/dp/B07XZ56144

The leds' connectors were flattened before soldering, and I used some electric tape to preved any short through the heat sink. The model could be adapted for different components with some work. I found that the heat sinks were actually too small (with passive cooling) for those leds at maximum current (700mA), so I reduced it to 500mA. Maybe it would make sense to use the columns' aluminium extrusion directly as heat sinks, but I'm not sure it's flat enough.

I used the following led driver:

• https://fr.aliexpress.com/item/1005009401790173.html

powered by the printer's 24V psu. It provides a 700mA constant current, but I removed the 0.5 ohm resistor (and left the two 0.4 ohms ones) to reduce the current to 500mA, after destroying two leds due to excessive temperature.

A 7mm diameter switch fits perfectly in the cooling holes. Wiring is easy through the large holes at the bottom of each column in the structure's base.

Printing

Use ABS (to sustain the heat) according to file orientation. Print slowly without supports, with two perimeters,30% infill, and 1.8mm skin removal width (in Cura) to help with the overhang.