Custom LED Heat Sinks —
CNC Machined Aluminum

Designing an LED fixture and the catalog heat sink doesn't fit your board or your wattage? EKINSUN machines a custom aluminum LED heat sink to your exact LED/COB footprint — no extrusion die, from 1 piece. Quote in 12 hours.

An LED Heat Sink Matched to Your Board

Off-the-shelf LED heat sinks come in fixed sizes and hole patterns — great until your COB, MCPCB or star board doesn't line up, or the thermal budget needs a bit more fin. We machine the heat sink to your LED instead: the correct mounting holes, a flat lapped contact face for the thermal pad, and the fin area your drive power requires. Because it's CNC machined, not extruded, there's no die to pay for and the minimum order is one piece — ideal for a prototype fixture that later scales to production.

Sizing by LED Power

The right heat sink depends on drive power, ambient temperature, orientation and the target junction temperature — but as a starting point:

LED power	Typical approach
1–3 W	Small finned block or star heat sink, passive
5–20 W	Finned plate, natural convection, black anodized
20–60 W COB	Larger finned body; pin/blade fins, sometimes active
60–150 W+	Heavy finned mass or active/liquid — high-bay, streetlight, grow light

Send us the LED, the power and where it runs, and we'll size and quote it — no thermal-engineer required on your side.

LED Applications We Machine For

Material, Finish & Mounting

• Aluminum 6061 / 6063 — 6063 for fin-dense bodies, 6061 for machined heat sinks with mounting features and driver pockets. Copper for extreme flux.
• Black anodized — raises emissivity for better radiative dissipation and protects the surface; clear and colored also available.
• Flat lapped contact face for the LED/MCPCB thermal pad or paste, tapped holes for the star/COB holder, and an optional pocket for the driver.

Grade choice on an LED sink trades conductivity against strength and machinability. Two grades customers ask for regularly are the wrong answer here:

Material	Conductivity / density	When it belongs on an LED heat sink
6063	about 201 W/m·K	Highest conductivity of the common structural grades. Use it when the part is mostly fin and the mounting features are plain through-holes.
6061-T6	about 167 W/m·K · 2.70 g/cm³	34 W/m·K less than 6063, bought back in thread strength. Use it when the body carries tapped holes, a driver pocket or a bracket ear.
7075-T6	about 130 W/m·K · 2.81 g/cm³	Thermally a step backwards. 130 against 167 W/m·K, and heavier at 2.81 g/cm³. Only justified when the sink is also a loaded structural part. If it is just a heat sink, 7075 costs more and cools worse.
Stainless 304 / 1.4301	about 16 W/m·K · 7.93 g/cm³	Ruled out on conductivity. Roughly a tenth of 6061-T6 and nearly three times the mass. Correct for an outdoor bracket or a housing that bolts to the sink, never for the sink body itself.
Copper C11000	about 388 W/m·K · 8.96 g/cm³	COB flux that aluminum cannot spread fast enough. Machinability index 20, so it cuts slowly, and 3.3× the density of 6061 — worth it as a spreader plate under the die, rarely as the whole body.

What the LED Catalogue Already Covers — and What It Doesn't

Round pin-fin coolers for standard star boards are a solved, stocked product. The gap is a sink matched to a board outline and hole pattern nobody stocks. Where the catalogue wins, buy the catalogue:

What you need	In the catalogue?	What we do about it
Round pin-fin cooler, Ø50–Ø90 mm, for a standard star board	Yes — a stock cooler body on a standard star pattern is a catalogue item	Buy the catalogue part. A stock cooler ships from stock and beats a machined one-off on price at any quantity. Don't send us this drawing.
Same fixture, but the board is a 46 × 28 mm rectangular COB carrier with holes on no standard pitch	No — a stock cooler is drilled for the pattern it was designed around, not for yours	Machined base to your outline, mounting holes on your pitch, flat lapped contact face for the pad, tapped holes for the holder. MOQ 1.
0.60 mm fins, 20 mm tall (33:1) to fit the fin stack inside a Ø70 mm can	No — extruded profiles start about 1.20 mm and run out near 12:1, with 1–2 degrees draft per side	Not milled either: milled fins stop near 8:1, from about 1.00 mm. Skived fins reach about 40:1 at 0.20–1.00 mm in 6063, 1050, C11000 or C10200; bonded fin passes 50:1 with 0.30–1.00 mm rolled sheet in a machined base, no tooling, from 1 piece.
Driver pocket, cable slot and two M4 tapped holes in the back face	No — an extrusion is one constant section, so anything that breaks the section is a second operation on the stock bar anyway	Cut in the same setup as the LED face, so the pocket and the contact face share one datum.
500 pieces a year of a plain finned bar, no back-face features, cut to length	Yes — a standard extruded profile cut to length, stocked deep by Fischer Elektronik, Aavid and Alutronic	You don't need us. At that volume with a constant section, stock extrusion cut to length is cheaper than machining and we say so on the quote instead of taking the order.
5 prototype fixtures now, 300 next year, same geometry	No — not in this outline without cutting a die first	No die, no setup fee, 1 piece. The same program runs the 300 when the fixture ramps.
Fin field stepped down on one side to clear a reflector skirt	No — a die produces one constant section end to end	Machined: fin height varies along the body, and the step is cut with the mounting face.

When not to ask us. If the LED sits on a standard star board and the housing has room for a stock round pin-fin cooler, buy it off the shelf — no machined one-off will match that price. Same answer for a plain extruded bar cut to length in volume with nothing in the back face: buy the profile, which Fischer Elektronik, Aavid and Alutronic stock deep. We earn the money only when the board outline, the hole pattern or the fin geometry is not in anyone's catalogue.

Frequently Asked Questions

Related: which fin type do you need? · all custom aluminum heat sinks · CNC milling · order from a sketch · all custom parts