What This Collection Delivers in Hard Numbers This is a family of round, radial-fin aluminum heat sinks—machined from solid 6061-T6 or 6063-T5 bar stock on 4-axis CNC lathes and machining centers. T
Get a quote
-
English
- sc@bquq.com
What This Collection Delivers in Hard Numbers This is a family of round, radial-fin aluminum heat sinks—machined from solid 6061-T6 or 6063-T5 bar stock on 4-axis CNC lathes and machining centers. T
This is a family of round, radial-fin aluminum heat sinks—machined from solid 6061-T6 or 6063-T5 bar stock on 4-axis CNC lathes and machining centers. The concrete benefit: you get a radially finned geometry that maximizes convective surface area per cubic centimeter, with a guaranteed outer diameter tolerance of ±0.01 mm and a critical runout of 0.02 mm TIR (total indicated reading) on the mounting face. Material hardness is 18–20 HRC (T6 condition), which gives you a stable thread engagement point for #4-40 to M6 hardware without stripping. Lead time is 7 working days for prototypes, 12 days for production batches. All machining is done in-house at our Dongguan factory—no outsourced finishing, no hidden steps.
Radial fins create a chimney effect. Air enters at the outer circumference and rises through the gaps between fins, drawn by the temperature differential. This means you can dissipate 15–25% more heat than a flat base of the same footprint, depending on fin height and pitch. Our standard radial geometry uses a 3.0 mm fin thickness and 6.0 mm gap, which is tuned for natural convection in LED drivers, IGBT modules, and rectifier bridges. If you need forced airflow, we can drop fin pitch to 4.5 mm for a 12% increase in surface area—but we recommend you test that configuration with your fan curve first. We machine the fins as a single piece from the base—no skived or bonded fins that can delaminate at 150°C.
We stock 6061-T6 and 6063-T5 in diameters from 20 mm to 300 mm. 6063-T5 gives you 5% higher thermal conductivity (209 W/m·K vs 201 W/m·K) but is softer (12–14 HRC)—use it for pure heat sink bodies. 6061-T6 (18–20 HRC) is better if you’re tapping threads or mounting heavy components. For the mounting surface, we machine a flatness of 0.02 mm across the full diameter and a surface finish of Ra 0.8 µm on the base, Ra 1.6 µm on the fins. If you need a mating surface for a thermal pad or phase-change material, we can polish to Ra 0.4 µm—this cuts thermal interface resistance by roughly 10% compared to a standard machined finish. All parts get a clear anodize (8–12 µm) as standard, which raises emissivity to 0.85 for better radiation heat transfer. Black anodize is available at no extra cost for orders above 200 pieces.
Every heat sink is checked on a granite surface plate with a dial indicator—we do not sample. We measure three things on 100% of parts: (1) radial runout of the outer diameter relative to the center bore, held to 0.02 mm TIR; (2) flatness of the mounting face, held to 0.02 mm; (3) thread depth and perpendicularity on any tapped holes, using a go/no-go gauge. Hardness is verified on a Rockwell tester for every batch of raw material we receive—we reject any 6061 lot that tests below 16 HRC after T6 aging. We also do a 100% visual check for burrs on fin edges, because a burr on a fin can scratch a mating PCB. Every part ships with a dimensional report (CMM data) in PDF and Excel format. You can also request a video of the inspection process for your specific batch—it takes us 15 minutes to film and send.
| Parameter | Value / Range |
|---|---|
| Outer Diameter (OD) | 20 mm – 300 mm (custom up to 500 mm) |
| Base Thickness | 3 mm – 20 mm (standard 5 mm, 8 mm, 10 mm) |
| Fin Height | 5 mm – 60 mm (radial, straight or tapered) |
| Fin Thickness | 1.5 mm – 5.0 mm (standard 3.0 mm) |
| Fin Gap | 3.0 mm – 8.0 mm (standard 6.0 mm) |
| Material | 6061-T6 (18–20 HRC) or 6063-T5 (12–14 HRC) |
| OD Tolerance | ±0.01 mm (machined), ±0.05 mm (anodized) |
| Runout (TIR) | 0.02 mm max (base to OD) |
| Surface Finish | Ra 0.8 µm base / Ra 1.6 µm fins (Ra 0.4 µm optional) |
| Anodize Thickness | 8–12 µm clear (black optional, no extra cost above 200 pcs) |
| Flatness (Mounting Face) | 0.02 mm across full diameter |
| Lead Time (Prototype) | 7 working days (no MOQ) |
| Lead Time (Production) | 12–15 working days (MOQ 100 pcs for standard sizes) |
Radial fins are thin—at 1.5 mm minimum thickness, they vibrate if you push too hard. We use a two-step roughing and finishing strategy on our CNC lathes. First, we rough out the fin profile with a 35° diamond insert at 0.25 mm depth of cut per pass, leaving 0.3 mm stock. Then we finish with a wiper insert at 0.05 mm depth of cut and a feed rate of 0.08 mm/rev, which gives us a consistent Ra 1.6 µm on the fin walls without tearing. For fin heights above 30 mm, we switch to a 4-axis machining center with a long-reach end mill (5:1 length-to-diameter ratio) and climb milling exclusively. This keeps the fin tips from bending away from the cutter. We also use a high-pressure coolant (70 bar) through the spindle to evacuate chips from between fins—chips that stay in the gap will scratch the next fin surface. If you need fins thinner than 1.5 mm, we can go down to 1.0 mm, but you must accept a 0.05 mm runout spec and a 10% longer lead time because we slow the spindle speed to 3,000 RPM to avoid resonance.
For machining advice specific to heat sink fin geometry, see our CNC cutting tool selection guide—it covers insert geometry for thin-wall machining. If you’re pushing tolerances beyond our standard ±0.01 mm, review our CNC machining tolerances guide to understand what’s achievable on a production basis.
Most customers need more than just fins. We can machine the following into your radial heat sink in the same setup—no second operation, no extra lead time. Threads: M2 to M12, tapped to 6H class, with a chamfer on the entry hole. Studs: we can press-fit stainless steel studs (M3 to M8) into the base—we hold perpendicularity to 0.05 mm. Grooves: an O-ring groove on the OD or base for sealing in outdoor LED housings—we machine it to standard AS568 dimensions. Center bore: we can make a through-hole or blind bore with a shoulder for mounting a TO-220 or TO-247 package directly. Counterbores for socket-head screws: standard. If you need a step on the OD (for a clip-on fan), we machine that too. All custom features are documented in your free DFM report—we send it within 24 hours of receiving your drawing.
Fins are fragile—a 1.5 mm thick fin will bend if dropped. We pack every heat sink individually in a foam-lined corrugated box, with the fins facing upward and a cardboard spacer sheet between each layer. For production orders above 500 pieces, we use custom-cut EPE foam trays that hold each part in a dedicated cavity—this prevents fin-to-fin contact during transit. Standard export packing is a 5-layer corrugated carton with a maximum gross weight of 25 kg per box. We ship via DHL, FedEx, or UPS for orders under 50 kg (delivery in 3–5 days), or via air freight (LCL) for larger orders. For sea freight, we use moisture-barrier bags with desiccant inside each carton—aluminum corrosion from humidity is a real risk on a 30-day sea voyage. We have shipped to the US, EU, and Japan with zero transit damage claims in the last 18 months.
No MOQ for standard sizes in our catalog—you can order a single prototype at the same per-unit price as a 100-piece order, and we’ll ship it in 7 working days.
Yes—we regularly machine custom OD diameters up to 500 mm, tapered fins, and asymmetric fin patterns; just send a STEP or DXF file and we’ll confirm feasibility and pricing within 12 hours.
We inspect 100% of parts on a granite plate with a dial indicator, and every batch gets a CMM report covering runout, flatness, and thread quality—no sampling, no exceptions.
Standard lead time is 12–15 working days from drawing approval, plus 3–5 days for shipping via DHL or FedEx to most global destinations.
Send your drawing (STEP, IGES, or PDF) to sc@bquq.com, or message us on WhatsApp at +86 13713157787. We will reply with a firm quote—including unit price, tooling cost (if any), lead time, and a DFM note on any risks—within 12 hours on a business day. The Round Radial Aluminum Heatsink Collection is precision manufactured in China at our Dongguan factory, with no MOQ. You can also browse our full range of custom CNC parts—if you can draw it, we can machine it. Send your drawing today and test our speed with a single prototype. We reply in 12 hours, not 3 days.
| Parameter | Capability |
|---|---|
| Materials | AL6063/6061/5052, pure copper C1100, copper-aluminum composite |
| Process | Extrusion, CNC machining, skiving, forging, die casting, stamping fins |
| Fin Types | Extruded, pin fin, skived, folded, bonded, heat pipe, vapor chamber |
| Surface | Black anodizing, clear anodizing, nickel plating, powder coating |
| Size Range | Max 1500 x 400 x 300 mm |
| Thermal Test | Thermal resistance and heat dissipation data per batch |
| Prototype | 5-7 days, no MOQ on samples |
| Inspection | CMM, thermal resistance tester, full report per batch |
