Best Method for Cutting Heatsink



I have a heatsink that I need to cut to size and add tappings to (linked below):


Can anyone suggest the best machine to use for cutting something this thick with fins? I was thinking the plasma cutter might be the best to make the cuts and start the drill holes and then tapping on a drill press.


Thank you!
-Priyanka Das


Big no on the Plasma. It won’t get you what you want done. The vertical bandsaw would probably be the best to cut it. Either the Bridgeport or Drill press would make it easier to dril the holes required.


When I worked at a job shop, absent a slitting saw, band saw is the best way to use a bandsaw.

If cutting between the fins, no problem. Across fins, have a sharp blade and be gentle.


cutting heat sinks SUCKS. it kind of depends how you need to size it. If you have to modify the height of the fins they are going to want to bend. same if you cross cut against it. We generally run a sharp end mill at high speed (8-10k rpm) but you just can’t plunge into it. It has to generally ramp in which implies the use of a cnc. If you’re sizing it length wise and can cut between 2 fins - you got lucky.
Good luck.


There is some possibility to cut between fins, but cuts across the fins also need to be made. I do also need to make cuts in the middle of the heatsink through all fins for a clearance. I do also need to modify the height of a few fins in which case I may consider cutting the entire fin off. I do also need to make 8 tabs/flanges with tapped holes on this heatsink which I am not sure if it is possible?

I am seeing band saw as the only suggestion to cut the heatsink to size and the use of Bridgeport or drill press for the holes.

Would the HAAS or Shapeoko be out of question as well?


Given the complexity of the cuts you want to make I would get creative with your fixturing of the part and cut all the features on the HAAS.

I would try 3d printing a negative of the heat sink and lightly gluing them together. Then CNCing through the 3d printed support as well as the heatsink.

How thick are the blades on the heat sink? If they are around 0.1" thick you can probably get way with cutting on the HAAS without needing the 3d printed stabilizer.


The fins are less than 0.1" thick thank goodness! I appreciate all the help! I will begin signing up for HAAS training ASAP.


Get cozy with Fusion 360 beforehand.

It’ll help carry you from HAAS class 2 to HAAS class 3 (cutting a domino) faster/sooner.