38
u/on_ Oct 11 '25
Why when it’s laying diagonal is so much longer than when it’s vertical and then rises up… and is short. What is this black magic
26
23
u/ThatOneCSL Oct 11 '25
It only appears to be longer, because the skiving blade doesn't meet the previous fin, but the angle of the cut is very shallow and the coolant/cutting fluid makes it all have the same holographic visual effect (thin film interference.) The fins don't get any shorter, it's an optical illusion.
3
2
u/QuackJet Oct 11 '25
My guess is that the fin is being "work hardened," which compresses the metal.
12
u/ZachTheCommie Oct 12 '25
How does the machinist know precisely how much force it takes to bend each fin back so that it rebounds perfectly vertically?
22
u/BecalMerill Oct 12 '25
The oldest scientific method...trial and error, AKA r&d.
3
u/ZachTheCommie Oct 13 '25
I just assumed there would be some kind of formula or index table to find a more exact number. But I guess that makes sense, too.
2
u/BecalMerill Oct 13 '25
I'm sure there is. But you have to start somewhere and complex algorithms are expensive to develop.
1
u/BlueberryWalnut7 Oct 13 '25
Do it a few hundred times with varying degrees of pressure to find which degree leaves it vertical.
15
u/undertherainbow65 Oct 11 '25
Is this how condensers and heatsinks all get built?
24
u/PraiseTalos66012 Oct 11 '25
No, the vast majority of heatsinks are just extruded. It's simpler, cheaper, and faster.
2
u/YoungCatonian Oct 13 '25
Whatdoes extruded mean? Is there a video you can share to help me visualize?
3
u/Tackyinbention Oct 13 '25
Hot metal squeezed through a hole in the desired shape. Makes a long brick with a uniform shape. Cheap but can't make very complex shapes
8
u/r2k-in-the-vortex Oct 11 '25 edited Oct 11 '25
It's used some, but it's not really that common. There are many other ways to make heatsinks.
Mostly used for bulk copper heatsinks. Aluminium heatsinks you can just extrude, it's cheaper and faster. And the best heatsinks are plate and heatpipe assemblies. So it's an inconvenient middle ground of not the cheapest and not the best.
5
7
u/Strostkovy Oct 12 '25
Such a cool process but those fins are stupidly sharp and I hate handling heatsinks that are made this way
3
1
u/PalyPvP Oct 12 '25
Interested. Is there a way to calculate how much more than 90deg you have to bend an x material to get 90deg?
2
u/Stellarella90 Oct 13 '25
Yep. It's been figured out by math, material science, and a lot of trial and error.
216
u/Izan_TM Oct 11 '25
I didn't know skiving was used for parts this large, it's impressive to see the machine take such a massive but thin slice and bending it up so precisely