Unusual metal machining process?

N_Cook · 2008-06-01T07:50:02+00:00

What would this process be called?Aluminium heatsink used for mounting electronic components to , to conductaway heat to the air . Some sort of chisell cutting advance and repeat whilestill hot after casting/extruding?, surely not done cold? steel rule laid across it,plus a close up showing the slightly angled cuts remaining uncut spine is about 4mm wide and the original bulk of metalmust have been about 9mm wide to be cut down, each side, to a 4mm spine.--General electronic repairs, most things repaired, other than TVs and PCs Devices, Southampton, England

Jun 01, 2008 28 Replies

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Paul K. Dickman 18 years ago

I've never heard skiving in terms of metal working.

In leather working skiving it the process of thinning the edge of a piece of hide, usually with a knife.

The process we use to put a glue splice in a flat belt is skiving. I it is also used to thin the edges so the seams in your shoes won't be two thicknesses. You use a knife to make a cut like you're filleting a smallmouth bass.

I envision a process like making a "fuzz stick" back in Boy Scouts.

A knife or a series of knives take a planing cut on the edge of the aluminum, raising a series of fins.

It would produce a piece just like the picture (the fins look way to thin for extrusions). It would be a really inelegant process though. The sort of thing I would expect from the third world.

I would also expect it to be a dead end technology .

Paul K. Dickman

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David Billington 18 years ago

After Ron(UK) mentioned the term skiving and I searched for "skiving metal" it turned up various links such as

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so why do you think it a 3rd world or dead technology.

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pkdickman 18 years ago

On Tue, 03 Jun 2008 01:16:39 +0100, David Billington wrotD:

Impressive. Understand, however, when I said dead end I didn't mean that it was the equivanent of the stone axe.

Just That I could only see it being advantagous for one use.

It is like a machine for making files. It does one thing really well but it is not much use for any other.

Paul K. Dickman

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Steve W. 18 years ago

It's a process called Skiving.

Basically they use a thin sharp knife to slice each leaf from the base metal. Been used for years for heat sinks and such. The machine that does it looks like a shaper with a wood chisel for a tool. It pulls back, gets a bite and skives up one fin. Then it cycles and skives the next.

The advantage is that it's fast, cheap and once the tools are set up you just change the cutter and go.

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Ed Huntress 18 years ago

That's interesting, Steve. I've never heard of it before, but I guess I'm getting further behind all the time.

One of the first articles I wrote for American Machinist was about skiving -- the older kind, done on a lathe. Making the tools was a hot new application for those brand-new inventions, wirecut EDMs. But the turning kind of skiving probably had its big day in the 1940s and '50s, before fancy profile grinders and multi-axis wire EDM made it practical and fairly cheap to make complex form tools with top rake and proper clearances.

-- Ed Huntress

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RogerN 18 years ago

Found some websites with pictures.

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RogerN

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przemek klosowski 18 years ago

I have seen heatsinks done by pressing in fins into a grooved/slotted base. The grooves are then swaged shut:

direction of the swaging |F | /

-------+|I |+---------- ||N || |+--+| BASE +----+

When you look at the side of such item, you can see the slots and maybe even the displaced material where the swaging pressure was applied.

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N_Cook 18 years ago

The roots of the fins are perfectly clean, also the 5 degree or so cut angle is still evident. I am convinced it is this skiving process, just leaving the question of whether it is done at the time of billett extrusion , so still hot, or done cold.

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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