# Router to cut Aluminium



## Sandyn (25 Sep 2021)

I need to cut a 10mm wide slot in a 6mm thick bit of aluminium. Has anyone used a Bench mounted router and really good TCT bit for this? I think I would secure the angle aluminium to a large bit of wood first so I can restrict it's movement and handle easier. Really light cuts. Any thoughts?


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## RobinBHM (25 Sep 2021)

A solid carbide spiral bit would do that.


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## gcusick (25 Sep 2021)

Carbide spiral upcut bit; lubricant (eg Trendwax); reduce the speed; fine cuts; hold everything very firmly!


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## Fergie 307 (26 Sep 2021)

For the light cuts you are talking about you could probably get away with an HSS end mill, although a Carbide one would be better. Good old paraffin is the best lubricant. Your problem will be speed, you really need to get it down to maybe 1000-1500 rpm. Or find someone who has a milling machine. If your slot goes right through then I would see if you can remove most of the material first using a jigsaw, so you are just using the bit for final sizing and to get a clean edge. The other issue is lubrication, you will need quite a bit to prevent spalling on the bit, not sure how you would do that on your router. You don't say how long the slot needs to be. Would it be practical to mount it on a pillar drill and just overlap the holes to get your slot, much easier to lubricate that way.


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## gcusick (26 Sep 2021)

Wealden (and Trend) do router cutters specifically for cutting Al. The edge profile is different from that of wood-cutting bits to reduce swarf sticking to the bit. I’ve not used them, but…


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## Lonsdale73 (26 Sep 2021)

gcusick said:


> Wealden (and Trend) do router cutters specifically for cutting Al. The edge profile is different from that of wood-cutting bits to reduce swarf sticking to the bit. I’ve not used them, but…



That's interesting because I asked Wealden this very question maybe two years ago and they said their bits weren't suited to cut aluminium.


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## Setch (26 Sep 2021)

Any cutter which will cut wood, will cut aluminium tolerably well. It will want to grab more, so you need to ensure your workpiece and any fences/guides are well clamped, but other than that just take multiple shallow passes and any straight router cutter will do fine.


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## gcusick (26 Sep 2021)

Here’s the reference:





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Aluminium 2 Flute Upcut







www.wealdentool.com


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## martin.pearson (26 Sep 2021)

Lonsdale73 said:


> That's interesting because I asked Wealden this very question maybe two years ago and they said their bits weren't suited to cut aluminium.



I noticed that Wealden increased the range of cutters they supply a while ago, not sure if they do a single flute bit but if you are using a router then a single flute bit would be better than a 2 flute bit. As has been mentioned slow the router speed down as much as you can use a lubricant & don't feed too slowly. if it's a one off then it may not be worth purchasing a bit & if you are careful then just about any wood bit will do the job if you take shallow cuts as has already been mentioned.


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## redhunter350 (26 Sep 2021)

Sandyn , last year I needed to put a rounded edge on some aluminium clamps I was making but didn’t have a suitable milling cutter so removed the bearing from a TCT router bit and used that - perfect result so no problem using a router bit on ally !


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## Sandyn (27 Sep 2021)

Thanks for all the very useful information. I will initially try an ordinary TCT cutter, but a new sharp one. I can lower the speed of my router, but only to 8000 RPM. I have been using my mitre saw to cut some of the aluminium, (70mm tube, 5mm wall). Was a bit apprehensive at first, but it worked very well.


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