1.0mm 2 flute cutter HSS or Carbide.

I have a good number of 1.0mm wide through slots to cut in 0.8mm 1050 alu sheet.

Top speed on my mill is 2500 which is obviously slow for a 1.0mm cutter but I did try a 2.0mm (smallest I have) HSS yesterday and it seemed to cut ok.

I am wondering do I go with HSS as it should be a bit sharper and 1050 is quite a soft material plus the speed will be down, or with such a small cutter would Carbide be a stronger tool and give a bit better feed rate.

It's a light duty job and there may not be anything much to choose between them..?

Ron

Edited By Ron Laden on 23/08/2020 08:58:08

I cut a 1.5mm slot in multiple passes in brass with a 1mm carbide cutter on my big mill recently with no drama, at about that speed. But I'm not sure about 1050 machinability, I often find ali sheet is very sticky and difficult to mill. I happily use 1mm cutters at 5000 rpm in the CNC though mainly on brass. I haven't used HSS cutters that size but the carbide ones seem just as sharp.

Rather you than me; 1050 is absolutely horrid to machine as it's essentially pure aluminium. It behaves like soft fudge, but doesn't taste as good. It moves rather than cuts and leaves large burrs.

I'd buy the cheapest HSS cutters you can find, as you'll be breaking some of them. There's no advantage in using carbide and unless they're highly polished carbide might be more prone to BUE.

Andrew

Yes try cheapo decent HSS & make sure you use lube to deter build up of material on the cutter

Tony

From the comfort of my Armchair I looked up a dozen Aluminium alloy Datasheets and found only one claiming 'good' machinability in sheet form. It's 6082. 3103, 5251 and 6063 are 'average' or 'acceptable'. All the others highligted machinability as 'poor', including 1050. Not a good choice.

Many metals are optimised for purposes other than being machined. Most aluminium alloys are rated 'excellent' for rolling, extrusion, cold working, soldering and welding. Great for window frames and sheet metal work but not meant to be machined. Expect bother.

My limited experience suggests the bother with Aluminium is mostly down to it's squishiness and low melting point. Tearing, smearing, distortion, and a high risk of swarf welding to the tool. Palliatives; high speed, sharp cutter, plenty of paraffin, and clearing swarf aggressively. Also worth experimenting to find the combination of depth of cut and feed rate that produces best results.

HSS vs Carbide - difficult to say. As neither of them can be spun fast enough for this job on a 2500rpm mill, I'd go for the cheaper option, hoping that HSS might be sharper. Mainly though, I don't think Carbide offers any advantage for milling soft Aluminium, and being brittle might cause expensive breakages. It's the gooey material that suggests HSS - milling fibre-glass in same way, I'd recommend carbide.

Dave

Thanks for the advice guys, looks like I need to change material for something more machinable. I will see what's available in 0.8 though I can go to 1.0 mm if need be.

Ron

Hi Ron, if you get a 1mm carbide one, don't drop it, don't ask why, but I bought one once, got it out of the container but it didn't make it to the collet.

Regards Nick.

Slitting saw or a couple of hacksaw blades side by side, power hacksaw blade?

Can't you make a punch and die and crop the holes? Far easier than clearing the cutter teeth.

Regards Ian.

6082T6 will be a much better choice. It machines very well although a squirt of WD40 may be needed to avoid the swarf sticking to the tool.

Andrew

Thanks Andrew, 6082 it is didn't realise 1050 doesn't machine well.

Going to go up to 1.2 mm maybe even 1.5 mm if I can find a supplier who offers cut pieces in 6082 they all seem to do 1050 in the smaller thickness and I only need a couple of square feet.

Ron

As mentioned 1050 is almost pure aluminium. As far as I'm aware it's only available as sheet. I've used it a fair bit for sheet metalwork as it bends nicely without cracking, unlike some of the alloys. But due to it's horrid machining characteristics it's one of the few times I use old school marking out with hand drilling and filing to work it.

SoD seems to have looked at a rather odd selection of alloys. The other common alloy, 2014A (aka HE15), is listed as excellent for machining.

Andrew

Keeping the sheet flat will be a nightmare while it is machined. In industry, a vacuum plate would be used. I would go for HSS and buy several,making sure that a lubricant like WD40 or AC90 was used at all times.

I have used 'double sided tape' to good effect, WD40 or AC90 is likely to soften the adhesive so a type of soluble oil would be needed if going down this route.

Tony

Superglue to a bit of metal, boil after machining

Obviously a 1.00 mm cutter is small but having received the ones I ordered and seeing them in the flesh it's a bit scary how small. I am trying to pluck up courage to give one a try.. ​​​​​​​​​​​

Better make sure you sit down before looking at a 0.5mm cutter then!

Andrew

I recently did some milling in brass with a 1.5mm cutter.

My mill speed is way too slow for such a little tool so mounted a Dremel on the side of the mill head and used the table DRO for positioning the job.

Paul.

Edited By Paul Lousick on 27/08/2020 11:00:56

The fine detail:

What surprises me is that the flutes seem somewhat longer than quoted.

Andrew