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View Full Version : Cutting aluminium without oil/coolant



Desertboy
03-08-2017, 07:03 AM
Hi I'm going to fit an MDF bed to my router mostly because an ecocast bed will cost 583+vat which is over 1/2 what I spent on building the router lol. 95% of what I will process will be wood/mdf but occasionally I want to do aluminum (EG make plates for another router) but of course if I use coolant it will knacker my mdf bed.

I was wondering if people had success cutting aluminium using only compressed air to clear the chips? Speed will not be an issue so I could take it very slow and shallow cuts to compensate.

Thanks
Desertboy

Clive S
03-08-2017, 09:57 AM
I was wondering if people had success cutting aluminium using only compressed air to clear the chips? Speed will not be an issue so I could take it very slow and shallow cuts to compensate.
Plenty of people on here cut with air and a bit of mist etc https://goo.gl/photos/xVnL6vNar3rxUieU9

Desertboy
03-08-2017, 10:29 AM
Plenty of people on here cut with air and a bit of mist etc https://goo.gl/photos/xVnL6vNar3rxUieU9

What I'm worried is mist will damage the mdf, it's not exactly the best surface lol but it is a cheap wasteboard for wood cutting.

Clive S
03-08-2017, 10:41 AM
What I'm worried is mist will damage the mdf, it's not exactly the best surface lol but it is a cheap wasteboard for wood cutting.

I only use the mdf as a spoil board if I am doing anything that requires precision then I just surface skim it. the mdf that you see is on top of my bed

Zeeflyboy
03-08-2017, 11:53 AM
Moisture resistant MDF would be good anyway, should be less susceptible to changes in humidity. I think mist coolant could still mess with your surface though.

Phenolic/SRBP is a fairly commonly used bed material and is basically for all intents and purposes unaffected by moisture... but a large piece or two will still end up expensive.

However you can definitely machine aluminium completely dry. An air blast is good for getting some cooling but more importantly getting the chips out of the way to avoid recutting... when machining dry I found single flute to be the easiest with these high speed spindles.

I have done plenty of dry machining, but I must admit since adding coolant I've been able to push harder and use a wider variety of tools with success. There are guys doing some very successful and high speed machining dry though, so I imagine a lot of it comes down to experience and knowledge. Definitely easier for an amateur like myself if you throw some mist coolant into the mix.

Christian Knuell
04-08-2017, 09:41 AM
Hi,

I do almost all aluminum machining with trochoidal milling.
It works very well without lubricant and also without air:


http://www.youtube.com/watch?v=U7yn399bE1I

Christian

Boyan Silyavski
04-08-2017, 07:55 PM
The cheapest way to do it is to seal the MDF / paint it/ and on top of it use Expanded PVC sheet 5-10mm or even better use only paper filled or better type of phenolic sheet .

Desertboy
05-08-2017, 09:46 AM
The cheapest way to do it is to seal the MDF / paint it/ and on top of it use Expanded PVC sheet 5-10mm or even better use only paper filled or better type of phenolic sheet .

That sounds like a plan! I will have to wait a couple of months to afford it so will use an mdf board as a temp measure until then.

Next I need to buy 4 AM882's, a BOB & build a power supply, then upgrade the PC so I can run Fusion then finally I can afford the expanded PVC sheet (Or Phenolic) building a cheap ass router is expensive ha ha ha.

An idea I toyed with for a while is to take a small air tank (salvaged from a lorry) and put it in a cold water bath. Use a chiller to keep the water at 1C and then connect the tank to compressed air (With correct fitting of course) then I can charge the tank with compressed air cool the air down and then when uncompressed the air will be below freezing. Cooling the part whilst cutting it.

I would have to leave the air in the tank a good hour to cool down before using it so it's best to charge the tank then disconnect it from the main supply so it's not topping up with warm air.