View Full Version : Which aluminum alloy would you recommend ?

02 December 2012, 1329
Hi guys,

I'm busy machining the parts for my battery box on my new mill, complete beginner, broke off one tool today. :mad:

I'm wondering if the aluminum alloy i bought isn't overkill for my purpose. I bought a 20 mm board of this:
EN AW-7022

Should i "downgrade" instead to :
EN AW-6082

thanks in advance for your guidance, before the newbie breaks more tools ....

Nuts & Volts
02 December 2012, 1450
6061-T6 is easy to machine, weld, and cheap. It is also strong enough for most of the loads our street bikes will see.

02 December 2012, 1530
Glad to hear you've got yourself a mill.
I don't really know much about those different grades of aluminium alloys but what I think you're asking is, is one grade easier to machine than the other? And I don't think that there is going to be a great deal of difference between the two to be honest. They will both have very similar machining properties.
It will take a bit of practice and a few broken cutters to get a bit of a 'feel' for milling so get kitted up with safety glasses and some machine guards, it makes you jump if swarf and end mills tickle your skin.
The trick with most aluminium alloys is a high cutter speed (RPM) and a high feed rate (this can help prevent what I kinda describe as ripping and clogging). It is easier to achieve this on small manual milling machines by taking a smaller depth of cut and using a cutter with fewer flutes.
It's a good idea to work out the cutter rpm for a guide if you haven't already, this will help put you somewhere in the ball park.
Think about the 'six degrees of freedom' when clamping your workpiece too, and the direction of the cutting force. It will all help towards not snapping tools and a better surface finish.

02 December 2012, 1717
Check out OnlineMetals.com's product guide: http://www.onlinemetals.com/productguide.cfm

Aluminum is here: http://www.onlinemetals.com/aluminumguide.cfm