[spalm]

Would you please help a newbie to metals understand aluminum type codes?

I am considering taking the plunge into aluminum for building my next machine. I am looking here.

What is the difference with 2024, 5052, 5083, 5086, 6061 etc? Is half inch a good start for something like a gantry or Z-axis structure? Tap it for 1/4” bolts?

Steve

[dano4406bbl]

Spalm,

I have refered to The Machinist's Handbook 25th Edition in the past when running into material questions. Here is a simple explanation of Aluminum alloy codes from the books. http://www.jjjtrain.com/vms/engineer...al_stds.html#6 I'm sure an Engineer can better answer your questions, but I hope this helps. I machine aluminum everyday, and have found 6061 to be one of the easier alloys to machine, as well as reasonably priced. 2024 is pretty expensive and other alloys can be "gummy" or brittle to machine and tap. Be sure to use a tapping fluid specifically for aluminum, or kerosene works too, but may be a bit dangerous. Hope this may be of some help.
Dan

[kinneycan]

I have found that you can get Alum in the 6000 range fairly cheap, at your local salvage yard.

They tend to cul these harder Alum, due to the fact that it is harder to recycle.

I have been paying $1.00 per pound, at lot cheaper than paying by the foot!

KinneyCan

[widgitmaster]

Hello Steve!

My favorite is 2024 because you can get it pre ground flat, its called MIC-6 or Jig-Plate. Because its nice and flat, everything builds up nice and square! Its easy to tap, and I prefer course threads like 1/4-20 and 10-24. A little WD-40 helps with the tapping too!

My 1st machine has 24x18 table, the bulk of the machine was built using 1/2" MIC-6. The X-axis slide block was hogged out of a piece of 6061 18x9x2" Due to the high cost of Linear Slides, I choose to use 1" diameter Thompson rails. They still flex a little, but it is much stronger than I expected!

As for the other alloys, the nicest to machine is 7075!

I sure wish there was a scrap yard in my area, I had to pay full price from Speedy Metals and eBay!

Eric

[mxtras]

Google aluminum alloys - tons of info.

7075 can not be welded....well - not very easily, anyway - in fact it is an absolute pita to weld. Just a consideration....

6061 and 6063 are likely the most popular alloys for structural application and extrusion and is readily machined and welded.

Scott

[MBG]

Get the t6 5-11 6061 it is the best to machine and like everybody sells it... haah it's all I cut..

[l u k e]

Here is a nice little write up from McMaster-Carr>>>

[spalm]

Thanks guys. Looks like jig plate will work nice for my Z. The half inch already comes in 7.5" strips and machinability is rated excellent. (But I'm sure the others would work fine also.)

L u k e,
Nice link. That's a good reference that I will hang on to.

Steve

P.S. looks like OnlineMetalSupply.com has become an eBay store since I first posted.

[dano4406bbl]

Just to clear things up, I was a bit confused to widgetmaster's response in stating that 2024 and MIC-6 are the same material. is this true or not? I thought MIC-6 is a material that is easily workable, and cheap, while 2024 is a very expensive and unfriendly material to work with. Just wondering.
Dan