Aluminum

[Mapster]

I just picked up an aluminum rod and went to make a black ti jr gent 2. Drilling was tough, but turning was rediculous. Four hours later I finished the pen, but I was wondering how I could do it easier. I have a woodchuck pro, but the aluminum kept melting on the insert making it dull instantly. I would then procede to chiseling that off and dipping in water, and starting again. I have a request for a slimline and I think it would take me a year to finish at that rate. Thanks for all help.

 

[BigShed]

Sounds like your RPMs were just a tad on the high side

 

[Mapster]

I turned it @ 2500 rpm, I figured faster would be better, but slower might be the key.

 

[Padre]

I have turned 2 of Johnnycnc's aluminum blanks now, one Sierra and one Baron. I used a regular roughing gouge and had my lathe (Delta 46-460) at the highest RPM. Worked great.

Now if I can just figure out how to get ALL of the scratches out, I'll be happy.

 

[Padre]

Oh, yeah, I also tried my carbide tool, and that did not work out so great. It chattered up a storm. But that was NOT with a new edge, it was on a previously used edge.

 

[DozerMite]

Sounds like soft aluminum. Try some 6061, it works great and can be turned with standard chisels. I believe John's blanks are 6061.

I just picked up an aluminum rod and went to make a black ti jr gent 2. Drilling was tough, but turning was rediculous. Four hours later I finished the pen, but I was wondering how I could do it easier. I have a woodchuck pro, but the aluminum kept melting on the insert making it dull instantly. I would then procede to chiseling that off and dipping in water, and starting again. I have a request for a slimline and I think it would take me a year to finish at that rate. Thanks for all help.

Proper buffing will make it shimmer like a mirror. It also makes it pretty slippery...

I have turned 2 of Johnnycnc's aluminum blanks now, one Sierra and one Baron. I used a regular roughing gouge and had my lathe (Delta 46-460) at the highest RPM. Worked great.

Now if I can just figure out how to get ALL of the scratches out, I'll be happy.

 

[ldb2000]

+1 for using 6061 Aluminum . I find that a slower speed works better , I turn aluminum at around 1100 rpm . Also scrapers , even carbide ones don't work as well , I use a Hunter carbide tool for the roughing cuts then a carbide tipped gouge for finer shaping and a carbide tipped skew and a shearing cut for final finishing .
For a slimline use 3/8" stock so there is less to turn away . I do several slimline style kitless aluminum pens and find that the 3/8" saves allot of time .
As far as finishing Aluminum , sanding is important , be sure to remove as much of the scratch pattern as you can then buff the pen at several different angles including length wise with Tripoli and white diamond . The buffing takes the most amount of time when making an aluminum pen but will give you a mirror like shine that will resist tarnishing and will only require an occasional light hand buff to keep it's shine .

 

[rogerpjr]

Not sure what alloy you got, but if you picked it up at one of the big box places it is probably 5052 or 6061. The piece should be marked with the alloy. As above, 6061 is a harder alloy than 5052 and will probably be better for you. Drilling shouldn't have been very difficult at all if you used a sharp HSS twist drill. You want to drill at a lower RPM so the bit doesn't grab. Clear the cuttings often and although you shouldn't need it for drilling the hole, use a lubricant.

Carbide likes higher rotational speeds as compared to using HSS, but these still aren't really fast. Besides the issue of being dull, you need the tool supported very firmly. The closer you can get the better. Also keep the side to side movements slow compared to turning wood or plastics. It may also help to use a little lubricant on the piece. When I'm turning Al on my metal lathe , what works best for me is plain old WD-40. you can either give it a quick spray periodically or squirt some into a small container and apply it by brush every so often. Try the lubricant at the higher end of the lathe speed and adjust down till you get it to turn off nice curls of metal. You shouldn't be getting chips flying off the piece if you have the conditions right.

 

[workinforwood]

yep, aluminum is a pretty soft and sticky material. I put some oil in a cup and dip the end of the carbide tool in it every so often. This stops the sticking to the tool. Also brush oil on the drill bit. It makes a big difference. If you get a little build up of aluminum on the drill bit, it can make the bit start to wander in the hole. When I finish aluminum, I just wet sand through the mm pads and then a dab of aluminum polish on a soft cloth almost instantly transforms the metal into a mirror, as well as helps protect the aluminum a bit. I do not worry about any other type of finish, like shellac's or powder coating. Although a shiny pen is nice, a worn, dull, used, aged pen is also nice.

 

[RAdams]

a bit of liquid dish soap in your wetsanding water will do miracles as well. This applies to plastics also.

 

[ctubbs]

The single best cutting fluid for Al I have found is (expensive now) water. It cools the metal and keeps it from melting. Best I ever found. Beats tap magic, WD40, Kroil, dark and light thread cutting oil.
Charles