Yes, we can do aluminum....

[JerryBurks]

I am building a bigger CNC machine and I am using the Shark Pro Plus to machine the components. Most of the structural parts are actually made from bamboo plywood but I needed a few aluminum pieces for bearing supports and the like.

Since the question about aluminum come up here a few times I wanted to show some pics. I used mostly 1/8" 3-flute special aluminum end mill for outlines and holes and 1/4" same type for the circular pockets. With the shark I have to go quite slow but I got it to 3-4/1000" cutting accuracy. Parameters were 10ipm, 0.01"pass depth for the holes at 20krpm. For the cutout I used 20ipm, 0.015 pass depth , both in climb mode to make sure not to under-cut. For best accuracy I just ran the same path twice. After all, not really suitable for production work but quite good for one-off projects. I learned that it is almost impossible to drill holes in aluminum but routing the holes with a slightly smaller end mill works quite well and makes very clean holes.

Bearing mounts and motor brackets 1/4" 6061 aluminum:


Motor-lead-screw coupling 1.4" diameter 2011 aluminum (the bolt pockets are milled, the rest is turned on a wood lathe):

[Bob]

Jerry,
Thank you for the information on machining aluminum with the Shark. I will print out this information and pictures to keep in the operating manual, along with all the other information gathered in this forum.
Bob

[SimRacn]

Very nice!, now i need to build that bigger mach i knew we could do alum, i just hadn't got to that point yet. That is about what i was going to try for cutting speeds/feeds. the poor little colt just wont handle too much.
with my plex and the cutters from precise bits, am having to keep it down to max depth of .100 with the 1/4" and also finding that for precise holes it is best to run the path twice, or have a 'modified' tool dia. just a bit bigger than the original. such as .270 vs .250, do a roughing pass, then come back in with the correct size for the finish.

What are you using for lubricant? kerosene works very good, but a tad flammable. Have used it on bridgeports, by just brushing onto the cutter and surface. Does not have to be a lot, just enough to have some lubrication.

Thank you for sharing the pics and info!

charlie v.

[JerryBurks]

..........What are you using for lubricant? kerosene works very good, but a tad flammable. ......

Actually, the cuts are done dry and since I had to go very slow anyway because of machine flex that was quite feasible. The parts got only hand warm. I have heard about WD40 as a somewhat effective lubricant/coolant but not tried it. The nice thing about milling dry is that the chips don't clump together and clear the machined slots. I experimented with Isopropyl alcohol (I have a brushless spindle and work in a well vented garage) but the liquid makes the chips cohere and build up piles of aluminum grit.

[rungemach]

I might be worth pointing out that at those speeds and feeds it takes a long time to make a part.

Yes it is possible, but really really slow...
When I was making solid aluminum parts and router mounts for my shark, I was using 1/2 inch to 3/4 inch 6061 plate. A router sized through hole would take around 45 minutes to cut. Lots of passes to try to maintain reasonable accuracy, and lots of little aluminum chips that seem to defy dust collection attempts....

[JerryBurks]

I might be worth pointing out that at those speeds and feeds it takes a long time to make a part.

Yes it is possible, but really really slow...
When I was making solid aluminum parts and router mounts for my shark, I was using 1/2 inch to 3/4 inch 6061 plate. A router sized through hole would take around 45 minutes to cut. Lots of passes to try to maintain reasonable accuracy, and lots of little aluminum chips that seem to defy dust collection attempts....

Yes indeed quite slow. Cutting one of the bigger plates took easily an hour or more. Routing in wood is much more fun but sometimes it just got to be metal. And, since it is for one-off parts I don't care too much.

[basecircle]

Very Nice Jerry.Have you ever tried useing ANCHOR LUBE?As To lube as you are cutting.I use to use this on mills and lathes.You can brush it on while cutting.Of course any lube can be messy.Goolgle it .It comes in a squeeze bottle.Good job Basecircle

[mcharles]

Thanks guys I'll give it a try...I was told by the manufacture of the alum sheet that I'm using that the router RPM should be about10,000. Your cutting at 20,000 though....the control panel for the shark indicates the feed rate % and I was cutting at the slowest of 25%...how does that relate to ipm??? Mark

[Bob]

Mark,
Speed= How fast the router is spinning.(20,000, etc.) This is only affected by the dial on top of the router when used with the Shark.

Feed= How fast the router is being pushed through the material. (80 ipm, etc) The FRO (feed rate override) only affects feed rate. Feed and IPM (inches per minute) refer to the same thing. IPM can be set using the vectric tool selection panel. IPM can also be slowed down using the FRO.


Bob

[JerryBurks]

Thanks guys I'll give it a try...I was told by the manufacture of the alum sheet that I'm using that the router RPM should be about10,000. Your cutting at 20,000 though....the control panel for the shark indicates the feed rate % and I was cutting at the slowest of 25%...how does that relate to ipm??? Mark

High performance carbide end mills can do much higher speeds. I am using a 3-flute S-carbide end mill from SGS designed for aluminum and other non-ferrous metals and purchased from MSC Direct (in their "Metalworking Deals" catalog the price is much lower). According to their feed and speed chart a 1/4" cutter should actually run at 25,000 and an 1/8" one around 50,000 rpm. Feed rate for the 1/4" could actually be as high as 120ipm at that speed in pretty deep cut but obviously that is way beyond the capability of the Shark. The machine would need to be 10-20 times as rigid.

I found the light cuts at lower speed a usable compromise for hobby use.