Hi Everyone,

We are located 'Down Under' and would really appreciate some information and feedback on what would be the best CNC profile cutting 'type' machine for 3mm & 5mm Aluminum. Not that happy with the cut by Plasma we've seen so far.

Any assistance on the ideal machine would be excellent.:banana:

Cheers

Brandon

Brandon,

I have parts cut by waterjet and they come out OK. i think it also makes a big differance at what speed they run the machine. For my own parts i cut it all on the cnc mill and prefer vacuum for holding plate down - i'm a sucker for surface finish.

I know Unabiker does a lot of parts from ali sheet on his home made cnc router and he's got a good way of keeping the plates down also.

Hopefully he would come on board and give you some tips.

Good luck
Pieter

Hi Brandon

i cut a lot of aluminium on a multicam cnc router.
From 1mm to 20mm sheet. I have found it is all about the cutters you use and the fluid used for coolant. I have been using Multicam routers since 2001 and I couldn't be happier. If you need more info. reply to this,More than happy to help. I'm based in Bairnsdale Victoria
Cheers Mick

Hi, I have had 100% success having it water cut and extremely accurate. contact me if you are in Sydney and I will give you a phone number of who I use ... Steve

Brandon,

Don't lump all "plasma" cut capability in one category! There are entry level air plasmas that many use on CNC machines....then there are mid level conventional industrial plasmas....and on top of the performance curve are high definition class plasma. Further...the cnc machine and the z axis (torch height control) are critical to providing good cut quality on aluminum or any material for that matter.

Air plasma....on a machine with decent acceleration and accuracy, and a good height control system can cut aluminum very fast....but with typical cut accuracies in the plus or minus .025" range (sorry for the imperial measure)....where high definition plasma can hold tolerances down to .010", and will provide better metalurgy on the cut edge.

Best regards, Jim Colt Hypertherm

Hi Brandon,

I use a homemade cnc router for cutting ally plate from 2mm to 20mm thick. A high feed rate (1000mm/min) and a small stepdown (1mm) works well for us with single flute carbide endmills. We could probably increase both of these if we installed some sort of coolant or misting system. This gives a much squarer cut than waterjet cutting that we have had done. Will leave pretty sharp edges though and you will need some way to hold the parts down (or leave tabs when you cut them out).

Regards, Leigh

Hi Everyone,

We are located 'Down Under' and would really appreciate some information and feedback on what would be the best CNC profile cutting 'type' machine for 3mm & 5mm Aluminum. Not that happy with the cut by Plasma we've seen so far.

Any assistance on the ideal machine would be excellent.:banana:

Cheers

Brandon

Dear Mr.Brandon
Laser cutting or water jet cutting will be the best.
Thanking you
Pradeep R.Khare
INDIA

Hello Brandon

I have little experience in cutting aluminium but recent parts cut in brass with both water and laser cutting suggest that water is better when the parts are harder and laser can be very accurate but if the parts is hardened by rapid heating and cooling (as high carbon steel) then it is unsuitable. The water cut brass sufered from a tapered cut which I estimate to be close to 5 degrees, I would check for something similar in aluminium.

Regards

Richard

Hi Brandon,

I use a homemade cnc router for cutting ally plate from 2mm to 20mm thick. A high feed rate (1000mm/min) and a small stepdown (1mm) works well for us with single flute carbide endmills. We could probably increase both of these if we installed some sort of coolant or misting system. This gives a much squarer cut than waterjet cutting that we have had done. Will leave pretty sharp edges though and you will need some way to hold the parts down (or leave tabs when you cut them out).

Regards, Leigh

Leigh, are you using a Porter Cable type router for a spindle? I have a small K2 machine with a PC router on it, I want to try cutting ally but I'm kind of scared to.

we use a turret on alum in that range. you will see nibble marks but the speed and accuracy is great.

Attached aresome pics of various thicknesses of aluminum....as cut with plasma. Very fast speeds....virtually no dross. A slight oxidation effect on edges, and a slight taper.....but the speed cannot be beat if you need parts fast!

From left to right..3/4", 1/2", 1/4", 1/8" and 1/16".

Jim

Leigh, are you using a Porter Cable type router for a spindle? I have a small K2 machine with a PC router on it, I want to try cutting ally but I'm kind of scared to.

Hi there. We used to have a GMC router on our machine (straight from the hardware store) and cut a lot of aluminium with that. We have now upgraded to a Chinese water cooled induction type spindle with a VFD for speed control (much quieter). The new one works a lot better with tiny cutters (0.3mm engravers and small single flute endmills) due to reduced runout but the old one was fine with anything 5mm or larger. If you take small cuts and keep a little lubricant up to the tool the router won't be under all that much load. Give it a shot! I'd definitely recommend the single flute endmills though. They seem to work a lot better on our machine than any others when cutting ally.

Frenzal - thanks for your response. I will definitely give it a shot. I'll start with a single flute and setup a coolant system.

Attached aresome pics of various thicknesses of aluminum....as cut with plasma. Very fast speeds....virtually no dross. A slight oxidation effect on edges, and a slight taper.....but the speed cannot be beat if you need parts fast!

From left to right..3/4", 1/2", 1/4", 1/8" and 1/16".

Jim

Jim, Thanks for the photos, those alum. parts turned out pretty good. Also I think different kinds of alum. cut better or worse than others. I know that the 2000, 3000, 4000, 5000 series is alot softer than 6061 or higher. This is why router bits have problems cutting soft alum. b/c it gets stuck in the flutes and your bit then turns into a rotating shaft. Thats why a single flute, low rpm, oil mist is the best, the alum. mush wont clog the cutting edge on the bit. When a router bit is cutting harder alum. it doesn,t usually stick to the bit (has nice chips) but takes alot longer to cut.... I love the edge quality of a router but you cant beat the speed of a plasma...time is money...

we cut alum at 1500mm/m with single flute 1/2" end mill, 14000 rpm, oil mister, 5-10mm doc this is on a multicam router

Hi Jim.
Thanks for your information/ The cut looks great and it's good to see the thickness ranges. What specific Aluminium is this?
Cheers

Hey Bud by a kovakon great machine for around10.000 $ give them a look

Laser gives a great edge finish and virtually no taper. On thicker materials you can end up with a small, soft burr on the bottom edge, but up to 5mm this is not really a problem. accuracy is within 0.2mm. Our 5.2kw machine will cut up to 12mm thick ally.

Waterjet would be by far the most desirable in production. No fixturing essentially if your just cutting flat stock. Your biggest concern would be pressure. The higher the pressure, the faster the feedrate and straighter the cut without striations.
Laser, plasma and milling, ALL change the material and leave a bur! Waterjet does neither. You can easily hold +/-.001"

Waterjet is not the only process desireable for production. Laser and plasma have their advantages as well.

Waterjet is great for an edge that is not affected thermally.....yet water jet capital equipment cost and operating costs are extremely high...and productivity (cut speed) is low. Tolerances with waterjet are closer to .004 to .006.....you would be hard pressed to produce 1000 parts that were all within .001" of each other!

Plasma is the fastest and least expensive with tolerances in the .015" to .030" range

Laser is reasonably fast, yet often has difficulty with the surface reflectivity on aluminum...parts are two to 3 times the cutting cost of plasma, and tolerances can be in the .005 to .010" range

Water jet will produce the best metalurgical edge, at the slowest speed and the highest cost....tolerances in the .004" to .010" range.

I have been in a few shops that have all three processes (plus oxy-fuel).....the processes all have their niche....and they should be used to produce the tolerances, productivity and cut part costs that are necessary for the application. There is no perfect solution!

Jim Colt

Everyone has their own preferences.

I looked at plasma then decided water jet had more versatility and delivered superior cut edges and parts; that's why I bought one.

Plasma might be a fantastic machine but water jets simply aren't as unproductive or expensive to run as some people make them out to be.

I can easily and quickly cut aluminium parts with better edge quality than the plasma parts in the photograph with the added benefit of no dross, heat spots or hardening.

If you want to cut aluminium in thin gauges quickly a water jet can do what you want competitively.... plus you get the built in capability to cut a mountain of other materials laser and plasma can't even touch.

Signmaker,

Sounds like your needs fit well with the abrasive water jet technology! As I was saying...each of the processes have their niche....for many...Plasma is the best choice when productivity and low operating cost are the primary need.

Water jet certainly has the versatility to cut a wide variety of materials with excellent quality.

It is always interesting to get metal parts quoted in quantity from two or three different processes.....you will see a pretty wide variation in tolerance capability as well as price. In simple terms.....if all parts quoted meet the tolerance requirements....then go with the process that provides the best price!

Jim