working with metal

[Custom carving]

has anyone had success working in metal, and if so what bits did you use. A friend of mine wants a coon dog themed mural. still looking for graphics also. haven't seen any treed coons in design and make


Dennis
some times you make memories
sometimes you make sawdust and firewood

[PRO4824]

Not sure how to share a thread but...
viewtopic.php?t=36045

[Rcnewcomb]

Here is a link to a project Beki did in aluminum: Aluminium Wall Art

[Custom carving]

thanks for the thread referral that was some awesome stuff they were doing but like one of the guys said BRASS IS HIGH!!!! i was thinking something like 10 gauge sheet steel

[Custom carving]

thanks RC i will have to check out becki's video too

[Leo]

Machining Brass alloy 360 is going to be about the easiest metal to machine, Bronze is a tin /copper alloy which has less machinability than brass which is a zinc/copper alloy. Aluminum is softer than brass, but gummy. Copper is softer yet but tears and is even more gummy.

SHARP cutters are needed - really sharp.

Problem with a CNC router is RPM and rigidity. Most low end hobby routers are not really rigid and RPM is too high.

Steel of any kind will be more than a challenge to near impossible especially sheet metal like 10 ga.

My recommendation will be to try Brass alloy 360. OR try some leaded brass,

[Custom carving]

My CNC has a water cooled spindle with an adjustable rpm setting now to find out how slow can you go? I will check into brass 360 thanks

[kstrauss]

I mostly agree with Leo except for his comment that aluminum is gummy. Yes, pure aluminum is gummy but common alloys such as 6061 and 7075 cut beautifully. A rigid machine, sharp cutters, spindle speeds that wood workers consider slow (typically 10000 rpm) and mist coolant together with an air blast to clear chips and ZrN coatings on your cutters to reduce chip welding gives excellent results..

[PRO4824]

I cut bronze and aluminum regularly but my son needed a 1/4" steel part at his welding shop so this is my only steel project and hopefully my last. Messy!

[martin54]

My CNC has a water cooled spindle with an adjustable rpm setting now to find out how slow can you go? I will check into brass 360 thanks

You probably won't get much below 6000 rpm & even if you could then you wouldn't have enough torque to actually cut anything
Metals like steel are generally better cut on a Mill rather than a router.

Just to add for anyone in the UK. brass standards are different to those in the US so for 360 free machining brass the standard you would be looking for is C121

[GEdward]

You probably won't get much below 6000 rpm & even if you could then you wouldn't have enough torque to actually cut anything

Very true. Although the frequency inverter is likely capable of taking the spindle down to single digit rpm, there is a very real danger of damaging both the inverter and the motor by going much below 6000 rpm for any extended period of time. As the frequency/rpm goes down, the amperage output of the drive goes up. I have taken my water cooled spindle down to 4500 rpm for short periods but the amperage indicated on the drive display showed 11 amps without any load on the spindle. The spindle motor is only rated at 8 amps. Water cooling gives you a little room for forgiveness but running under that condition for more than a few minutes is a recipe for disaster.

Ed

[TReischl]

I do not think you are going to have much luck cutting any kind of metal on a shark, the machines are just not rigid enough. Even shallow engraving is iffy on them. Don't get me wrong, not bad mouthing your machine, because my motto is "ANY cnc machine is better than NO cnc machine."

I cut aluminum on my machine, it is just "ok". A real milling machine does a much better job.

[sharkcutup]

I do not think you are going to have much luck cutting any kind of metal on a shark, the machines are just not rigid enough. Even shallow engraving is iffy on them. Don't get me wrong, not bad mouthing your machine, because my motto is "ANY cnc machine is better than NO cnc machine."

I cut aluminum on my machine, it is just "ok". A real milling machine does a much better job.

HEY I cut Aluminum with my SHARK CNC --- No Problem!!!

But HECK YEAH a REAL MILL would be better --- but show me someone who can afford one!!!

Sharkcutup

[Rcnewcomb]

but show me someone who can afford one!!!

In my part of the world you can find used Bridgeports for $2K-$3K on Craig's List. You would still have to convert it to CNC.

[rtibbs]

I

but show me someone who can afford one!!!
:
Sharkcutup

Mine happens to be a Bridgeport milling machine for metal work. You asked Shark......