[HH] limitations of laser cutting

[Greg London]

I'd gut check laser ablation to be slow but extremely high res.
good for very small, very detail demanding parts,
but not so much for home enthusiasts.

As for cutting, the plasma training I took placed cutting in this order:
laser, plasma, water jet. (from thinnest material to thickest)

As for metal machining, I think these machines have pretty
low precision. You could probably make gears that work at low speeds,
but but I can't imagine making anything high precision or heavy duty.

A manual bridgeport is 2000 pounds of iron to keep the table, bed, head
from flexing and vibrating while cutting.  I haven't looked for  a
cheap new/modern CNC mill, but some quick window shopping usually had
them be in the tens of thousands of dollars range.

I imagine a desktop "mill/3d printer" would have a precision that
would be on the order of "better than casting".

So, even when discussing the "same" category such as "traditional milling",
there are wild variations of quality and price.



On Sun, April 12, 2015 4:21 pm, Bill Bogstad wrote:
> On Sun, Apr 12, 2015 at 8:18 PM, Tom Metro <tmetro+hhacking at gmail.com>
> wrote:
>
>> Bill Bogstad wrote:
>>
>>> What are the pros and cons of  traditional milling (cutting edges
>>> requiring physical contact) versus laser micro-milling (i.e. laser
>>> ablation with a pulsed laser)?
>>
>> My understanding is that the reason why you hear the term "laser
>> engraving" far more often than "laser cutting" is that lasers powerful
>> enough to cut are still really expensive. The machine in this thread I
>> think maxes out at cutting thin balsa wood.
>>
>> In contrast, the milling head can handle wood, aluminum, brass, and if
>> you go slow enough, some steel.
>>
>> Laser cutting tends to burn the edges and leave a rougher cut than some
>>  other processes.
>
> From the wikipedia article on laser ablation:
>
>
> https://en.wikipedia.org/wiki/Laser_ablation
>
>
> "Very short laser pulses remove material so quickly that the
> surrounding material absorbs very little heat, so laser drilling can be
> done on delicate or heat-sensitive materials, including tooth enamel
> (laser dentistry):"
>
>
> Now it may be that lasers with this intensity are too expensive.
> Still if it is being used for dentistry,
> they can't be that expensive.   According to
>
> http://en.wikipedia.org/wiki/Dental_laser
>
>
> "Use of the dental laser remains limited, with cost and effectiveness
> being the primary barriers. The cost of a dental laser ranges from $4,000
> to $50,000, where a pneumatic dental drill costs between $200 and $500.
> The lasers are also incapable of performing some routine
> dental operations"
>
> $4,000 isn't cheap, but not out of reach either.   Perhaps people just
> haven't tried it yet.   Or it takes too long to remove appreciable
> material.
>
> Bill Bogstad
> _______________________________________________
> Hardwarehacking mailing list
> Hardwarehacking at blu.org
> http://lists.blu.org/mailman/listinfo/hardwarehacking
>
>


--