CNC Laser cutter versus CNC Plasma cutter?

[squale]

what are the advantages/disadvantages of a cnc laser versus cnc plasma machine?

and which one is more expensive?

can you put a router head on a cnc laser machine?

[zhangrui1588]

Originally Posted by squale what are the advantages/disadvantages of a cnc laser versus cnc plasma machine? and which one is more expensive? can you put a router head on a cnc laser machine?

cnc plasma machine is more expensive

[jpgdesigns]

I would have to disagree with zhangrui1588...
first, you need to decide what materials and what thickness you would be cutting.
then, decide on the cut quality you are looking for.
With those two decisions made, call several laser and plasma machine manufactures... tell them what material and thickness you plan to cut and at what quality you expect.
You will find that the laser guys will be more expensive.
Just an example... 400 watt laser - cuts paper, cardboard, thin wood, acrylic & metal to 1/4" per Synrad power calculator. The thicker the material the more watts you need, the more speed the more watts you need. More watts=more$$$,$$$.$$

While plasma can only cut ferrous and non-ferrous metals. $50 to 70 thousand will get you laser quality cuts up around 1" thick

The optics and alignment of those optics don't like vibration... I would not put a router on a precision laser machine.
Just my 2cents.

[JerryFlyGuy]

zhang is dead wrong on this one. On a apples to apple comparison the Laser will make the price of a plasma seem like your stealing it.

The differences are in the quality of cut and thickness & type of material.

Lasers are fastest w/ gauge material up to ~1/4" from 1/4" to 1/2" they are getting close to par w/ plasma's as far as cost per inch and speed. After 1/2" plasma will start to pull ahead of laser in speed and cost but will lag in quality.

The majority of main stream lasers will cut up to 7/8" easily and are 'rated' up to 1". Plasma will cut well in excess of 1" [up to 3" w/ the Hp260 power supplies]. If your wanting to go past this your limited to Waterjet [slow but very precise] or Oxy fuel torch which will be faster but w/ less precision.

Also it's worth noting that the quality cut of a plasma is entirely dependant on the type. The new genertion High Definition Plasmas [Hypertherm Hp260 for example] will generate nearly as good a quality as a laser. The down side is you have to replace your tips to maintain this quality as you move up and down in material thickness. I've never done it or seen it done, but it's supposed to be a pretty simple, straight forward process which takes only a minute or so. Lasers have optic's which automatically adjust for the various focal lengths needed for varing material thicknesses. Lasers are also more difficult to maintain. Usually you'll have to get a tech in from the manufacture to adjust the focusing mechanisim's and polish the mirrors etc. Plasma's, waterjets and oxy fuel torches are all shop maintainable [for the most part anyway].

We've just purchased a machine which will do plasma AND waterjet on the same setup [same machine/gantry] and feel we're getting the best of both worlds in our ability to cut fast and/or accuratly, at will. Time will tell as it arrives in about 2-3 weeks.

Fwiw...

J

[dcorbett]

Jerry, you are dead right on that one. We have both, and the plasma was less than ~1/10th what the laser cost. Hardly "much more expensive".

By the way, you are going to LOVE your waterjet!

[JerryFlyGuy]

Hope so.. we did a huge job last year w/ 99% stainless and used the WJ [contracted] to cut holes which we then just ran a tapping head thru.. and voila... worked amazinly well.

The beauty of a combo machine is the ability to cut the parts that aren't critical w/ plasma and then immediatly switch over to water and cut the high tolerance edges.. [or Vs Vs] so setup's nothing.. all in the same process.. It should be a winner..

J

[claser]

You can't compare plasma and laser so easely in general, so I agree with them who disagree with zhangrui. Plasma is usually used for bigger, less detailed jobs and this can be cheaper but when quality is required - plasma can't compete with laser. You just can't reach it with plasma, or further machining, polishings will cost you more than work based stright on lasers.

[jimcolt]

Not quite true. High Definition class plasma competes very well with laser on a variety of materials.....as the materiel gets thicker....the plasma competes better. Typically on material thicker than 3/16"....plasma cuts faster.

A 5 x10 cnc plasma machine with plasma capable of cutting to 1-1/4" can be purchased for around $100,000. A laser with the same capability would typically be in the $550,000 range.

Cost per foot of cut with the plasma is about 1/4 that of the laser, the laser can hold tighter tlerances...although on thicker materials the tolerances are close.

If you have the need to cut 1" steel at 85 inches per minute....plasma will do it with very nice quality. Attached is a picture of gauge through 2 inch steel all cut with a Hypertherm HD400xd high definition plasma.

Jim

[claser]

Thanks for the photo - first two elements are quite convincing (quality). I had to do with much worse products from plasma machines - so, I'm partyl convincing.

[jimcolt]

A lot of people have in their minds the plasma quality from machines that were designed 15 or 20 years or more ago! The technology has dramatically changed in the last 10 to 15 years.

Lasers, water jets, oxy-fuel and plasma all have their best market niche's.....but plasma has gained a lot of ground in terms of cut quality, cut thickness, consumable life, speed and operating cost. The cost of cutting with plasma (with the right equipment) is a fraction of what it was 15 years ago as well.

Jim

[cowleym]

We have had good results cutting aluminium with the thermal dynamics ultra-cut plasma using water as a shield.

Mike