Laser Cutting

[RWOLFEJR]

Hi,
Need some help figuring the best way to cut tiny Stainless tubing. I'm considering a "laser" (Dr. Evil... humor) but know nothing about them... at all.

Here's what I need to accomplish...
Cut 1/8" x .012 wall S.S. tube into 1/2" long pieces without a burr.
Minimum of 4,000 cuts a day... can be a couple shifts but quicker the better. (one part cut off every 14 seconds or less in one shift or a part every 28 seconds or less two shifts.) I've added some cushion to account for B.S. etc.

I have a picture in my head of how I will hold and rotate the part as it's cut but have no clue what I'd need in the way of a laser to produce a burr free cut and quickly. A secondary operation will be performed on the part after it's cut and I want to go straight from the cutting operation into the second operation. The piece that would drop will be held as it's cut and shifted into position for the second operation. From the second operation into a box...

Any other burr free cutting methods? I have concerns about water jet because my secondary operations won't appreciate dusty water getting in the mix. Co2 laser? Some other flavor? What's the best bang for the buck? How long does a "laser" last? What sort of maintenance do they require? Do they need a chiller or cool water supply to keep its entrails cool? What goes wrong with them? Who makes the best systems?

We aren't used to dealing with tiny things here but I hate to pass up the opportunity to quote anything that we might make a buck on and keep a guy busy. Any advice will be appreciated.

[parisp3]

Hi, will try to answer some of your questions:

1. First some background. Since your operation can be achieved by manipulating the work-piece, a stationary laser head will work. Some industrial laser types such a Nd:YAG or Diode work quite well with robotics because they can be delivered via fiber-optics. the CO2 is less flexible from a deliverability stand point but in your case shouldn't be an issue.

2. The Co2 and Nd:Yag have a longish history of being used for cutting, the primary difference being the CO2 generates a continuous wave while the YAG is pulsed. At low pulse rates and high speeds a rough edge can be formed with the YAG but with the right combination of speed and pulse rate, an acceptable edge is achievable. Talk to the OEM and they will be able to guide you, there is tons of literature available. One benefit of the YAG over the CO2 is that its wave length lends itself better to being absorbed by a shiny metal like SS or Al.

3. Both laser types can easily generate the energy required for your cutting operation, however when I worked with lasers about 10 years ago the Co2 was easily the most efficient laser on the market about 10% energy conversion efficiency as opposed to about 1% for the YAG all other things being equal. That's something to keep in mind while talking to your OEM.

4. Since the energy conversion efficiency for lasers are low, they usually come with chillers (waste heat). The part itself does not need cooling per se...the spot sizes at about 10 microns and the focused beam leaves a minimal heat signature. You can shroud the operation with an inert gas like Nitrogen or Argon if you like if you do not want the edge to oxidize, for many commercial applications there generally isn't a need. With the Co2 laser there is a gas mixture which achieves the 'lasing' if you will, so CO2 gas would be a consumable and will need to be replaced, although I have heard there are sealed CO2 lasers available that don't have this requirement.

5. Finally, there are big name OEMs like Rofin/ Coherent or Trumpf. Others like Kern or Vytek are worth a look. I worked with a couple of small OEMs and had a pretty good experience, will pass the names on when my memory comes back a bit.

[Kelly_Bramble]

What parisp3 said....

I think laser cutting is your solution. "1/8" x .012 wall S.S. tube into 1/2" long pieces without a burr." that's easy...

See this demo video ---> CNC Laser Cutting Tube

[jackieann000]

Agree with the above thread. You can get more stuff about laser cutting from the internet.

[local]

Hi there. The thread is very old but will try to provide all the answers.
1. For big production tube cutting only fiber lasers are used today. All other technologies (for example CO2 with mirrors) or waterjet (should be unique) probably could be but not as in the mass market.
The achievement is also speed, speed and speed. Machines are complicated and expensive so you need to consider really big production to invest.
2. If the parts are just profiles to make holes (for example metal rack production) in this field also tube punching machines are used. But it is not the freedom of laser so only holes and only with geometry of tools you have in the machine.
3. Laser normally will be near burr free, mostly because the wall thickness is not so big. So in general there is no other equipment to proceed parts after cutting.