How to purchase a CNC laser machine?

[ifin]

can anyone with experience in purchasing a laser give me some pointers on,

-machine selection
-justification

or any other documentation involved as far as research and recommending a machine?.

Thanks.

 

[revdode]

Both machine selection and justification tend to depend on your business and local factors. For machines in the UK I would tend to stick with Trumpf, Bystronic, and LVD although this may not be relavant in your area. There are other good machines on the market but investigate the service and support they currently give to their existing customers in your area.
What kind of business are you trying to justify the machine for?
Generally flexibility, saving in change over, saving in tooling costs and the ability to easily mix multi-part nests are the best arguments. Part cost especially if you are cutting with shop air is another track, your prospective suppliers should be able to get you part cycle times and help build a costing model to allow comparison with existing costs, if they won't one of their competitors will. There are downsides to a laser, pressed forms have to be carried out off the machine, secondary ops or a CNC punch for these parts. If you rely heavily on staked assemblies, self locating features, or plunged holes then it's harder to justify.
I've been involved in justifying a machine in a low volume job shop and it all came down to flexibility although that comes at a cost. Don't forget the time/trouble of generating dynamic nests if you go for improved material utilization. In a high volume situation we justified a machine by reducing lot sizes and the amount of material on the floor, the piece part price was neutral.
Start with the business you have and look at what you are trying to do, that is often the easiest although sometimes not the most convincing justification.

 

[ifin]

Thanks Revdode,
if you had to layout a simple sequence of events what would it look like?
would you start with justification, costing
OR
machine research?.

I already have access prints and costs of the parts that we would like to primarily do.

 

[tripleZ]

Most machines I've justified have looked at a combination of the work and the machine's costs/capabilities as a starting point. It sounds like you've identified where your problem is, or where you perceive your problem to be. Start by answering the question "How will a laser cutter help my problem". List out your solutions, then try and place a cost to each item. You can generally ballpark it to start. Then look at machine selection and the associated costs. If you've never done this, research a manufacturer's website to find out what you think you need, then call a sales rep. Have your ducks in order regarding what you want the machine to do, acceptable rates, materials, etc. Get a rough estimate. Then compare the two. Your results should tell you what course of action to take next.

 

[kagan]

You should consider
- The material type that will be marked. Because Laser source will be defined with that information. CO2 or diode type for example.
- The marking surface: ND YAG type lasers gives you a white marks on phosphated steel surface, but also black marks on machined surface. If you will mark a code system such as datamatrix or barcode, you should have good surface.
- The quantity: an area of 20mmx20mm takes about 6 seconds according to your contrast requirements on the surface. An average diod life guarantee is app 7500 hours. But it doesn't mean that you can mark 7500x3600/6. Because when you open the device, you use the life even you don't mark. So spare part price is also important.
- The diode type: Mostly you can find ND YAG diode type lasers. I heard that there is also new generation lasers which has a tecnology of fiber type with 100.000 hours life guarantee.
- Power : The new generation lasers use app 5-10 kw. But olds are 50-80 kw. So less power means less device heat and air coolant, more power means water coolant and piping.
-Smoke: Every laser produce smoke during marking. So may be you will have to use a smoke collector.
-Z axis: Some brands have manual Z axis for focusing some brans have automatic with servo motor.
-Q switch: The automatic adjustgement of power consumption. This is also a key.
-Service and maintenance: You can find some cheap brnads from Thaiwan or China, but consider that they will send you the spare parts or etc. from the same distance if they don't have a strong representative.

You can also find some additional information in

http://www.technifor.com/uk/index.htm

 

[AndrewUK]

what are you wanting for ? new work process improvements?
Are you buying one and need to know what to look for or you writing a procurement spec. ?

Bought and used a few lasers.

 

[ifin]

My boss wants me to pick out a laser.

This would be my first capital equipment purchase project, I think he has put me in charge of this more for as a test.

what are steps you would go through while purchasing a capital equipment
-payback
-operating cost
.
.
.
?

 

[AndrewUK]

Again why are you buying a laser? Capacity? Technical advantage? Replacement?

Cost Price
Installation Price
License costs for software ( one off costs? Yearly support?)
License for CAD/CAM package to write programs.
Warranty and spares
Maintenance contracts support (call out fees, time, cost)
Facilities required (power usage, networking, extraction, air)
Foot print of machine can you fit it where you want? Can you get it in through the doors or will you have to take down a wall?
Weight of machine? How will you lift it off the truck when it comes?
Training
Proof of performance (don’t rely on brochures send samples off to all possible machine companies and ask them to provide you with machine samples of your product)
Visit (go to another factor and see a machine in action, ask for details of people using their machine and compare quoted performance with actual)
Payback period
Compatibility with existing machines (i.e. can you output the same program from CAD/CAM to existing machines and the new one? If they say you can get them to prove it.)
Firm date they can deliver (some machines have huge waiting times)
Depreciation costs.


some general points i'd ask for any machine and get it in writting if you call anyone copy it in an email after.

What tyoe of laser you after and what to do ?

 

[ifin]

-80% work would be 12 Gage cold rolled steel/stainless steel/brass ( decorative doors - leaf patterns, arch ...)

-some rapid prototyping

- porting ( .106 Round holes on tubes )

- anything else around the plant that would make sense to be a laser job that would justify purchasing this machine.
(nothing we do is more than 1/4" )

 

[ifin]

Main objective of the first in house laser:

-save cost on the purchased laser cut decorative doors (leaf patterns , arch)

- too many different patterns, sizes making it difficult to handle logistics with the vendor

- long lead times.

 

[CompositeGeek]

Yo Ifn,

I suggest you make a short list of equipment manufacturuers. Prepare a few blank examples of the problem you are addressing - be prepared; give them materials, parts etc, that are the same as what you will use the equipment for. Then send them to your top 5 candidate vendors and ask for a FREE demo of their ability to solve your problem. They should be able to do this for you if they want to PROVE their systems will solve your problem so they can close a sale.

You will still have to do heavy lifting on the financial justification and planning side. But if this is your first capital equipment buy, I strongly suggest you make the vendor sell and justify to you and I also suggest you use each vendor as a yardstick against the others.

I have bought multiple units (Various machine types, including CMM, CNC, Laser punch, etc) using this strategy.

Oh, and plan on this activity taking a while. If you need the equipment in the next 6 weeks you may have a problem with this approach.

Good Luck!

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