Well, if you are spending or financing against your own pocket, you can save 10's of thousands of dollars setting up your own system. Suppose you have a few thousand tied up in a running yag laser, between $1000-4000 on an xy table system. Then you need some method to get the beam from the laser to the part. If you opted to have a system that employed a moving table, you can mount the laser to the z axis. If you want a gantry system, you can use a fiber optic cable to carry the beam. Both options require a lens at the end to focus the beam down just like the "Gucci" of the shelf markers have.
Here is the trade off as I understand it: Marker vs. XY
$30k off the shelf laser marking system
Advantages:
A) Easy set-up
B) Compact size
C) Low power requirements (I think you can power some of them on 110v)
D) Short cycle time
Disadvantages:
C) High initial capital investment
D) Most replacement parts are proprietary to the manufacturer(if it breaks down, bend over, or scrap your unit that just cost you a small fortune)
E) Individual parts must be loaded in front of the system one by one because of the small work package. labor cost's are higher because the unit must be manned during operation. You could add a pick and place, but that is another subsystem to fail, and another control routine to worry about
F) Most laser companies discontinue support after a few years, and parts dry up, rendering them useless.
G) The depreciation is worse then buying a new car
Gantry or Milling machine style XY
Advantages:
H) Very low capital investment start up cost in comparison
I) Laser acts as an external entity to the XY system. If it blows up, you can roll up a spare, and be back online for 10's of thousands less(even if you had 2 units)
J) Only the control components on board the laser are proprietary. That is if you opt to use the turn key laser systems. If you select the proper unit's, the parts are dirt cheap
K) The cost per watt is substantially less. I have never dealt in my own collection with anything less than 90w of YAG output. Of course you can use it at 1w. The benefit to over sizing is that the consumable the flashlamps life exponentially lengthens the lower you run the power.
Example:100w max power output laser
Operated at 100w all the time: Flashlamp may last 700-1000hrs
Same laser at 20w all the time: Flaslamp life in the 10's of thousands of hours
(worst case you buy the $29.95 lamps on Ebay new when they are listed for your system)
H) Your working package can be as large as you decide. I would propose to make gang tooling(a plate of material with slide fit tolerance to put the tags in) so you can load all 25 pcs at once. Then hit go, and go drink beer! Then unload at your leisure.
G) motion components are generic
H) Control software is not proprietary. I would propose to use step and direction style servo drives. I buy yaskawa myself. I currently have over 50 motors for my projects. Highest reliability of any servo's system's made. Readily available on Ebay. Since the big 3 automakers only use allen bradley , the price is not artificially inflated due to the smaller equipment suppliers that have to use them and often buy them off Ebay. Yaskawa's support is awsome (even if you got them 2nd hand). All documentation is readily available on there website, unlike most of the servo clowns. if the system is older than a few years, they want nothing to do with it.
L) Even with the smallest unit's that make paractical sense, you can cut material if you choose. That open's up a whole other potential for making money. The precision is in the xy, no real worries about the system rigidity to acheive accuracy to some degree. You main precision enemy is only vibration, but no opposing tool forces.
Disadvantages:
M) Larger system footprint
N) More thought has to go into optimizing feed rates, and inertia matching
O) longer time to market initially
P) More costly/time consuming to integrate safety guarding since the work package is larger potentially
Q) Requires more design time (time=money)
I am sure I missed a few pro's and con's. Just my experience. I hope this helps  |