Buildlog Title: Laser Build (Based on 2.x)
Builder: karsten
Member Since: 2015-08-13
Friday, June 17th 2016 - 4:53 AM
good day members of this forum!
I almost finished the machine, but i have a problem with one of the Motors/Drivers
I am using this for the Y axis
Motor:.9deg Nema 17 Unipolar 12V 0.4A 32Ncm Double Shaft 17HM19-0406D
Info(
http://www.omc-stepperonline.com/9deg-n ... p-121.html)
Driver: Bipolar Stepper Motor Driver Max 3A Current 128 High Subdivision ST-7128
Info(
http://www.omc-stepperonline.com/bipola ... p-244.html)
Its connected as bipolar ignoring the 2 cables as is described in the diagram, the motor works but it does a bit of noise, more than enough for notice, i think the problem is the current, but im not sure, can you tell me? and if its possible recommend a replacement how works fine?
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Wednesday, September 9th 2015 - 9:31 PM
You are right
cvoinescu its the Y axis, sorry
I started purchasing some pieces, waiting to arrive
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Monday, August 31st 2015 - 9:28 PM
thank you cvoinescu, sshwarts for your answers
Questions!
-- The stepper motors are ok? one is unipolar the one for Z axis with double shaft
-- The belt for Z axis is continuos in the design of the 2.x, modifying the size of the machine affects the lenght, where i can buy it, or what options i have
-- Searching Laser heads in ebay, some of them give this options:
Mirror diameter
Lens Diameter
Focal Lenght
I dont really understand the laser optics calculator of this forum :/ my only guess is it depends of the tube and size of the machine ??
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Monday, August 24th 2015 - 9:46 PM
thats a lot of water!! xD
the laser tube generates that much hot? i planned to put a 360mm Radiator with a Push-Pull configuration to cool it
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Monday, August 24th 2015 - 6:01 AM
thank you for the answers!!
rsm5178 wrote:With a higher wattage power supply, you just can't use full power. There is a current limit of the laser tube. I run a 60w power supply for my 40w laser tube. I can only use 38% of the power supply since my tube'S maximum current is 18.5mA.
I know there are people who cut 6mm mdf with a 40w tube. May need 2 passes.
A bigger machine would be much easier to stuff a 60w tube into though....
Rich
So, its the same as it is with a PSU for a Computer, i cant put any PSU for the laser, lets say, 100W for example, and use it with a 40W tube without problems, the PSU just deliver the power needed for the tube
Another Question, i want to use a custom water cooling system from a Computer for the laser tube, but im not sure about the tubing, the laser tube its made from glass, how strong is the tube or how you connect the tubings at it :/
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Monday, August 17th 2015 - 11:01 PM
Hi!!
This is my first post, and first of all.... english isnt my native language
so, if i begin to talk like Yoda please understand me haha
Im 24 years old, studying Industrial Design, and well, as the title says, that is my intention. Do a home build CO2 Laser for cutting and engraving. Its in the school where i start using laser cutters (i didnt operate the machine, just arrived with my files to cut
)
This are two of the projects i made with Laser.
And... as a fan of Star Wars....
Arrived to this forum a few months ago, looking for information about how to build a machine of this type, now i think i understand enough to start... buying at least hahaha
Dimensions of the machine... i would like at least 60x45cm of cutting area (same as the machine in school) still planing...
This is my Buy List until now, incomplete but i have a few questions
Switching Power Supply 400W 24V 16.7A for CNC Router Kits 115V/230V S-400-24
http://www.omc-stepperonline.com/switching-power-supply-400w-24v-167a-for-cnc-router-kits-115v230v-s40024-p-240.html0.9deg Nema 17 Bipolar Stepper Motor 2A 46Ncm 17HM19-2004S
http://www.omc-stepperonline.com/09deg-nema-17-bipolar-stepper-motor-2a-46ncm-17hm192004s-p-122.html0.9deg Nema 17 Unipolar 12V 0.4A 32Ncm Double Shaft 17HM19-0406D
(Question: affects too much that this motor is Unipolar? its for Z axis, the table)http://www.omc-stepperonline.com/9deg-nema-17-unipolar-12v-04a-32ncm-double-shaft-17hm190406d-p-121.html50-60W CO2 Laser Power Supply for CO2 Laser Tube Engraver Machine Professional
(Question: it would work for 40W Laser Tube? How much Power i need to cut MDF 6mm thick for example)http://www.ebay.com/itm/50-60W-CO2-Laser-Power-Supply-for-CO2-Laser-Tube-Engraver-Machine-Professional-/221545310032Set Co2 Laser Head +Mirror + Lens Intgrative Mount Cutter Engraver FL 1.5" to 4"
(Question: From China, Is it good? )http://www.ebay.com/itm/Set-Co2-Laser-Head-Mirror-Lens-Intgrative-Mount-Cutter-Engraver-FL-1-5-to-4-/331329488393?pt=LH_DefaultDomain_0&var=&hash=item4d24c6c609AWC608 Commercial DSP CO2 Laser Engraving/ Cutter Controller
http://www.lightobject.com/AWC608-Commercial-DSP-CO2-Laser-Engraving-Cutter-Controller-P321.aspxAbout the drivers... I am looking to this two, is much difference?
Bipolar Stepper Motor Driver Max 3A Current 128 High Subdivision ST-7128
http://www.omc-stepperonline.com/bipolar-stepper-motor-driver-max-3a-current-128-high-subdivision-st7128-p-244.htmlLeadshine DM422C Digital Stepper Driver 20-40VDC with 0.3-2.2A
http://www.omc-stepperonline.com/leadshine-dm422c-digital-stepper-driver-2040vdc-with-0322a-p-75.htmlIts all i got for now, i will prepare my next questions hehe, thank you so much forum
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While that is partly true, mother nature isn't quite that helpful here. If optics would follow geometry perfectly, you'd be exactly right. However, diffraction makes the spot wider and fuzzier than pure geometry would have it. Instead of a double cone, the beam never focuses to a point. Instead, it just goes thin then wide again, like the pinched part of a hourglass -- only fuzzy on top of that too. The carbon dioxide laser has a very long wavelength, so the effect is a significant limitation. For the same diameter lens, a short focal length would have a higher numeric aperture and hence less diffraction, so the beam would get fairly close to a point in the focal plane. A long focal length would have a large depth of field, yes, but its smaller numeric aperture would cause the beam to be much more dispersed even at the exact focal plane. For cutting thin materials and engraving flat objects, then, a short focal length is much better.
The beam width makes a difference, though. For the same focal length, a wider beam focuses closer to a point (higher numeric aperture, lower diffraction), but has a shallower depth of field (wider cones). Unfortunately, the beam width is set by the construction of the laser tube. (Beam expanders exist, but I don't know whether they improve diffraction the same way as a laser with that native beam width; they do make the depth of field shallower, as you would expect.)
Typical focal lengths for small lasers are 25 mm (for fast, precision cuts with small kerf in flat, thin media), 100 mm (for slow, wide kerf cuts in thick materials), and 50 mm (a reasonable all-round compromise, and the best choice for medium-thickness materials).