Homebrew Laser Cutter Made by Zach Radding

Zach Radding and his daughter Taylor built some robots with his own CNC laser cutting machine.
Take a look at more projects and information on the courses he teaches.
So far, he has made two laser cutting machines.
Click on the small numbered picture above to learn more about them.
Note: None of these are fully detailed plans.
Includes the part number of all major components.
This information will help you adapt to laser cutting if you have already made some type of CNC machine.
You should build a CNC router table before trying the laser cutter.
The book \"CNC robots\" by Tab books has a good plan. www. nutsvolts.
Com is used to send you a plan for two cnc machines subscribed.
Zach recommends homemade cnc information.
He likes the Dancam cnc software.
There are some warnings first.
The laser is invisible.
It can blind you and your loved ones in an instant.
Here are the safety glasses Synrad provides for the use of this laser tube.
Read all the manuals that come with the laser tube and do what they say.
If the laser shines on the wrong material, it can cause a fire and produce toxic gas.
The first version uses the Roland Digital pen drawing machine to move the cutting lens and contains many laser cutting mechanical parts.
The following components are used by Zach.
The price has changed (fallen)
He bought his from 94 years and some of them were no longer made.
Similar components are available, or you can look for them in the secondary market.
Here are the components he uses: CO2 laser tubes: Synrad G48-2-
The laser Cost of 285 25 W is about $2000 for power supply: SPM3E2K 28 V 27 amp switching power supply.
Mirror for about $300: four high quality front surface mirrors for $20 per mirror.
Focus Lens: it must be made specifically for laser wavelength.
For the light of this color, it must be optical transparent, it will etching and melting.
Zach\'s Lens received a 45 degree front surface mirror from Synrad for $600, and Zach and Taylor showed us the second version of the laser cutting machine.
The first version works fine, but some movers use it as a box for transporting a crazy coyote that they think is his pet.
The poor animal completely broke the machine before it came out and bit Dick Cheney in the woods near D. C.
By that time, Zach had gotten a heavy x-
I think he will try different designs.
This version moves the workpiece instead of the laser beam.
The main advantage of this scheme is a very simple optical system.
The optical system consists of a mirror that points the laser beam below by focusing the lens.
If Zach made another machine, he said he would make it more like the first one.
Let\'s take a look at this courage first.
SPM3E2K 28 V 27 amp switching power supply.
Costapprox $300 this is a normal switching power supply with no special ability and good management.
The laser tube requires a voltage of 30 volts plus or minus 2 volts and 30 amps.
Any supply to do so is good.
CO2 laser tubes can be seen from above.
It\'s Synrad G48-2-
The 285-25-watt laser cost about $2000 of the fan in the blue case (
Absent in this photo)
Blow the air into the hole of this transparent shell around the laser.
This can cool the laser and prevent smoke and other dirt from entering the front of the laser.
This is a good way to prevent the laser itself from burning a hole.
There are a lot of good features in this unit.
It requires a relatively low 30 V power supply.
It has an internal voltage of up to millions of volts.
This is how many Volts the laser does not need. lazy.
The device also has a convenient DB9 connector with TTL level (five volt)
The input signal line used to turn the laser beam on and off.
PWM can be connected (
Pulse width modulation)
Signal here to lower the laser power to whatever level you want.
The PWM frequency of Zach is 20 khz.
\"The new laser uses an old one,\" says Zach.
600 motion control card.
With XY table.
I found a utility (from Galil)
It converts the HPGL file into a format that its motor controller can recognize.
I wrote a VB app that allows me to preview the cut and send the motion control file to the Galil card.
I would love to share this but I really don\'t think it will help anyone.
\"This small pic f675 microprocessor board runs the control panel and regulates the pulse width of the beam (
PWM changes the apparent laser power, thus changing the cutting depth).
The processor looks at the stepping and direction signals of the stepping motor controller.
The speed of the workpiece movement is derived from this, and the laser power is adjusted to match.
Sports are faster and more motivated.
Circles and other curves cause the machine to move slowly as it approaches a circle from a series of tiny line segments.
Then, the laser power needs to be lowered to match the slow speed.
When etching an image onto something, it\'s more important than cutting something.
This is the whole optical system.
In this photo, Zach\'s finger is screwing a screw that focuses the lens up and down.
This is necessary for materials of different thickness.
This applies the hottest part of the beam to the surface of the workpiece.
Commercial machines often enhance and reduce the platform to support the workpiece.
Black triangle dinggs contains a front
Mirror at 45 degrees angle.
The thumb screw pushes the mirror around so that the laser beam is aimed in the right direction, which goes straight down by focusing the lens.
The focus lens is a whole piece of glass displayed in the lead screw mechanism of the aluminum block for two months --40 capscrews.
The lens housing is a unit that comes with a 45-degree mirror for about $600.
The mirror was in the wrong place for this machine, so Zach cut it off.
Here are some nylon lines.
They usually take smoke hoses from the lens.
This is important.
Smoke without airflow can prevent good cutting.
In addition, it will burn on the optical system, which is a tragedy in addition to those who sell expensive lenses.
The hose that sucks smoke from the lens used to go to the blower, which blows smoke out of the building through the vent.
The smoke from cutting the plexiglass is so bad that the smell that floats back from the outside is unpleasant.
Let Zach buy the unit.
It blows away ordinary smoke through a charcoal filter, which absorbs all the freshness. It\'s a RSU12-
The \"space\" model of human rights consultation was conducted by Electrocorp.
He said it was better than the air quality that the exhaust fan gave him.
I asked Zach if it is possible for the laser cutter to fix the workpiece vertically in order to save the floor space, does he think convection will cause fire.
He said no, every laser cutter has to have a lot of air flow through the cutting so the problem doesn\'t make any difference.
In his view, the biggest problem with the vertical workpiece is that the cutting part will fall off, shift, collapse, and may fall into the cutting and stick itself together.
Back to version one.
Zach ordered a new digital stroke machine from Roland for about $800.
It understands the HPGL and its own drawing machine driver protocol.
In order to cut the part, Zach drew the line and clicked the \"drawing\" button in his cad program.
The draftsman started working, not sure that Zach had connected his laser and mirror as shown in this chart.
This is the most common configuration for commercial laser cutting machines.
Zach has no problem with the mirror and if he makes another laser cutter he will use this arrangement again.
For different line styles, the draftsman has a pen-changing function.
Zach added a button at the Pen change station to tell his laser controller what kind of cutting is expected.
The controller then sends a PWM signal to the laser to control the brightness of the laser. The pen-up and pen-
The down signal from the drawing machine is used to turn the laser on and off.
As can be seen from the picture above, this picture depicts the machine.
Mirror 4 points the beam directly to the workpiece through a focused lens.
Mirrors 1 and 2 are fixed.
Mirror 3 attached (blue)x-
Shaft gantry and moving sideto-side with it.
Mirror 4 and focus lens slide-and-
Back and forth on the gantry.
This is the mechanical part of Zach\'s first laser cutting machine. The x-
The shaft stepping motor rotates a long axis with two pulleys.
Two timing belts move the gantry back and forth.
A smaller steper motor on the gantry moves the pen holder-and-
Back and forth on the gantry.
Zach replaced the pen holder with a mirror #4 and a holder for the focused lens.
Over time, Zach replaced the frame elements with aluminum profiles and various brackets with laser cut lucite parts.
The stepping motor is connected to the drive through a flexible coupling.
There is a timing pulley at each end of the transmission.
The two belts are connected at both ends of the gantry.
Pulling both ends of the gantry prevents the shelf, meaning it doesn\'t have to be as stiff as it used to besupported.
Gantry seen from below.
The carriage has three wheels on the track of the gantry.
The bracket is attached to the timing belt driven by the stepping motor on the left side.
Another view of the gantry.
Please note that on the lasercut plexiglass stand.
The lasercut plexiglass Bucket replaces the original pen holder.
It supports mirror #4 and focus lens.