Sunday, June 20th 2010 - 5:40 PM
I’ve been distracted lately with the broken Harbor Freight 7" x 10" Precision Mini Lathe I bought off eBay for $150. Shipping cost $115 which wouldn’t be such a big deal lf UPS didn’t further damage the lathe.
When the lathe arrived the power rocker switch would light up but the system was unresponsive; thanks to UPS, it also arrived with a broken cross slide lead screw, dented cross slide dial, broken cross slide crank handle, and shattered change gears cover. Once I get the lathe cleaned up and repaired I’m going to install a 2 axis DRO, a quick change tool post, and a custom spindle tachometer.
I haven’t stopped working on the laser system. I finally got the laser tube mounted in the frame followed by the water cooling setup. Since I still have to use the laser to cut the panels for the frame, this setup is only temporary. I didn’t want to waste actual liquid coolant so I just used Copper (II) Sulfate Pentahydrate mixed with distilled water; I usually mix them at approximately .6ppm of CuSO4•5H2O per liter of distilled water. I'd like to see anything try to grow in that water!
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Sunday, June 20th 2010 - 5:35 PM
lasersafe1 wrote:You need to activate the limit switches in the DSP control software under machine settings. You also need to tell it whether it is high on limit or high off limit.
I just assumed that since it homes to the machines zero that the limit switches were functioning to their full capabilities. I have yet to connect the DSP controller to the computer and get that setup.
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Monday, May 31st 2010 - 6:08 PM
The air assist nozzle started out as part of a pneumatics air regulator; I modified it on my ghetto lathe (drill press and a file), then finished it with some 1000grit sandpaper and a pass through the buffer.
It’s attached to the lens mount with the rubber grip from a tripod. I will eventually replace it with one machined from stock aluminum like yours or I’ll print one on my 3d printer once I finish the heated bed.
The 3d printed air assist nozzle is the more likely of the two options as the print quality was good before I started making upgrades and the heated bed will only increase the quality; it’s just a matter of time.
I had planned to test the laser tube and laser PSU today until I read a post on lightobjects forum saying the wiring diagram that I was given isn’t correct for the DSP board I received. I’m not the type of person to just plug it in and hope it works, especially when it comes to lasers. So for now I’m stuck waiting for a reply from Marco.
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Monday, May 31st 2010 - 4:42 AM
A mascot, is that what my build log has been missing?
I got the motors for the X and Y axis wired up along with their respective limit switches. The DSP controller drives the motors just fine and the limit switch indicators on the board light up when the switches are hit. There’s just one problem, the motors don’t stop when the limit switches are hit.
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Wednesday, May 26th 2010 - 12:20 AM
The ICs came in from Maxim… I knew that QSOP packages were small but when I can fit six ICs on my fingernail it comes into perspective. Soldering these ICs should be interesting …
I was proofing a paper my younger brother wrote on lasers and one particular calculation he made is very interesting. He used my 30 Watt laser as an example and calculated that while lasing at 30 Watts, its emitting 1.60x10^20 (160000000000000000000) photons per second . This of course means that the energy of each photon is 1.88x10^-20, quite incredible really. It begs the question that if we could calculate the strength of material in the number of photons it takes to cut through it, we would then be able to calculate the optimal speeds for any given material.
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Thursday, May 6th 2010 - 6:56 PM
It’s been awhile since my last update but that does mean I haven’t been busy working!
Frame: Assembled and squared
Mechanics: Assembled, waiting to be aligned and tightened
Core Electronics:DSP Controller tested with motor drivers and mechanical limit switches.
Laser/PSU, Optical limit switches, and Hall Effect limit switches still need to be tested.
Supervisory subsystem:Most of the components have been acquired and are ready for breadboard testing.
ICs for Linear fan control are on order from Maxim.
Code still has to be written for the I2c and SPI components and tested.
Cooling:All components on hand, ready for testing
Optics:Mirror and Lens mounts have been wet sanded with 400 and 800 grit but still need to be sanded with 1000 and 1500 grit then buffed.
Other tinkering:Two RF CO2 Lasers (20w and 30w) have been acquired but will likely require repairs before they can be inserted into the V3 design.
Two RF CO2 laser power supplies have been acquired; one of which contains a HENE Laser, laser power meter, and cooling system.
The mailman has been delivering packages every other day or so and the UPS guy drops the package near the house then runs
. Below are a few of the items which have arrived for this build.
1x Commerical DSP CO2 Laser Engraving/ Cutter Controller
2x 1-Axis CNC/ Laser Machine Stepping Motor Driver (TB6560)
1x pack of 5 Mini 2DPT DC 5V Relay
8x 120mm Yate Loon D12SH-12 Case Fan - Black (88 CFM, 40 dBA)
3ft Tygon Silver Antimicrobial Tubing 1/4in. ID 3/8in. OD
4ft Tygon R3603 1/4in. ID 3/8in. OD Laboratory Tubing
4ft Tygon A-60-G Norprene 1/4in. ID 3/8in. OD Tubing
8x Bitspower 1/4in. Compression Fittings for 3/8in. OD Tubing
100ft 18AWG Stranded Hook Up Wire UL Approved - Black
100ft 18AWG Stranded Hook Up Wire UL Approved - Red
50ft 18AWG Stranded Hook Up Wire UL Approved - White
50ft 18AWG Stranded Hook Up Wire UL Approved - Orange
50ft 18AWG Stranded Hook Up Wire UL Approved - Green
50ft 18AWG Stranded Hook Up Wire UL Approved - Yellow
50ft 18AWG Stranded Hook Up Wire UL Approved - Blue
50ft 18AWG Stranded Hook Up Wire UL Approved - Purple
50ft 18AWG Stranded Hook Up Wire UL Approved - Gray
50ft 22AWG Stranded Hook Up Wire UL Approved - Yellow
50ft 22AWG Stranded Hook Up Wire UL Approved - Red
50ft 22AWG Stranded Hook Up Wire UL Approved - Black
16ft Custom 1/8in. Expandable Sleeving
16ft Custom Non-Fray 3/8in. Expandable Sleeving
16ft Custom Non-Fray 1/4in. Expandable Sleeving
6ft Black Heatshrink Tubing 1/4 inch
6ft Black Heatshrink Tubing 1/2 inch
2ft Red Heatshrink Tubing 1/4 inch
Kent Display - 240x160x2.9
Sparkfun Breakout Board for Kent Displays
ScreenKey Development Kit - TFT100
ScreenKey Mating Connector
Optical Dust Sensor
Mating Connector Housing for Dust Sensor
Crimp Pins for Dust Sensor Connector
ProtoBoard - Rectangle Wired 3"
USB Female Type B Vertical Breakout Board
DFRobot Arduino Mega with ATmega 1280
Keling KL17H247-168-4B bipolar stepper motor
Lin Engineering 4218L-08S-01 bipolar stepper motor
Lin Engineering 4218M-01-31 bipolar stepper motor
Lin Engineering 4218L-01-10 bipolar stepper motor
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Saturday, April 24th 2010 - 7:53 PM
The three holes on the back side of the panel, which secures the mirror, are sized to fit M3 bolts/setscrews. Since the goal for these mounts was to be as inexpensive as possible, having ultra fine pitch adjustment screws would be too expensive. The thumbscrews on lightobjects mounts are standard m3 and people seem to be pleased to the adjustment resolution. At this point, this design is still just a concept and it will remain that way, while I work on some higher priority projects, such as the supervisory subsystem.
The supervisory subsystem is a microcontroller that will monitor the DSP Controller as well as the overall system health and react to ensure the system is safe and easy to use.
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Friday, April 23rd 2010 - 3:07 AM
Despite having nine acrylic pieces, the design is quite simple.
The three holes arranged in a triangular pattern allow the mirror angle to be adjusted precisely.
Hopefully the pictures are more helpful than a lengthy description.
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Tuesday, April 13th 2010 - 10:48 PM
I’ve looked at both of those quite extensively; I almost purchased the Thorlabs mounts. The mounts I designed are not only light, they are also very inexpensive. For the cost of one Thorlabs or lightobjects mount you could get enough of my mounts to setup an entire laser system. One feature that most commercial mirror mounts lack is a cover or enclosure. It seems to me that the mirrors would last longer if they had some form of enclosure to protect them from dust.
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Sunday, April 11th 2010 - 5:48 AM
I’ve been playing with some new designs for the X axis. The X axis belt system has been redone to be more discrete.
I haven’t been thrilled with the aesthetic appeal of the light objects mirror mounts so I thought I might have a go at designing my own. These are still just gen 1 concept designs but they appear to be viable option.
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Sunday, April 11th 2010 - 5:09 AM
The two T shaped pieces which are mounted in the middle act as belt guides and belt tensioners. Tension is adjusted by sliding them forwards or back; they can be adjusted for approximately +/- 200mm of belt. Instead of flanged washers I prefer to use belt retainers between two bolts; this ensures that the two bolts are parallel and the belt won’t become angled. I’ve attached a rendering in which the belt retainers are visible. There over 1900 parts in the assembly so I often hide parts to speed up navigation and rendering.
Your sketch/design should work very well. Depending on the weight of your cutting table you may need to support the pieces on two sides. One concern I have with my design and yours is the belt sagging between pulleys.
I haven’t posted much detailing the electronics section in the enclosure. I’m still in the process of creating 3d models for a few of the electronics so it may appear rather bare at the moment.
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Tuesday, April 6th 2010 - 2:20 AM
The project goal is to build a complete CNC laser cutter/engraver for under $2500 out of pocket cost which meets the following criteria:
Work area of at least 24”x36”x8”
Simple and user friendly
Modular design for future upgradeability
Supervisory Subsystem
There will be three versions (so far) their features are as follows:Version 1 “
Up & Functional”
Laser Source:
Chinese 40w CO2 Laser Tube
High Voltage Laser Power Supply
Electronics:
Controller: DSP Laser Controller
Motor Drivers: TBD
Power Supplies:24VDC 14.6A Switching Power Supply
Linear Mechanics:
V Groove Rail with V Groove Bearings
Sensors/Interlocks:
Emergency Stop Switch
Door Open Interlock
Air Quality Interlock
Coolant Pump
Coolant Flow
Air Assist
Blower
Cooling:
Laing DDC Pump with Tachometer output
EK-Multioption RES 100 Rev 2
Version 2 “
Aesthetics & Automation”
Features/Improvements over previous versions:
Visible Aiming laser
Internal Panels
Enclosure Panels
Version 3 “
Redesign & Rebuild”
Features/Improvements over previous versions:
30w+ RF CO2 Laser
THK or similar rails
Internal or external dedicated backup power supply with AVR (Automatic Voltage Regulation)
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. The solution: three 2 terabyte drives which will bring my total storage space up 11.5 Terabytes (including the backup drive array). While the server is moving files to the new drives I figured I would get a few pictures taken of the frame which the laser will sit on top of. 
