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==Mechanical Parts List== | ==Mechanical Parts List== | ||
This laser welding system was derived from http://www.thingiverse.com/thing:11653 Please start there for understanding the basics of the mechanical setup. The variations we made included the following: | [[image:Laserrig_detail.JPG|250px|right]] This laser welding system was derived from http://www.thingiverse.com/thing:11653 Please start there for understanding the basics of the mechanical setup. The variations we made included the following: | ||
# We mounted the whole system in a double drawer file cabinet that we hollowed out, put on a safety switch for the laser, and new drawers with magnetic closers. A hole was drilled through the top for the wires and the fiber laser to pass through. | # We mounted the whole system in a double drawer file cabinet that we hollowed out, put on a safety switch for the laser, and new drawers with magnetic closers. A hole was drilled through the top for the wires and the fiber laser to pass through. | ||
# We extended the legs past a square bottom to allow for the cabinet rails to remain intact as seen in the photo. | # We extended the legs past a square bottom to allow for the cabinet rails to remain intact as seen in the photo. | ||
# We added a second substrate layer that slides in consisting of a metal substrate and a lower iron glass cover plate. | # We added a second substrate layer that slides in consisting of a metal substrate and a lower iron glass cover plate. | ||
Revision as of 20:11, 6 August 2012
This page describes how to make an open source laser system for polymeric welding. For directions on how to use the one located in the MOST lab see: Laser welding protocol: MOST.
Our primary interest in it is making heat exchangers by welding together layers of inexpensive polymers. This is counter intuitive, but our latest theoretical and early experimental results show that this type of heat exchanger can be very efficient as well as absurdly cheap. See: expanded microchannel heat exchangers for our latest paper. These heat exchangers can be used for all kinds of energy efficiency applications including our work to make solar powered water pasteurization systems. If we can get a system that works it will represent an extremely inexpensive method of pasteurizing water at the family or household scale.
If you use the system for other applications please let us know what they are. Happy making!
Mechanical Parts List
This laser welding system was derived from http://www.thingiverse.com/thing:11653 Please start there for understanding the basics of the mechanical setup. The variations we made included the following:
- We mounted the whole system in a double drawer file cabinet that we hollowed out, put on a safety switch for the laser, and new drawers with magnetic closers. A hole was drilled through the top for the wires and the fiber laser to pass through.
- We extended the legs past a square bottom to allow for the cabinet rails to remain intact as seen in the photo.
- We added a second substrate layer that slides in consisting of a metal substrate and a lower iron glass cover plate.
Misumi Parts
Part Description | Part Number | Link |
---|---|---|
Precision Linear Shafts | PSFJ12-480 | http://us.misumi-ec.com/us/ItemDetail/10300000120.html |
Linear Double Bushings with Pillow Blocks | LHSSW12 | http://us.misumi-ec.com/us/ItemDetail/10300028460.html |
Linear Single Bushings with Pillow Blocks | LHSS12 | http://us.misumi-ec.com/us/ItemDetail/10300028370.html |
Aluminum Extrusion Four-Side Slots | HFS5-2020-2000 | http://us.misumi-ec.com/us/ItemDetail/10302368740.html |
Square Nuts for Aluminum Extrusions | HNKK5-5 | http://us.misumi-ec.com/us/ItemDetail/10302246940.html |
Reversal Brackets with Tab | HBLFSN5 | http://us.misumi-ec.com/us/ItemDetail/10300437260.html |
Cap Screws for Aluminum Extrusions | HCBST5-12 | http://us.misumi-ec.com/us/ItemDetail/10302261460.html |
T-Shaped Shaft Supports | SHA1220 | http://us.misumi-ec.com/us/ItemDetail/10300013940.html |
Stockdrive
Part Description | Part Number | Link |
---|---|---|
18 Teeth Polycarbonate Timing Pulley | A 6T16M018DF6005 | https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=42977&GroupID=347 |
Fiberglass reinforced Neoprene Toothed Pulley Belt | A 6Z16MB89060 | https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=70713&GroupID=342 |
For the details on our laser see: Laser welding protocol: MOST
Glass cover and base
- For the base we used aluminum sheet
- Source for high transmitivity glass: SGG DIAMAN - Saint-Gobain Glass Vision Product Family -Extra clear low-iron glass
Printed Parts
- Follow guidelines from http://www.thingiverse.com/thing:11653 and print components.
- In addition you need:
- Finally we put ours in a hollowed out 2 drawer file cabinet - making a magnet safety lock on to two new doors.
Designs specs
- The projected dimensions are to be 1.5 ft. by 1.5 ft.
- The laser welder is based upon a laser cutter system found here: http://www.thingiverse.com/thing:11653
Electronics
Electronic parts
- Arduino MEGA 2650 - https://www.sparkfun.com/products/11061
- Adafruit Motroshield - http://adafruit.com/products/81
- 2x Adafruit Stepper Motor - https://www.adafruit.com/products/324
- 2x Opto Endstop - http://store.makerbot.com/electronics/electronics-kits/optical-endstop-v2-1-kit.html
- Power Supply with 5 and 12V (e.g. used computer power supply)
- MAX3323 chip (or similar) - http://www.digikey.com/product-detail/en/MAX3323EEPE%2B/MAX3323EEPE%2B-ND/1701884
- 4x 1uf capacitors
- Female Serial-Breadboard cable
- Hookup wire
- LaserMount 264
- TECSource 5305
- LaserSource 4320
- Firmware: https://sourceforge.net/projects/lasersystemforp/
Software
Safety
The Laser is composed by three main devices: LaserMount 264, TECSource 5300 and LaserSource 4320. The LaserMount 264 is a united that integrates a Peltier cooler for precise temperature control and the laser itself. TECSource 5300 is a temperature controller that needs to be attached with the LaserMount. LaserSource 4320 is a Laser Diode Driver, it controls the laser behavior such as Voltage, Current, PWM Duty Cycles and
On/Off control.
The installation of the LaserSource and the TECSource are very straightforward. After unpacking the units, make sure all packing materials have been removed and nothing obscures the ventilation ports on the side and front of the units.
Change The Voltage Selection to the appropriate value and make sure both devices are properly grounded.
The devices have vent holes on the side and front, do not block these vent holes, or overheating may occur, causing damage to the unit.
Connect the cables from the TECSource and the LaserSource labeled LASER and TEC to the LaserMount properly.
To power up the unit, connect the AC power cord to the unit, turn the power switch, located on the front panel, to the on (I) position. The unit will display the model, serial number, and firmware version, go through a quick power-up self-test, and return to the last known operating state.
In order to achieve the highest level of accuracy, the TECSource should be powered on for at least one hour prior to taking measurements.
Once devices are powered up, it is necessary to enable the External Fan Control on the TECSource menu options. Make sure the temperature controller current limit is set to a maximum value of 7.4A.
General Basic Precautions:
The LSO shall be notified of the purchase of any laser, regardless of the class. Such notification should include the classification, media, output power or pulse energy, wavelength, repetition rate (if applicable), special attachments (frequency doublers...etc.), beam size at the laser aperture, beam divergence and users.
No attempt shall be made to place any shiny or glossy object into the laser beam other than that for which the equipment is specifically designed.
Eye protection devices which are designed for protection against radiation from a specific laser system shall be used when engineering controls are inadequate to eliminate the possibility of potentially hazardous eye exposure (i.e., whenever levels of accessible emission exceed the appropriate MPE levels.) This generally applies only to Class IIIB and Class IV lasers. All laser protective eyewear shall be clearly labeled with optical density values and wavelengths for which protection is afforded.
Skin protection can best be achieved through engineering controls. If the potential exists for damaging skin exposure, particularly for ultraviolet lasers (200-400 nm), then skin covers and or "sun screen" creams are recommended.
HANDS - Most gloves will provide some protection against laser radiation. Tightly woven fabrics and opaque gloves provide the best protection.
ARMS - A laboratory jacket or coat can provide protection for the arms. For Class IV lasers, consideration should be given to flame resistant materials.
Theoretical Laser Power Requirements
Material | Spot size (mm) | Laser power (W) |
---|---|---|
Polymer | 1 | 10 |
Polymer | 0.3 | 1 |
Polymer | 0.1 | 0.1 |
Al | 1 | 1000 |
Al | 0.3 | 100 |
Al | 0.1 | 10 |
If the material is plastic wrap or aluminum foil thickness, the power required is about three times as much. So basically being able to focus the beam not only can give you smaller channels, but it also reduces the required laser power.