Curse and/or bless you and your powers of coding! With regards to the laser power, galvos are usually made for laser shows, so they can generally handle whatever you can throw at them. A glass mirror needs a decent amount of power to reach it's damage threshold (though similar ranges as compared to UV curing). To get around this, you have the focal length of the laser be somewhat long, and the galvos set far away from the surface, or you run it through a lens afterwards, or both. Even cheap ebay galvos can withstand 1W lasers - damage is based much more on dot size than diode output.
As for swapping out mirrors, the cheapest type of mirror is an aluminum coated mirror, which just happens to be perfect for visible light and near-UV wavelength (around 400nm to 20um). So buying an ebay galvo would work well for this purpose. If you feel like dropping the cash and playing around with this, go for it - though using a cheap laser pointer would probably be good for testing. Half a watt of any laser source can fry your eyes real quick if it goes in the wrong place.
If you're curious where I got my lasers from, it's from this shop. They're gutted from Blu-ray burners, and placed into a heatsink housing with lenses and a driver.
I may build the delta-bot anyway, since my old prusa mendel could use an upgrade and I could use the delta-bot to prove out the laser system before dropping money on galvos and other bits. But I really think there's promise with a true SLA system - apart from the material cost, the machine cost is fairly low, and resolution is orders of magnitude better than FDM. Even using non-reprap parts such as leadscrews and linear guide rail extrusions. right now my (preliminary) BOM for this design consists of:
RAMPS board, plus DAC costs: $150, ultimachine
Arduino: $50ish
80/20, frame materials: $50-$75, 80/20
igus bearings/guide rails: $80, igus
Laser diode w/ collimating lens: $100
galvanometer: $120, ebay
Stepper motor: $15, phidgets
fasteners, thrust bearings, leadscrews, etc: $50-$100, mcmaster
build platform material: $50, aluminum, mcmaster
Build bed material: $30, borosilicate glass
Teflon/FEP adhesive sheet: $30, CS Hyde
photo enlarger lens: $30 (usually you can find these cheap and/or free from old enlargers)
So even considering that I'm not using reprapped parts, this still comes out to a build cost of about $800 - bump it up to $1000-$1200 for me, since I'm probably gonna fubar a few parts first and/or blow a diode or two.
If you end up getting a set of galvos and getting something working, let me know! I'm a bit broke right now, or I would consider donating/splitting the cost with you or something. Maybe in a week or so when I get another paycheck.
Thanks!
As for swapping out mirrors, the cheapest type of mirror is an aluminum coated mirror, which just happens to be perfect for visible light and near-UV wavelength (around 400nm to 20um). So buying an ebay galvo would work well for this purpose. If you feel like dropping the cash and playing around with this, go for it - though using a cheap laser pointer would probably be good for testing. Half a watt of any laser source can fry your eyes real quick if it goes in the wrong place.
If you're curious where I got my lasers from, it's from this shop. They're gutted from Blu-ray burners, and placed into a heatsink housing with lenses and a driver.
I may build the delta-bot anyway, since my old prusa mendel could use an upgrade and I could use the delta-bot to prove out the laser system before dropping money on galvos and other bits. But I really think there's promise with a true SLA system - apart from the material cost, the machine cost is fairly low, and resolution is orders of magnitude better than FDM. Even using non-reprap parts such as leadscrews and linear guide rail extrusions. right now my (preliminary) BOM for this design consists of:
RAMPS board, plus DAC costs: $150, ultimachine
Arduino: $50ish
80/20, frame materials: $50-$75, 80/20
igus bearings/guide rails: $80, igus
Laser diode w/ collimating lens: $100
galvanometer: $120, ebay
Stepper motor: $15, phidgets
fasteners, thrust bearings, leadscrews, etc: $50-$100, mcmaster
build platform material: $50, aluminum, mcmaster
Build bed material: $30, borosilicate glass
Teflon/FEP adhesive sheet: $30, CS Hyde
photo enlarger lens: $30 (usually you can find these cheap and/or free from old enlargers)
So even considering that I'm not using reprapped parts, this still comes out to a build cost of about $800 - bump it up to $1000-$1200 for me, since I'm probably gonna fubar a few parts first and/or blow a diode or two.
If you end up getting a set of galvos and getting something working, let me know! I'm a bit broke right now, or I would consider donating/splitting the cost with you or something. Maybe in a week or so when I get another paycheck.
Thanks!