[Peter’s] been hard at work designing an affordable Selective Laser Sintering (SLS) 3D printing platform. We first saw his work on this back in April when he was working mostly with acrylic. Now he’s moved on to a design that relies on hardboard which has resulted in a build that comes it at around $20 including the motors.
The design uses a dual z-axis table for the feed stage and the build stage. That is to say, as the powder is fused together by the laser the platform it is on is lowered. Next to this platform, the feed platform is raised, allowing the power to be swept onto the build stage. This setup is moving in the right direction, but we’re still waiting to see what works when it comes to adding the laser and sourcing the powder.
both hyperlinks go to the old article. :/
http://builders.reprap.org/
Thats got the info
What I could really use is something like this with a laser capable of sintering powdered ruby (corundum). They do it with diamond for heatsinks at Sandia Labs. I have a design that I want to print custom corundum bearings, but I’d need a 100k$ sintering furnace to make them!
Could this be adapted with a superlaser to sinter corundum? I’m aware of the stress impartation this method would incur on the structure as a whole. It’s experimental.
hi folks,
neat to see this up here! the direct link is: http://builders.reprap.org/2010/06/selective-laser-sintering-part-6.html
the real innovation in this part of the project is that, keeping with the idea of trying to make 3D printers accessible and affordable, this aspect of the project designs and constructs dual z-axis tables for only around $6 in parts (and less than $20, with the motors), and replaces a lot of the traditional “vitamins” (or non-reprappable parts) that you have to purchase or can’t easily construct using rapid prototyping methods with ones that you can (and this idea is embodied in this new design’s use of a captive nut and bolt in a laser-cut gear system as the lead screw mechanism).
the design files are open source, and available on thingiverse (linked through in the reprap builders article)
happy reading! :)
random but pertinent fact i learned about lasers last week. I was talking to an optics guy with a PhD in Physics last week about the new wickedlasers 1W handheld blue laser, and also asking about military laser technologies, which use infrared. He mentioned that in many ways, the blue laser is more dangerous. This is because, being visible light, the eye has a tendency to automatically notice it, focus on it, and track it. That means that the eye will focus the beam in the most destructive way. He also mentioned that because of the way our foveal system works, your eye will keep darting around to gather the whole scene, and in the process it will keep moving that focused blue laser all around destroying everything in the process.
The military uses infrared lasers because of their power and ability to penetrate the atmosphere, and the nice thing is that since your eye doesn’t focus on it, the interior of your eye stays relatively undamaged. It will burn the surface of your eye much like a sunburn, which is still bad but seems to be a lot better. You’re also more likely to turn away from that, whereas we have evolved to turn towards and focus on visible lights.
So keep that in mind when lasering! I mostly bring that up, because my first thought was that the new blue laser would be great for this, until i realized that the reflected light would be way more dangerous than infrared!
Its probably best to use an infrared laser coupled with a low power visible laser, though again that would draw your eye towards reflections. High powered lasers are just dangerous no matter how you use them!
-Taylor
Weird how I see wooden constructions with electronics everywhere lately, it’s back to the beginning it seems.
@taylor that sounds a bit odd since if the military use a laser it will be pointing at their focus of attention obviously, and often looked at through lenses that make the area viewed even smaller.
And I think they use IR to not be noticed, but they use green too, in fact they used green lasers to warn cars to stop approaching when a untrusted vehicle is heading towards checkpoints in iraq, and I assume afghanistan and such too.
I guess my question would be: How do you get a 1 Watt laser legitimately when it anything other than 5MW or FDA approved lasers are not approved for import? Can you get an application from the government to import these things?
Is it me or does this kind of remind you of a wooden erector set?
@Whatnot Wood (or wood product) are some of the better materials a laser cutter will cut. Especially for building a structure. Acrylic shatters and cracks too much.
@Taylor Alexander: I don’t think anyone that has at least a wee bit of sense would operate a laser like that without protection. Personally I would run it in an enclosure and view it via a camera but then again I’m seriously paranoid when it comes to lasers.
@Whatnot
Sorry, I meant to clarify – I meant the new high powered laser weapons for destroying missiles that are in the 10-100KW range. Those don’t need to be visible, just powerful. I’m sure the military uses low powered visible ones for all kinds of things too.
@Chuckt
Anything greater than 5mW has to have specific safety features, that’s the only requirement. Plenty of chinese models don’t have those features, so they get confiscated by customs, but as long as a laser has those safety features, there is no limits on the power of a laser a person may own.
@sneakypoo
Well, that’s the scary thing… WickedLasers just started selling a 1W blue laser pointer for $200… previously that price would only buy you 20mW, so people had to be careful, but mostly just with direct exposure or reflections off shiny things. With the advent of low cost 1W lasers, more people need to be made aware of the severe damage these things can cause, because even a reflection off a while wall can blind you! Some kid might buy one because its “cool”, but at these power levels, they’re insanely dangerous.
Sadly, I expect that the 1W laser pointer will result in at least 20 dumb kids getting blinded or blinding others before some sort of regulation is put into effect. These are more dangerous than handguns.
The new laser at WickedLasers is not likely to be 1 watt. Most of the lasers that they sell are way overpriced and underspec. They haven’t even finished research and development yet! I have a 50mW (non-fda-approved) that I got for $20 online. In fact, you can build a >1W laser easily for $100 with those new diodes from that laser projector.
In response to Taylor Alexander, for $200 you could buy a 200mW+ laser before and wickedlasers’ new blue is probably only going to be 500mW. These are not more dangerous than handguns, but they should require a license. Good thing WickedLasers sends you a free pair of protective glasses!
Oh, and I built my first 200mW bluray laser at 16 for $150 so it’s not that difficult or expensive.
Go to laserpointerforums.com if you want to join in the discussion. There are some really intelligent people there.
More dangerous than handguns you say?
Now I want one even more so I can build laser weapons to defend my home, errrr…hunt…with.
A lower powered laser pointer could still be used as a sighting system until you want to use the more powerful one.
…for hunting…
( i just posted a video of the first test of this dual z-stage:
http://builders.reprap.org/2010/06/whoah-it-works-inexpensive-dual-z.html )
Ok who ever said that a visable laser is more dangerous than an IR laser is plain wrong. You had to have misunderstood your optics friend. The danger of lasers can be related to exposer time and Lens transmisivity. UV lasers on one end of the spectrum will not transmit through your lens but will photo-ablate it (read about Lasik). Visable lasers (somewhat in the middle of the spectrum) are just that, visable, the first rule a laser guy will ever tell you in the safety brief is “if you see a flash in one eye, don’t try to see it again with the other eye”. Typically one would see the flash and turn away. Your body also has a natural blink response to these types of events (ever have a flash light fhashed in your face?). Thus minamizing exposure to a small limited area. IR lasers on the other hand are again invisable (like UV lasers) but even worse is the fact that the Lens of your eye not only will transmit the IR light but will focus it on your retina. And this is the worst part, since it’s invisable there will be NO BLINK response meaning, you won’t see a flash if your lucky you’ll notice your vision getting dimmer. Either way Perm damage without you noticing.
The advantage of IR lasers is that you can use safety glasses that are clear in the visible spectrum, but opaque to IR light.
Cola (the beverage) works the opposite way – black in the visible spectrum, but clear to IR.