piranha: red origami crane (Default)
[personal profile] piranha
or has this year gotten even more relentless with exhortations to BUY BUY BUY? "black friday" (oh, the irony) seems to have eclipsed and subsumed US thanksgiving, segued seamlessly into "cyber monday", nay, cyber week, and now we're fully immersed in christmas.

it's not like i ever buy anything much (ok, this year i caved to interweave's very, very cheap back issues of spin off in digital form). in fact, the only serious xmas purchase we've made wasn't on sale, and we didn't really buy it for xmas; it just happens to provide the paramour with some much-needed time off, in which we can assemble a 3D printer kit (*bounce*).

so yeah, the advertising leaves me mostly cold; i don't even read much of it. but it clogs up my email something fierce. it doesn't count as spam because i actually subscribed to the sources. but i didn't subscribe with the notion that i'd get daily email from each of the interweave sub categories i enjoy (spinning, knitting, weaving, crafting, painting), or that canadian tire now feels it necessary to send me a preview of its upcoming flyer. which comes once a week and the sale lasts for a week. why would anyone need a preview? i bought one thing from dell a while ago, and now i am offered days and days and neverending days of deals. and it's like every single place from which i once bought something, and where i actually do not mind to get the occasional catalog, has gotten it in their mind that this means i want to hear from them every few days, if not daily.

WTF, people. you've reached total saturation. all i have to give in response is a fatigued shrug. and then i'll go and unsubscribe from you all. i'll just have to check back the old-fashioned way, by bookmarking your website and then forgetting i did that for a year or so.

it must work, this saturation coverage, or surely they wouldn't do it. it's not like actual spam which is crudely hacked together by people who got conned into buying a spam script; these sale offers have nice graphics; somebody has clearly worked on making them appealing. other people must not get tired of it, but excited to have all these wonderful opportunities to SAVE (by spending more and more). where do they find the energy? it's soon going to be a full-time job just to read all these offers.

but anyway. 3D printer!. i am psyched! been making a list of all the things i want to design and print. and that's not even taking into account that i have ideas on improvements / add-ons for the printer i want to try. and then we can use the printer to build a laser cutter. and a CNC milling machine.

on 2012-12-09 07:28 (UTC)
red_trillium: cartoon cat that says "I love cats but can't eat a whole one" (Default)
Posted by [personal profile] red_trillium
I haven't been hit too much (yet) with advertising emails. I'd say I'm only at the "mildly annoying" level.

We've got a small jewlery business, nothing that pays so we don't advertise. I've been doing Facebook updates regularly, mostly photos of new things we've made or taken up to the craft shop we've got stuff at.

Cool printer! What are you going to do with it?

on 2012-12-09 19:22 (UTC)
ephemera: celtic knotwork style sitting fox (Default)
Posted by [personal profile] ephemera
aggressive filtering - I'd rather miss the one awesome deal in n-hundred by seeing it too late when I eventually check my sales stuff folder than wade through the cruft on a daily basis.

Also, 3D printer! How awesome is that!

on 2012-12-10 03:01 (UTC)
Posted by [personal profile] flarenut
I've unsubscribed from a bunch of places. But apparently some people do give in now and again, and the best predictor of whether you'll buy is reportedly still how short a time since you bought last.

Love the 3D printer. Mine is a little finicky (I rebuilt the extruder and haven't got it tuned) but I do like playing with it. And the XYZ platform I got (shapeoko) is moving now, so I just have to finish building the laser head and the pen head, and actually bolt the rotary tool onto it, and then it will be time to build a new extruder and hot end or two for it. Whee!

on 2012-12-10 13:42 (UTC)
Posted by [personal profile] flarenut
Targeted advertising is still in its infancy, or perhaps still a fetus. Example: Pandagon, a site I enjoy reading for its liberal and feminist snark, is typically chockfull of ads for republican candidates and courses on how to pick up women. Because they haven't figured out the sign bit.

For mail with a company you do business with, it's worse, because depending on what you buy you might potentially fit in any number of marketing categories. So clearly you need to get mail for all of them.

I got a Cupcake CNC a couple years ago when they were on closeout. This fall, I made the possibly-mistaken decision to finally upgrade it to heated bed and stepper-driven extruder. The extruder I have now is just the DC-motor one with the motor replaced with a supposedly high-power stepper, and it doesn't have quite enough oomph, so I'm hoping to replace with a homebrew version or a gear-driven one (but that requires the current thing working long enough to extrude some parts).

Which one did you get? A bunch of the kits look enticing, but I can't really justify them. (And yeah, the shapeoko is straightforward, would have been moreso if I'd gotten the electronics, but I had a bunch of cheap surplus steppers lying around, so an arduino and some drivers and zoom. I also want to get a bunch more makerslide)

Will you be going for a real cutter with a CO2 tube? I am still trying to cobble something together with solid-state lasers -- I figure I can get up to 10-20 watts in fairly straightforward fashion.

on 2012-12-24 04:27 (UTC)
Posted by [personal profile] flarenut
And even if you're using extrusions, you can still fab the connectors...

DVD burners will get you something that will burn paper and thin plastic; the next step up is a blu-ray burner, which will zip through paper and char veneer (I'm running at about 500 mw). After that you go to the blue lasers that are used (with downconversion and other tricks) in some big digital projectors; those go to 2 or 4 watts a piece at the price of lousy beam shape. When I have a grand or so to spare, I want to get one of the arrays from a dead projector -- that's a couple dozen diodes in a heat sink, so if you could combine the beams you would be well into the range of a small laser engraver (and, if you could do the optics, potentially capable of about 1/10 the spot size)

on 2012-12-25 02:33 (UTC)
deane: (Default)
Posted by [personal profile] deane
"those go to 2 or 4 watts a piece at the price of lousy beam shape"

Is that why I see a collimating lens in most DIY burners? It always seemed odd to me since the whole point of a laser is that it has minimal dispersion.

on 2012-12-25 04:48 (UTC)
Posted by [personal profile] flarenut
Nope. The point of a laser is that it's coherent (all the photons are in step) and also the same frequency. The narrow beam we are used to from gas lasers is a side effect of the long cavities and relatively large beam diameter (beams spread inversely as starting diameter, give or take). Semiconductor lasers all spread out pretty strongly because the cavities are tiny and relatively short (think of the end of the cavity as a diffraction slit to a first approximation). But the beams can be in a very nice single mode with most of the power concentrated in the middle, or an ugly single mode with power scattered around, or in multiple modes with power scattered even more throughout the shape. The big 445-nm diodes have an ugly cavity end and ugly energy distribution (because they're mostly about getting as many photons out as possible, not about pretty, coherent beams).

Typically what you have in a burner is a collimating lens to make all the photons travel more or parallel in a fairly wide beam (remember, if you made the beam tiny at the beginning it would just spread out) and then a lens or focusing mirror near the business end to bring all the photons down into one tiny spot. That spot size depends on a lot of things,but pretty much the best you can do is a spot about the size of the wavelength of the light you're using. So for C02 lasers that's on the order of 10 microns, or 1/100mm. For blue lasers (405 or 445 depending) that's 0.4/0.45 micron, or somewhat less than 1/2000mm. In theory (ahem) that means your energy density at the target surface could be about 400x as high for the same wattage.


piranha: red origami crane (Default)
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