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Re: STL Slice & Dice - Help Wanted! - 18 years ago

It's been a while since I've played with Povray but I think it's possible to create an object that's the intersection of an arbitrary object and a plane. Do that repeatedly, moving the Z of the plane and rendering each frame to a PNG. Hmm, can Povray do flat (i.e. non-camera) projections?

Re: The Canon - 18 years ago

Some RSS feeds I subscribe to:

Re: The Canon - 18 years ago

Greg Bear's "Queen of Angels" and "/" ("Slant") Fred Saberhagen's Berserker series Gregory Benford's Galactic Center series Stanislaw Lem's "The Cyberiad" Robert J. Sawyer's "Golden Fleece" Actually, just about anything by Greg Bear or Robert J. Sawyer is a must-read for me.

Re: Cat 6 Cable or maybe 5? - 18 years ago

I used wire pulled out of a disused monitor cable. Seems to work just fine.

Various Conductive Coatings - 18 years ago

These sites: have a bunch of different conductive products. Most of them probably aren't practical for circuitry but a few of them look interesting.

Re: Does anybody know the protocol... - 18 years ago

Would this thing be of any use?

Re: Does anybody know the protocol... - 18 years ago

I haven't seen anything for controlling a USB key directly from an MCU. The closest I've seen is this: Seems a bit of overkill, though. You might be able to read some sort of non-USB memory card, though. I once wrote routines to read a CompactFlash card using a 16f877. Info here: The CompactFlash interface was fairly easy but needed a lot of I/O pins. I wonder how hard an SD card would be.

Airbrush for Printing Conductors - 18 years ago

Found this: Not a lot of info in the article.

Re: Occam - 18 years ago

The article mentions copper sulfate and "a reducing agent". Interesting that they didn't mention the reducing agent by name.

Re: pyRepRap - Reprap Python Module - 18 years ago

The OLPC uses Python, right?

Re: Why Java3D - 18 years ago

I just tried profiling it using TPTP but didn't really learn anything useful other than confirming that it's creating a huge number of objects (mostly Rr2Point). Based on the conversation going on over on the main blog, it sounds like Adrian already knows the source of the problem, so I'm guessing there will be a fix shortly.

Re: Why Java3D - 18 years ago

I saw something over the weekend that makes me think that the "does it actually print" and "can it go faster" problems are becoming the same problem. Vik Olliver posted something on the main blog that implies that the host software is using so much memory that Java's garbage-collection routines are interfering with the motion of the extruder head. What Vik ran into looks similar to what I've s

Re: Occam - 18 years ago

One idea that I've been kicking around for a while is to use a two-part paste that, when combined, deposits copper. One component would be a copper compound (e.g. cupric oxide, cupric sulfate, blue vitriol). The other would be a strong reducing agent (e.g. ascorbic acid). In theory, you should be able to just mix the two in the right proportions and get a nice copper deposit. In practice, you'd

Re: Is there a chip that does this? - 18 years ago

Ah, he beat me to it. I type too slow.

Re: Is there a chip that does this? - 18 years ago

Best bet is a hex inverter (6 inverters on a chip). Connect A to the input of one inverter. Connect C to the output of that. Chain that to the input of a second inverter and connect B to the output of that. You'll be able to get 3 of these from a single IC. Part numbers for hex inverters, depending on your needs: 74LS04 74HC04 MC14069

Re: inch substitute for M5 threaded rod? - 18 years ago

Here's a table for looking up equivalents: Looks like 10-32 is pretty close.

Re: Occam - 18 years ago

Applying the technique at the board level is certainly interesting. I wonder how this could be adapted to work with a RepRap. Seems like the main stumbling block so far is finding a practical conductor.

RepRap at LCA - 18 years ago

Someone has posted pictures on Flickr of Vik's Darwin at Linux Conference Australia here: One of the photos is a bucket of printed parts:

Re: No Extruders Attached! - 18 years ago

I just tried a bunch of things to try and get the "no extruders" message. Only two things that I tried caused that error: - removing the extruder board from the communication ring (i.e. bypassing it) - changing the extruder address setting to something other than 8 The following *didn't* give me that message: - disconnecting the thermistor - removing the PIC - disconnecting power to the extru

Re: No Extruders Attached! - 18 years ago

I've noticed that the extruder PIC will stop responding if the thermistor isn't connected. It'll also do that if C3 is missing. Any possibility you've got a loose connection?

Re: How do I post on the RepRap Builder's blog? - 18 years ago

You need to get yourself invited. I don't recall if any member or just Adrian is allowed to invite members. I was a member at one time but, due to a Blogger idiosyncrasy at the time, I kept accidentally posting my regular blog entries to that one instead. I dropped out of the blog to avoid confusion. Blogger has since fixed the problem but I never bothered re-joining.

VRML Export and Viewing - 18 years ago

Re: Building the Darwin Cartesian bot - 18 years ago

Nice. Did you get the plastic parts from Ian?

Re: Why 3mm for the Feedstock Filament - 18 years ago

I'm not sure. I don't think there was any particularly compelling reason for it. In May of 2005, they were doing experiments using hand-made feedstock. There's a mention here of 4mm rod. Then 2mm here: . The first mention I can find of 3mm is this: .

Plastics Comparison Table - 18 years ago

Found this: Seems to be missing melting temperatures for some things, though.

Re: Building without instructions - 18 years ago

Curious about something: Would it help any to use adhesive paper templates? Office supply stores sell packs of the stuff, usually under the name "full-sheet labels". I've used them for various things in the past (e.g. ). I can see them being handy for something like this but they could also be a potential pain in the butt. They're hard to move once they've stuck to something.

Re: windows installer - 18 years ago

Could be that the reason it worked for me is that I've already got the 3D packages in my extensions directory.

Re: Resistance Calculations - 18 years ago

By the way, this is how I'm getting the resistance value. Open RepRap in eclipse, run Main in debug mode. Put a breakpoint in GenericExtruder, on the next line of code after this one: double resistance = calculateResistance(rawHeat, calibration); In the source I'm using, that's line 809. Open up the extruder exerciser and wait for the breakpoint. Hovering the cursor over "resistance" should g

Re: windows installer - 18 years ago

It seems to have created an empty RepRap folder in my Start menu but, otherwise, it seems to have worked.

Re: windows installer - 18 years ago

I'll try to give it a go tonight and see how it does.