Personally, I think it'd be just as easy to program the existing motors to draw a circle, or a hill, as it'd be to add another motor specifically to draw circles. Decoding that a circle needs to be drawn would be the big thing, then the existing motors, and control boards, could be coached through drawing it using basic geometry. What would be more useful, in my humble opinion, would be the abiby Roach_S - General
Okay. Someone posted on these messageboards a link to an article on the MIT fab lab. It might be interesting to you to see what some peoples have done with that technology. One that sticks out in my mind is an indian who arranged for a milk quality tester to be made using it. The early generations, probably not so much, in my opinion, but later generations might help them get that clean waterby Roach_S - General
Okay, so the technology as he accidentally developed it doesn't scale well, while reprap will ultimately be logarithmic in its deployment. The multi-thousand dollar parts themselves are interesting. Also, if you type in the link from the video, and dig a bit, you find a list of the tools they're using. Most, if not all, of those tools are adaptable to RepRap. Both the laser cutters would be, aby Roach_S - General
Ohiomike, I took a different meaning from his words... AcidHell2, you're forgetting that the base descends with the build anyway. Granted, as the base descends, it will displace mineral oil, but if the oil is forced to fill to a certain level, and no more or less, (overflow tube like in a toilet, float valve, and circulator pump in a secondary tank,) you could possibly do it. I think it'd takeby Roach_S - General
I'd advocate using different "colors" for the different materials in the item, including some transparent "color" for a filler material, (as distinct from no material,) then using XML, or similar, to spell out what each color is, possibly with substitutes. Something along the lines of ... TotalSizeXcm == 100 TotalSizeYcm == 150 TotalSizeZcm == 55 FF0000 == 'HDPE' FF0000 == 'ABS' FF0000 == 'polyby Roach_S - General
Yes, or a mercury switch wouldn't work, or be particularly shiny, if I understand correctly.by Roach_S - General
How about copying across the prototype model, then clipping it to fit what's been printed? the last layer, or the current layer, can be drawn in in the current way, and then there are only two objects on the progress side, hopefully without actually having to build the progressing object at each layer. Please excuse me if I'm in error. I know clipping is used to not draw what isn't visible dueby Roach_S - RepRap Host
...wow. ...and not a peep until he had real progress to show.by Roach_S - General
I was thinking as follows... Old, (or new) pressure cooker, converted into a doubleboiler, (might end up using a liquid other than water for some of the plastics.) An extruder nozzle drilled into the lower edge, and an airchuck added to the lid. Fill with plastic, put on a hotplate. When the plastic is melted, attach lid, and air compressor. Express plastic until the nozzle starts spitting airby Roach_S - General
I read that thread, (to date), but I can't comment there. A livedisc would be wonderful, but I can see it hiccupping on some of the...less common... rigs. An installer, or E3 key, would be much better. Of course...if you have an E3 key setup, and your next reprap will be USB capable, natively... How about putting the E3 key together with the unit. I've long wondered why USB appliances didn'tby Roach_S - Reprappers
I've considered this. The problems I see are as follows. a. A bulk powder extruder might take up significantly more room than the hot-glue gun extruder currently being used. although I am thinking about a design to dispense talc along these lines anyway. b. The only two ways I can see to force it to extrude are one, heat it in the chamber, let it cool in the barrel enough to get a grip on it wby Roach_S - General
Yes. Digging through these boards, I've seen at least one mention of wax as a support material, and one of the regulars thinks it might be fun for casting using the lost wax technique.by Roach_S - General
Over on the developers board, (which I can't write to,) there was a comment about a certain chip not being available in a DIP format. I had a thought while reading it. Could you put circuit traces on the sticky side of scotch, or similar, tape, and use a heat gun to "solder" that to the contacts of a chip...after gluing the chip in place? Could you do so without the heat treatment? What aboutby Roach_S - General
I think I can budget this. If it's still not too late, where do I send the check? Or do you/they take PayPal?by Roach_S - General
Concerning sintering. My concern on sintering is it seems that the output would always be the equivalent of cast metal. I think maximum utility won't be reached until you can fabricate metal exibiting the properties of other forming processes. Drawn, for instance, or rolled. Would it be possible, and feasable, to force a different crystalline structure by using an induced current during the sby Roach_S - Powder Printing and Selective Laser Sintering
I could be off base, but I think the idea was to design it around the fewest resources possible. Might I recommend something? Take a scrap of your aluminum, just a scrap, melt some of your choice plastic on it, and see how easy it comes off. If it's stuck for good, using aluminum is probably contraindicated. If it pops right off, you probably have a winner. As for warping, I doubt that's anby Roach_S - General
Anyone else see advertisements for that soldering gun that cools down as quickly as it heats up? I'm guessing it'd be based on a thermocouple, myself. If so, a ring of thermocouples, with the hot "side" facing in, and the cold "side" facing out, could allow you to selectively apply heat while ensuring the ambient temperature isn't raised. Of course, now I'm talking fusing two dissimilar metalsby Roach_S - General
I'm looking at an old rackmount cabinet I bought to be a "techie mans 'curio' cabinet". (For the collection of all those toys I've collected. Firiona Vie rubber figure, Star Wars BustUps, etc.) I'm thinking it would make an excellent case, and possibly partial chassis for a cartesian robot, with room for one of my old desktop computers to spare. As for upgradability. My opinion is the thingby Roach_S - General
I have to wonder if the 3 + 2 + 1 method, 3 axis controllers, plus 2 tool controllers, plus 1 interface, might be best replaced by 3 axis controllers, one interface controller, one tool controller, and some sort of "gripper" controller to select a tool. Oh, and slots at one extreme dimension of the robot to hold tools. This would allow for more flexibility in expansion. Need a new tool, or exiby Roach_S - General
My point was that since you're going to need to manipulate metal anyway, and probably ceramic, why remove them from the design of the replicator? If it takes equal effort to design the replicator to make things that combine all three materials, or to design the replicator to not need but one of those materials to duplicate itself, you benefit from the more complete replicator. The end result isby Roach_S - General
Whoops. I need to think more before posting. It'd save on posting. Belts. I suspect it'd be easier to fabricate several dozen links to a motorcycle chain, although drawing a partially folded belt out of an elastic material would be possible. Gears. I've about decided that eventually, any decent fabricator will have to have some machining ability to mill down the laid down material to toleraby Roach_S - General
I don't know that it matters, really. Eventually, the goal would be for a replicator that can make objects from disparate materials. Even if the replicator could be made from a homogeneous material, not everything one would want from it could be. Consequently, the replicator will have to handle multiple materials, preferably without user manipulation. If after printing plastic, the thing stopsby Roach_S - General
Whoops. Wrong file format, and I just noticed.by Roach_S - Reprappers
Hmmm. Tanning bulbs. I once saw a tanning lamp incorporated into a vanity mirror in a Sears Big Book. With the publicity of melanoma, these days, I don't know if they still make the things, but the bulbs appeared to be about a foot long. (read, about .3 meters.)by Roach_S - Polymer Working Group
How straight does the inside have to be? Could you use two shorter pieces, then thread them together with nuts of sufficient length? Or would this make the aluminum too thick walled? ...Actually.. Unless the hole has to be round, you could gouge a block with a hacksaw, then affix a plate to the side. You'd need a jig to keep the hacksaw aligned with the working piece. Possibly two upside dowby Roach_S - Reprappers
I can think of some things that might work, but they'd require modifications to your equipment, (water jet alongside the bit,) or a different bit, (hollow, with a vacuum pump.) Not likely to be useful. Could channel two pieces of aluminum, then weld them... Alignment might be a bit of a problem. Actually, if you aligned them around a piece of wire, or other material that you would be able toby Roach_S - Reprappers
Was the casting core rigid or elastic? I could see the sprue technique working quite well with something that was rigid, but I can see problems with it if it were elastic. Namely stretching and tearing in spots other than the connection. Also, how viscous is the gel, when being applied? If it is sufficiently viscous, some overhang may be created without a support material. This would probablby Roach_S - Polymer Working Group
I just had an idea. Use the same material for support as you're using for everything else...then paint it with cooking spray, or some other lubricant. For hollow objects, this wouldn't work well, as the filler would persist in being too large to exit any holes, but for other things, it might. However, it'd be nice to be able to lay the oil down the sides. In this manner, you could "stack" supby Roach_S - Polymer Working Group
Granted, not the most universal solution. However...won't it melt wax as well? Are there very many, safe and available, materials that freeze at a considerably lower available energy, than they melt? If not, I think it'd be difficult to implement the filler and the main material using heat. You might make it using wax and plastic, but wouldn't the plastic soften about the same time the wax meby Roach_S - Polymer Working Group
What about gearing the motors for that extra bit of positional accuracy? It seems to me there would be two ways to go about it. One, instead of directly driving the shaft with the motor, drive a small gear with the motor, and drive the shaft with the gear. Judging from the picture, this would work for all three axes. The other method would be to drive a separate shaft with the stepper, but oneby Roach_S - General