That's really cool. Hopefully what is happening in Spain will spread to South America, too.by Forrest Higgs - General
Wow! I don't know what happened but both fab@home and reprap's alexa ratings both just took off like a turpentined cat. Huh, my little Tommelise website just did the same thing in a more modest way. I wonder if the Sparkes article has hit the pavement?by Forrest Higgs - Developers
Torze Wrote: > > A question: Kit will have all the necessary one? , > that is to say, motors, boards... > Yes.by Forrest Higgs - General
No need, Zach. I've made sure that Adrian's got the dimensions he needs.by Forrest Higgs - Developers
Oh yeah, there is one other difference between the GM3 and the plastic gearmotor that Adrian specified for the MK II. The GM3 has a 224:1 gear ratio while Adrian's motor has a 200:1. I regularised all the motors in Tommelise to 12v and use a channel on a 754410 dual H chip to drive it instead of a power transistor like RepRap uses, iirc. The GM2 can be ordered in either 6 or 12v. Since I runby Forrest Higgs - Developers
This looks great, Zach. One little heads up, though. The gearmotor that you buy from Pololou is not exactly the same one as Adrian used in the Mk II extruder. While it has exactly the same gearbox, the drive shaft is a bit sturdier (larger) than the one that Adrian used and will not mate with the coupling that comes with a Mk II parts set printout.by Forrest Higgs - Developers
_______________________________________________ I unintentionally made a watertight container this afternoon. A bit more detail is reported in the Builders' Blog and on my own website. I guess I might as well get the shotglass milestone out of the way now. Developers mailing list Developers@reprap.orby Forrest Higgs - Developers
You guys do know that the 0.5 mm channel to the external side of the extruder needs to be very, very short ... less than a millimetre if possible. Otherwise the friction in the channel makes it very hard to pump any polymer.by Forrest Higgs - General
Putonghua (Mandarin) is not much worthwhile. The Chinese have been pushing English as a second language to an extent to where I understand that there are more Chinese learning English than there are speaking it as a first language in the rest of the world. Spanish and French speaking countries have been somewhat more resistant to learing English as a commercial language so they might be good caby Forrest Higgs - Developers
Long series metric drill bits are kind of hard to come by in the States. I got some 3 mm drill bits to drill the PTFE block I use for a Mk I thermal barrier from a florida firm, IIRC. I only had to drill a 1 inch hole, though. ----- Original Message ---- From: Adrian Bowyer To: developers@reprap.oby Forrest Higgs - Developers
Good work, Zach! ----- Original Message ---- From: RepRap Forum Mailer To: developers@reprap.org Sent: Tuesday, April 10, 2007 3:55:35 PM Subject: parts db progress... Author: ZachHoeken Username: ZachHoeken (ool-18bab6f6.dyn.optonline.net) Subject: parts db progress... Forum: Developers Linkby Forrest Higgs - Developers
***As an aside, have you ever made a drill bit from drill rod? I think it might be a good way to make the extra long 3 MM drill bits we're going to need now and then. I think I need some because the 3MM extra long milling bits I ordered a god-damned month ago haven't arrived yet. #&%!!!!*** 1/8 inch is 3.175 mm. Why don't you buy one of those in a long length, wrap a couple of thicknesby Forrest Higgs - Developers
LOL! Something like this, hey? :-Dby Forrest Higgs - General
***p.s. I imagine if you are ever desperate you can cut the head off a bolt, grind it smooth, and cut a slot into the top.*** What's to stop you, aside from machinery aesthetics, from just using a standard M5 bolt that's longer than that hole it sits in and let the top stick out? :-) ----- Original Message ---- From: Sebastien Bailard To: developerby Forrest Higgs - Developers
LOL! Like I got $15,000 to plunk down for a commercial machine, never mind the highway robbery they want for the reels of filament feedstock. :-) ----- Original Message ---- From: Adrian Bowyer To: developers@reprap.org Sent: Tuesday, April 10, 2007 12:54:49 PM Subject: Re: stepper motor Quoby Forrest Higgs - Developers
$30? ----- Original Message ---- From: Zach 'Hoeken' Smith To: Forrest Higgs Cc: Adrian Bowyer ; developers@reprap.org Sent: Tuesday, April 10, 2007 12:43:26 PM Subject: Re: stepper motor sarcasm aside, automation direct has some pretty good prices on steppers for the states... NEMby Forrest Higgs - Developers
Awesome prices! ----- Original Message ---- From: Adrian Bowyer To: developers@reprap.org Sent: Tuesday, April 10, 2007 12:15:30 PM Subject: Re: stepper motor Quoting Zach 'Hoeken' Smith : > hey, > > from the BOM, i found the stepper motors, but i was wondering what sizeby Forrest Higgs - Developers
As you can see with the work that Vik and I have been doing, it's very much one thing to have a "working" 3D printer. It's quite another thing to have it print things nicely or even at all.by Forrest Higgs - General
***Short for grub screw - that is a screw with no head, but with either a cut for a screwdriver blade or a hex cavity for an allen key in the end. What's American for that?*** set screw and less commonly, headless screw ----- Original Message ---- From: Adrian Bowyer To: developers@reprap.orby Forrest Higgs - Developers
***I'm going to have a go at a laminated A1 RepRap poster Forrest, which I'll airmail to you in a cardboard tube. **** Perfect! That's just the sort of thing I'd like to be able to put up at the booth. Thanks, Adrian! ----- Original Message ---- From: Adrian Bowyer To: developers@reprap.orby Forrest Higgs - Developers
Good spot, Fernando! :-)by Forrest Higgs - General
I don't think we use anything like those kinds of frequencies on the controller boards that we are currently making. The PIC that I'm using has a 20 MHX external clock that could be hyped up to 48 MHz. Nowhere near hundress, though. The rest of the traces rarely get above the low KHz. Mind, what you've described would rather limit the usefullness of the print your own boards thing using eutecby Forrest Higgs - General
Extra distances? I was talking about increasing the cross-sections of the traces. Tell me more! Also, how high are high frequencies?by Forrest Higgs - General
No biggie. Just use ten times more solder in the traces. :-)by Forrest Higgs - General
Building a solder extruder is my next big project after I have Tommelise printing acceptably.by Forrest Higgs - General
One little mistake in your calculation. You don't pay an average rate for electricity for additional usage, you pay the marginal rate. Right now my marginal rate for electricity set by the state utilities board is $0.224/kwhr thanks to the huge sense of environmental awareness that this state is afflicted with. 432 x 0.224 = $96.76 :-sby Forrest Higgs - Plastic Extruder Working Group
***how do materials such as ABS and PP stack up against it in this regard? *** ABS and HPP have slightly lower coefficients of expansion, not enough to be significant, though. ***perhaps this is why the Strat keeps the entire build chamber at a high temp.*** Given that ABS melts at about 105 I'm left to wonder just how hot that build chamber is being kept, especially since I understand from bby Forrest Higgs - Plastic Extruder Working Group
I'm grinding through how to handle thermal contraction during the fabrication of HDPE artifacts on the Tommelise printer right now. The fact that plastics have a substantial coefficient of expansion means that it's really hard to extrude them on a flat surface and have them not peel up at the perimeter. For HDPE, for example, the coefficient of expansion runs something like ~4 x 10^-5 mm/mm/dby Forrest Higgs - Plastic Extruder Working Group