Hey guys, so, I just got to the point where I tried to get a toolchain established. I'm using RAMPS v1.2 and I managed to get tesla/tonokip's firmware working. After dealing with Arduino's stuff I got to the place where the wiki says to enter the provided values in the pins.h file. So, the first thing I did was replace what was in pins.h with what was in the text box labeled "RAMPS v1.1 and latby makeme - Firmware - mainstream and related support
If you made a LOM Reprap could you still call it additive manufacturing? Seems like that's subtractive, with all the associated waste of materials.by makeme - Mechanics
Yeah, as long as the coefficient of expansion of the outer piece is lower than the COE of the inner piece, the increase in temperature will cause the innner piece to seal itself against the outer piece. The COE of the plastic seems about four times that of the metal.by makeme - General
I've been brainstorming that idea. The biggest problem I've run into is that you would have to move against gravity at the same speed and precision you normally move horizontally.by makeme - General
Pololu has a DC-DC converter that can step 12v up to 24v at 2A and is smaller than a quarter. It can also be fixed to output 30v (if you order a lot).by makeme - RAMPS Electronics
Hey, thanks a lot! I appreciate you taking the time to break it down for me. As long as every component can handle a higher voltage, are there any negative side effects? It seems like it makes everything work better while also making things somewhat less likely to overheat. Power supplies are probably a bit pricier and/or more rare, but why isn't this a normal thing?by makeme - RAMPS Electronics
Oh, yeah, that's cool! I've never seen a flexible auger before. I wonder how well they work when they're moving around constantly. Maybe you could build a big box for holding lots of granules, and mount a Mendel on top of it (desktop height). Then a tube could pull granules up from the box while following the print head around. You'd still need a heavy extruder to actually mash the granules thrby makeme - Plastic Extruder Working Group
Okay, so you can't limit the current to the FETs like to the steppers? I didn't see a way to do that but I'm not particularly good at reading schematics either. If I've got this right then the Arduino is supplying the logic voltage for everything because it's got the USB connection. So, you can run up to 30ish volts into the shield as long as you 1) limit the current going to the steppers and 2)by makeme - RAMPS Electronics
Yeah, I read that paper, and I've seen the growing media extruder, and I even saw some group over in Europe (don't remember what they were called) who had a little funnel on top of a moving granule extruder. I still think it's too impractical. And the primary reason is still based on the amount of plastic being pushed through the nozzle more than anything else. What's the point of all that addedby makeme - Plastic Extruder Working Group
Right, so, assuming you don't raise the voltage over the Pololu's max, can you just change the input voltage the board is getting? From the comment on the wiki it looks like you can put more than 12v into the board itself without any problems, and as long as you don't go over the max voltage of the stepper drivers the performance of the steppers will be improved (also limiting the current). Areby makeme - RAMPS Electronics
It just seems like a granule extruder is drifting much closer to an industrial machine than a desktop machine. I mean, turning granules into something else is an industrial process. The up-front investment and ongoing operating/maintenance costs only seem justified if you're working with plastic in bulk quantities. Even running a 3d printer 24/7 won't use up plastic fast enough to justify any ecoby makeme - Plastic Extruder Working Group
The RAMPS wiki says you can run up to 32v into the shield as long as you don't install the diode. And Brent Crosby has shown that you can get some significant benefits from running 35v through the steppers on a Cupcake. I was wondering what it would take to run more voltage through the steppers on a Mendel with RAMPS. Can you just put 35v into the power block instead of 12v?by makeme - RAMPS Electronics
Based on the assumption that the belts I got have a different geometry, I ran a few iterations of Erik's parametric timing pully script and ended up with a pair that fit the belts perfectly. For what it's worth, the belts I have say "Gates Powergrip" on the side.by makeme - General Mendel Topics
True, but it does significantly increase the complexity of the equipment. I'm never ever going to argue that throwing more money and expertise at something won't improve its functionality. I'm just curious whether or not it's a high-value addition. The whole point of the Reprap project is to do 90% of what the expensive machines do but for 10% of the price. It's a question of tradeoffs. For exaby makeme - Plastic Extruder Working Group
It seems like one of the important features of a stepper extruder is that it can pull the filament backwards and create a negative pressure that sucks the molten plastic back into the nozzle. You wouldn't be able to do what with a broken filament (stack of plastic beads); you'd only be able to reduce the pressure to zero. Additionally, it seems like the stack of beads would be unpredictable. As tby makeme - Plastic Extruder Working Group
I've looked at them before. They seem too expensive to be worthwhile. Nothing you couldn't do with some nichrome wire or a PCB covered in kapton tape for 1/10 the price.by makeme - General Mendel Topics
I think 5mm is 0.197", which is even closer, which is why I thought maybe the files were slightly off scale or something. It doesn't seem like it should be a significant enough difference for a properly sized 5mm pitch pulley to not work with a .2" belt. But after scaling them up until the belt meshes the teeth are still thin enough that they can leave some play. So, maybe the standard Mendel tiby makeme - General Mendel Topics
nophead Wrote: ------------------------------------------------------- > They mesh with 5mm pitch belt, so > they wont be correct for 0.2". Okay, so, in the Mendel build file where it says "RepRap attempts to print its own parts wherever possible. This includes toothed drive pulleys. 5 mm pitch (or imperial equivalent XL pitch, 0.2")" it doesn't actually mean you can use .2" pitch belts?by makeme - General Mendel Topics
So I thought I'd be able to start putting all the parts I've printed/purchased for a Mendel, but I noticed that most of the gears aren't meshing properly with the belts. The build file spreadsheet specifies 5mm or .2" belts and I know the belts I got are .2" pitch because they have exactly the right number of teeth for a given distance. The gear that seems to work is the drive-pulley_3off and thby makeme - General Mendel Topics
What about this stuff?by makeme - Plastic Extruder Working Group
Has anyone tried just dousing a metal extruder in spray-on PTFE instead of inserting a PTFE tube into a metal support? This stuff Claims up to 450*F/240*C, which is basically high enough.by makeme - Plastic Extruder Working Group
Not a bad idea. The hard part would be getting a design that was flexible enough to tolerate errors in printing. If the positioning system isn't precision the bot can't do what you want it to do. On the other and, if you combine a sloppy positioning system with a closed-loop control system the bot might be just as good. Maybe you could use those indicator strips inside printers. They have a tonby makeme - Kartik M. Gada Humanitarian Innovation Prize
Doing anything except the one-layer-at-a-time method would required skeinforge to treat the extruder nozzle like a tool head. Things are about as simple as they can get at the moment because there's nothing for the extruder to run into; everything is below it. That means nothing really matters except the position of the table and how fast the extruder is extruding. If you want the extruder to priby makeme - Kartik M. Gada Humanitarian Innovation Prize
I suggest asking those questions at the cnczone instead. They have more accumulated expertise in building custom linear motion projects.by makeme - General
Maybe you can get a non-profit started.by makeme - General
> RepRap is a free OPEN SOURCE project. If we wanted > to get as many people involved as possible, we > COULD choose to sell parts at materials and > utilities cost only. Maybe throw in the hours to > tweak/setup as well. No, if the goal was to maximize participation the design would be altered to be dramatically more user friendly. Along the lines of the difference between this:by makeme - General
mlagana Wrote: ------------------------------------------------------- > what > specifically about the ToM has given you issues? > faulty parts? not following the manual? human > error? (in which case don't worry most hiccups are > human error) The first thing was faulty parts. The current theory is that some of the Kysan DC motors (not the highest quality thing in the world) haveby makeme - General
ata0921 Wrote: ------------------------------------------------------- > You simply hit print > and walk away to come back to a set of parts > (given that you have it tuned to do so). You > aren't really doing any work other than pressing a > button. Well, yeah...but that's kind of like saying an author shouldn't charge more for their book than the paper costs.by makeme - General
No. I put all the information necessary to evaluate my $0.02 in the post, so there's nothing ironic about it. When you can come up with mean time to failure numbers that compare the Mendel to the TOM you'll have something to add. Until then all any of us have are anecdotes. I shared mine, and summarized the ones I hadn't personally experienced. What did you contribute?by makeme - General
I think the current estimate is that it takes 50 hours of non-stop printing to get all the parts for a Mendel. If someone charges $200 they're only getting $4 per hour...that is basically free. Another way to look at it is that there is currently very little about a Mendel that is average-person-friendly. Even if you get a complete kit so that you don't have to worry about sourcing or preparingby makeme - General