How about moving the object around instead? Most parts are quite small and lightweight.by mimarob - General
Feeling extremly stupid, but then again I never where any good with 3-d problems... Which part are you trying to make? are you making a negative? Is it one of the extruder parts on: ?by mimarob - Reprappers
hmm yes but this does not make an infinite loop or? In the reprap design there is a need to run several revolvations for the Z-bed.by mimarob - Mechanics
Hello! I though I'd ask a few more stupid questions when we have an export present. Say you want to build an object of about a cubic centimeter in size. Then you need to make about 100 laminated plates. How is this all put together? One steelplate at a time? Or do you trim each plate after it has been placed on the object? How is the precision achived when aligning the plates?by mimarob - Mechanics
Sounds cool! Wonder if one could inject the plastic with an ordinary glue-gun, and if that kind of plastic would be useful in a beaded belt? It would probably make sense to make a long aluminum form since one would otherwise have to wait a long time for the balls to cool! One could drill conical inlets to each ball to make a descent fit from the glueguns nozzle, also a small scratch (hacksaw)by mimarob - Mechanics
There is a long thread in the blog about beaded belts as a replacement to the belts we presently use in reprap. Thought it deserved to be mentioned here too. I started looking around for everyday easily-available items using a string or wire and small balls spaced out evenly along side. Two things came to mind: 1) The kind of chain found hooked to the plug in a houshold bathtub. 2) Cheap plasby mimarob - Mechanics
I was thinking even more in third-world terms. If we really get reprap going then the computer might become the larger cost, we consider the computer as a commodity but maybe the usb sticks could be used as carriers of "manufacturing receipies" so reprap:ing could take place at sites which lack computers...by mimarob - Controllers
I think some kind of primitive user interface would be needed. Say the USB stick contains the receipt for one hundred different parts that are needed in the village-whatever-wherever equipment. Assuming a small malfunction and the whole thing is reset. It would be an absoulte necessity to be able to instruct the machine to start printing on item, say 63.by mimarob - Controllers
I used to have a bad concience for using two old PC's as a firewall and server at home but they probably use less juice than the new ones... Anyway I think off-line printing is a great idea. Once the first weeks reprap thrill has worn away, you might want to stove your printer away somewhere not in the middle of the livingroom floor. I have been working some with a set of small micro-controllerby mimarob - Controllers
testing the torque. Hmm if you need to meassure the torque on the stepper it might be easiest to get it connected to a rod sticking out sideways and then hang a tray with water in it on the side. The rod length X the weight of the water would give you an estimate, just remember that the holding torque is higher than what you can actually move.by mimarob - Mechanics
I'm going a repstrap path and have assembled a machine from a commercial drawing, check out It will double as a PCB drill and so far I think I spent about 500-600 USD on it, probably more.. My machine does not look so nice as this picture, but I got it together with mostly manual carpentry tooling except for the milling done in the MDF board for the slides, where I had to borrow a workshop sincby mimarob - Reprappers
More like a crash-test-dummy than a heads-up ;-)by mimarob - Reprappers
Tried the BOM generator and mouser import today, its quite impressing. First I tried the comm controller card, no problem. Next it was the stepper motor controller... Found this component to be obsoleted, never done mouser before so I couldn't quite figure out what to do, maybe there is a susbstitute item? I can otherwise be quite creative when substituting connectors when I want to :-E 53by mimarob - Reprappers
I looked again at the data sheet for the AS5035, it seems to have an "index" pin as well, it will fire at the north-south passage to enable recovery more often then when using the end-stops. I guess the endstops have to be with precision as well when using the present technique ;-)by mimarob - Controllers
Hmm, just a thought. The ics originally tested on Is the quadrature pulsed output the only option? Wouldn't it be easy to miss a pulse or two and thus accumulate a substantial error over time? It seems this has to be complememted with some kind of zero-passage detector to work out of the lab bench? The slovenian ones (just skummed briefly over the data sheets) seem to have an absolute binary pby mimarob - Controllers
Sorry I just reread your post and saw the "strap" where I previously read the "rap", so I guess I deserved a rap from the strap ;-) My latest thought was to use a cylindric housing with a large steel spring, something like you see in "space corridors" or "infectios disease"-movies. Then only have a little tent to accommodate for sideways moving of the extruder. As the plate moves downwards, theby mimarob - Mechanics
The problem would only be to get parts that withstand the heat... CAPA would make an interesting site in a 175 centigrade oven... The reason I thought the commercial machines where so expensive was that all parts had to be fabricated to withstand the temperature. Also self-replication is out of the question with that approach, parts in thermoplastic would be rather doughy ;-)by mimarob - Mechanics
As far as I understand there is an advantage since the plastic shrinks when cooling. Flat objects thus has a tendency to curl (see the builder blog btw). If the whole object is finished before cooling off less curling will occur. Hmm maybe a hot air gun could provide both the heat and the preassure to the bellows, otherwise I though I'd use a large iron spring to keep the whole thing risen. Iby mimarob - Mechanics
PWM is probably the way to go.. I'm experimenting right now with something called a "chopper". its an oscilator, a flyback connection and a current sensing resistor (1 ohm) in series with the "coil" which right now is replaced by a 4.7 ohm resistor - not ready to fry my $50 steppers just yet... The pwm:ed signal is fed to a P-MOS transistor driving the coil. It seems to be doing the right thinby mimarob - Mechanics
I've been thinking about one thing for some time now. One of the original assumptions of this project was that in order to keep the cost down for the Reprap equipment, one would not want to preheat materials, because that would mean all its components had to be made to withstand that temperature. As I understood it, this is how commercial rapid prototypers operate, by setting a bias temperatureby mimarob - Mechanics
I'm in as well, sign me up for one!!! $90 is very affordable, only the plastics, without the barrel, drive screw etc. rapid prototyped would cost more... /Erikby mimarob - Reprappers
Where did the 32 Liters figure come from, is that the size of a new cardrige??? How much did this machine cost originally?by mimarob - General
cool link, I have some friends that will start to drool, (if they have the ability to appriciate how long time it would take to reverse engineer this yourself)by mimarob - General
Just a thought... If the studding is M6, it means every whole turn will advance the position by 1mm This means that we go from a resolution of 2.5 um to 5 um. Since we are looking at extruded plastic at about 0.2-0.3 mm (200-300 um) at best I wonder if the resolution has any impact on the precision at all? /Erikby mimarob - Reprappers
Finally got it... Just select Tools => Scripts and Plugins Manager and make sure your internet is working (unlike mine ;-) Then you can download the STL plugin directly from the gui. I'm running 2.4.1 now btw! Cheersby mimarob - RepRap Host
humm obiously I've been at this before.. I found some .aoi files in my "open recent" menus, that was much better!! But I am a little surprised, tough .stl was _the_ format for model exchange...by mimarob - RepRap Host
Hello! I feel extremely stupid today, I have downloaded Art of illusion 2.4.1 running a Java 1.4.2 on suse 10.1 (i also tried it on a 9.3 suse) The problem is that when I try to open for instance the clamp.stl file that I downloaded I get a message: An error occured while reading the file: Not in GZIP format OK Anyone knows what is going on???? /Erikby mimarob - RepRap Host
aha I see, is it the "V" of the teardrop that is printed on top? So it is possible to make hollow shapes as long as the angle is not to steep (i.e 45 degrees)?by mimarob - General
Hello! Can all the plastic pieces of the carthesian be produced with only one printhead with polymorph or is it necessary to use a filler material, i.e. two heads? I'm thinking especially of the swiss-cheese corner pieces...by mimarob - General
Hello! I am new on this list. I have just surfed these papers up and down for a week or so and came up with the following questions ( or perhaps statements masked as questions ;-) Making the plastic extruder head and the 3mm plastic sticks seems doable and also the list seems to have come to some kind of agreement on how its supposed to be done? There seems to be a lot more ideas floating arouby mimarob - Reprappers