Hi Samuel, Actually a lot of slave and near slave labor could face competition from RepRap since it is as you note assembly line work performed to mass produce cheap commodity consumer goods for developed countries. The widespread availability of RepRap in those developed countries would put those products into competition with equally cheap customized consumer goods, a competition which they aby BDolge - General
Hi Samuel, Yes, currently changing out nozzles is a fairly simple process. The difficultty we are discussing (at least at the foundation of the thread) is that the currrent nozzle is fixed relative to the print head which maintains its' facing relative to the x/y table regardless of its' direction of travel. In the case of a circular nozzle this is irrelevant. But if the nozzle is slotted soby BDolge - General
Just a note on the (pre) existence of "affordable" fabbers. If custom manufacturing were in fact affordable to a wide base of people there would already be dozens of working RepRaps out there. The stl files for the plastic parts have been available for some time now. Anyone who can afford to can send them out to be made by any of a number of professional prototyping companies. As I recall tby BDolge - General
Colin, I think you're correct with your Wright brothers analogy, and about our need to understand our basic operating parameters, but I disagree about the usefulness of building a RepRap at this point. Each machine built is somebody else with the capability and motivation to do experiments about the way plastic acts and how to optimize code and how to integrate other materials. While I agree wby BDolge - General
Vicktor, I am sure that if RepRap gets any traction at all one of the first things to happen will be the occurrence of "regional competence-centers" or just plain community accessible machines (in libraries, churches, and community centers) which will naturally develop their own experts. Certainly in less affluent areas it would make sense for several families to share a machine and I expect tby BDolge - General
Demented, True (See I can be concise) (but I think I am doomed to be parenthetical, self-referential, and over-analytical)by BDolge - General
Hi DC, Yes and no on the complexity issue. Certainly increasing complexity goes along with increasing capability (assuming other capabilities are not traded off) but there are ways to manage complexity and decrease it's potential damage. The trick is they need to be implemented at the beginning if they are to be really effective. That's why I want to have these discussions now. The most effecby BDolge - General
Hi Victor, I was not arguing that creating shaped nozzles was impossible or even inadvisable, just that it might not be advisable to build the basic machine around doing so. While I am sure that you and lots of others are comfortable with .3 mm milling, lots more folks are not. The simpler the base machine is the farther/faster it will travel; therefor I ask what is the benefit of this complexiby BDolge - General
There are 2 issues with shaped nozzles: 1. building them- remember we want layers to be as thin as possible for more precise building, so at least one dimension needs to be as close to .5 mm as possible. It is tough to get and use drill bits in that size, much less the milling heads you need to create slots, stars, etc. Also, the material at the nozzle tip needs to be very thin to reduce theby BDolge - General
Demented: I was thinking in terms of several independently moving heads writing different parts of a piece at the same time. In that sort of situation keeping the heads out of each others way would be VERY tricky and hardware dependent. I have been thinking about infill heads, they would definitely be good areas for 2nd or 3rd stage development. My idea is similar to yours involvingby BDolge - General
Any attempt to increase print speed will have a cost. The most obvious is to increase the feed rate by raising the pressure and probably the temperature in the nozzle. The cost is an increase in price and power consumption, and probably complexity of the head. This sort of problem tends to manifest the cube/square law so that raising output from 1 to 4 will require raising price from 1 to 8. (by BDolge - General