General RepRap Questions

Hi Guys!

My name Is Leav, and i'm a mentor of a FIRST (www.usfirst.org) robotics team in Israel.

I'm very excited about the RepRap project, and I don't think I should explain why on this forum

I'm going to have my team (Highschool kids) start building a RepRap when BitsFromBytes start shipping kits again, but I have some questions about RepRap for now:

1)what is the status of the Replication? I hear Vik Olliver has managed to print a complete set of parts (sans electornics,motors and metal obviously), has anyone else managed yet?

2)Please excuse me for being rude... but what is holding the project back? seems to me that if at least 5 people have RepRaps the parts should be shooting out of them by now

3)what is the print resolution of the RepRap? I have seen the traditional shot glasses and they seem pretty crude.. but this ABS printing example seems amazingly clean and precise!
[blog.reprap.org]

I have some more questions, but they depend on your answers so i'll just wait for now...

-Leav

Welcome! I'm involved with FIRST team 1318 from Washington State, USA (did we see you at the championship last month? We were the little purple rabbit on Newton). I originally got involved with this project so that my team would be able to build cool stuff with it as well. This is a great project, and FIRST is a great program!

1. No, Vik is the only one imminently approaching self-replication.

2. Right now the project is still in the experimental phase. Only in the last several months have kits become available, and there are still a few bugs in the software. Most people with completed Darwins are still, as far as I know, testing them, and making sure that they work right. Reproduction is a low priority for most RepRappers ATM (but hopefully will soon move up).

3. Darwin, when completed to spec, is supposed to be capable of .1mm positional accuracy and an extrusion filament of .8mm diameter. However, these numbers (particularly extrusion diameter) are certainly not set in stone. There is still a lot of variety and experimentation going on, and I'm not aware of any two RepStraps being built that go about it in exactly the same way. In the end, I expect that there will be many variations on this important number, because of the tradeoff between resolution and print time.

"1)what is the status of the Replication? I hear Vik Olliver has managed to print a complete set of parts (sans electornics,motors and metal obviously), has anyone else managed yet?"

Vik has done it and is presently assembling the first daughter Darwin. Other people have printed things, but I don't think that anybody has done a complete parts set. I understand that Nophead...

[hydraraptor.blogspot.com]

is starting to seriously print Darwin parts

"2)Please excuse me for being rude... but what is holding the project back? seems to me that if at least 5 people have RepRaps the parts should be shooting out of them by now smiling smiley"

The big bottleneck right at the moment is feedstock filament. You can buy filament made of HDPE and similar engineereing plastics both readily and cheaply. Unfortunately, those have warpage problems and we haven't worked out how to compensate for that yet. The injection moulding industry faced the same problem years ago. It's possible, but it will take more time to develop the techniques. ABS warps a lot less but is a bit pricey and PCL, the original plastic for Darwin, is impossible, for practical reasons, to have made into filament. PLA does the best job with ABS a close second. Right now Vik is having a batch of PLA made into filament and will be distributing it in a few months.

"3)what is the print resolution of the RepRap?"

In theory, 0.1 mm. A lot of the pics you see are of PLA before Nophead worked out how to get good surface rendering with it.


"I have seen the traditional shot glasses and they seem pretty crude.. but this ABS printing example seems amazingly clean and precise!
[blog.reprap.org]"

It gets lots better than that.

[hydraraptor.blogspot.com]

"Welcome! I'm involved with FIRST team 1318 from Washington State, USA (did we see you at the championship last month? We were the little purple rabbit on Newton)"

Yup! we were in newton too! you beat my team (2630) 66 to 36 in qualification match #42
I loved your robot design! here is a team shot of our team: [www.chiefdelphi.com]

"(regarding the shot glasses' resolution) It gets lots better than that."

cool!

Well Seeing as BitsFromBytes should start shipping again in a couple of weeks I think we'll be ordering the Electronics soon enough.

Expect to find some questions soon in the proper Forum
-------------------------
One more question though.. How many Darwins are there?
Is it just me or are there more RepStraps than Darwins?

-Leav