Is this and fab@home the same thing?

is a RepRap and Fab@home the same thing? Or are they two diffrent projects? If so do they share technology?

No. Yes. Not really.

Well Said Forrest.

Johnny--

Forrest gave the essential answer. Short, Sweet and to the point. Concise and elegant.

1- RepRap and Fab@Home are the same in that they are both projects attempting to produce, cheap, user-friendly, in-the-home 3D printers.

2-The difference is in what the specific project goals are. Fab@Home really only wants to construct a printer purely to print other things. RepRap, however, has a goal of creating a machine which can self-replicate itself, which then has the side effect of being able to produce useful things like the fab@home guys intend on. This added bonus means that in the long run, the machines will be cheaper.

3-Finally, Fab@Home and RepRap share technology only to the extent of how Apple and Microsoft share it; we invent something and they like it and have a look, or they invent something and we have a look.

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Jay

Thats Kinda funny considering both projects are open source. Microsoft and Mac have the problem of being competitors were RepRap and Fab@home have the advantage of being open source projects that share technology. Not sharing technology really seems kinda pointless.

JohnnyThunder Wrote:
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> Thats Kinda funny considering both projects are
> open source. Microsoft and Mac have the problem of
> being competitors were RepRap and Fab@home have
> the advantage of being open source projects that
> share technology. Not sharing technology really
> seems kinda pointless.

Microsoft & Apple can clearly see what the other has done when one of them has a new idea, RepRap & Fab@home can also, with the advantage of being able to see how everything works. Nothing needs to be actively shared, as ideas always are, and by the nature of open source the details are too

JohnnyThunder Wrote:
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> Thats Kinda funny considering both projects are
> open source.

Open source isn't the same thing as identical.

Aside from the self-replication issue, the major difference between the two projects lies in the nature of the way in which material is printed. Take a look at the deposition tools page at fab@home

[fabathome.org]

I couldn't give you a direct link that works with this forum. Click the link "Deposition tools" in the lower left quadrant of the page.

From the onset fab@home has primarily dealt with unheated syringe extruders printing with materials like silicone, for example, that can be delivered by that sort of technology.

Reprap, otoh, has developed around the Mk II extruder which is a full blown heated plastic extrusion system which uses 3 mm plastic filament as feedstock.

[reprap.org]

This technology has been through several iterations now and is rapidly approaching a mature phase where further design emphasis is on reliability and durability.

As Jay said, Reprap typically designs its printers so that a greater and greater percentage of the parts going into one can be reproduced by the printer itself. This has never, to my knowledge, been a consideration in the design and development of the fab@home technology.

Edited 3 time(s). Last edit at 05/23/2008 09:41AM by Forrest Higgs.

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Thats Kinda funny considering both projects are open source. Microsoft and Mac have the problem of being competitors were RepRap and Fab@home have the advantage of being open source projects that share technology. Not sharing technology really seems kinda pointless.

But if we all worked on the same thing, wouldn't it be dull? The fact that therer are several different projects with different people working on them and different goals is a good thing. It's part of the strength of open source; ultimately we can all learn from other people's work. The ability to share technology is already there... there's nothing to stop fab@home using our thermoplastic extruder for example, nor us their silicone extruder. It just isn't interesting or useful enough to do so right now!

More importantly, people work on their chosen project because they like it, and they can just about get on with the associated community. You can't just stick two projects together and hope it all works out.

And besides, we can make stuff like the skeletons of other repraps, and shoes and coathooks. Ultimately, that's much cooler than ipod cases and watch straps, in my humble opinion

There's certainly some crosstalk between the two. I've noticed ideas from one being incorporated into the other, especially in print head design. I think I saw where someone was working on fitting a RepRap extruder head onto a Fab@Home machine. Given the similar nature of the projects, it's not surprising to see some hybridization.

There are certain differences, though. At the moment, Fab@Home is robust and stable but not very flexible. The current incarnation of RepRap, on the other hand, is still pretty fragile but evolving rapidly. It'll be interesting to see which "breeding strategy" works better in the long run.

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It'll be interesting to see which "breeding strategy" works better in the long run.

Speaking as someone who was all geared up to try making a fabber@home before finding this place, I'd say that reprap being a fraction of the cost is a major differentiator

Yup, Cheaper is gooder.

RepRap is designed to keep getting cheaper as each generation becomes capable of making more of it's parts (my guess is PCB's are next) and as owners of existing machines give away parts to folks who want to build machines (Protocol calls for giving away 2 once you reach production). It is unlikely that Fab@Home machines will get any cheaper anytime soon and may even increase in cost as capabilities are added. Reprap is currently the cheapest 3D printer on the market by almost an order of magnitude relative to a Fab@ kit (vs. the complete kit from Bits & Bytes) and another order of magnitude cheaper than anything commercial.

The difference between Fab@ and RepRap in terms of robustness vs versatility is interesting and probably says a lot about the modes of the two projects. Fab@ was released as a completed project after a period of concentrated work by a few people; RepRap has been evolving in the open since before the first extruder ran.

Also for S&G's a quote from the Fab@ FAQ page:
"How does Fab@Home differ from RepRap?

There are two main differences. The first is that the RepRap is oriented toward self-replication - trying to make a machine that can make many of its own parts, while Fab@Home is aiming to get as many people as possible to play with/hack/improve fabbers. The second is that RepRap has a screw extrusion deposition tool that is designed for use with polycaprolactone plastic as the intended building material, while Fab@Home uses a syringe tool that allows you to use a wider variety of materials.

The RepRap requires a bit more technical proficiency and quite a bit more in terms of the tools you need. For instance, with RepRap, you need need to build the circuit boards and need metalworking machinery to make some of the parts, while Fab@Home is a snap-and-screw-together kit, with bit of soldering as the most challenging part. Of course the RepRap is cheaper for this same reason.

The two projects have a lot to offer each other - you could easily mount the deposition tool from one onto the other - e.g. polycaprolactone screw extruder on Fab@Home or syringe tool on the RepRap Darwin. "

> The two projects have a lot to offer each other -
> you could easily mount the deposition tool from
> one onto the other - e.g. polycaprolactone screw
> extruder on Fab@Home or syringe tool on the RepRap
> Darwin. "

I think that the earlier part of your post pretty much outlined why this really isn't so, at least from the reprap side. Reprappers are low cost folks. Adopting some part of a fab@home printer would be a little like trying to hack pieces of a Mac onto a PC. You could do it, but it would be both expensive and pointless. Better to simply design a syringe for the reprap and print it out.

BTW, the Mk II extruder has successfully printed four plastics so far, PCL (your polycaprolactone), ABS, PLA and HDPE. If I didn't know better, Brian, I would guess that you got what you know about Reprap's capabilities from the fab@home website. That stuff is over a year out-of-date.

Edited 1 time(s). Last edit at 05/25/2008 11:31AM by Forrest Higgs.

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a little like trying to hack pieces of a Mac onto a PC

Nowadays, the underlying hardware is pretty much identical You pay a premium for a pretty exterior. Not that I have anything against that, of course.

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I didn't know better, Brian, I would guess that you got what you know about Reprap's capabilities from the fab@home website.

It looked like a quotation of their site to me, especially as he said as much

But their whole 'wider range of materials' seems pretty disingenuous to me. Fab@home can print lots of stuff, but it basically boils down to 3 types: useful goop (silicone), frivolous goop (cheese), and crunchy stuff (plaster). They can usefully print air hardening silicone, conductive silicone and (allegedly) gypsum plaster. I say allegedly, as actual evidence of successful prints with plaster sees to be tricky to track down.

Their main benefit is a more precisely machined cartesian robot. Getting to a similar level of precision using reprapped support elements and steel spars will be tricky.

So... has anyone played with the reprap goop deposition tool yet, or is it still just a work in progress?

Ru Wrote:
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>You pay a premium for a pretty exterior.

Precisely my point.

> Their main benefit is a more precisely machined
> cartesian robot. Getting to a similar level of
> precision using reprapped support elements and
> steel spars will be tricky.

Now that Nop has got the surface treatment and warping problem under control I suspect that Darwin will be doing that job well, too, especially since Nop is also printing up parts for his own Darwin as we speak.

> So... has anyone played with the reprap goop
> deposition tool yet, or is it still just a work in
> progress?

Adrian designed one and printed it up. I don't know that he's done a lot of work with it yet, though. I think that he's thinking that that can wait for the second generation Mendel printer.

For myself, I intend to use the same plastic as I'm printing with printed more sparsely and at a lower temperature as a support material strategy. That's more or less what Stratasys does, I hear.

Edited 2 time(s). Last edit at 05/25/2008 01:52PM by Forrest Higgs.

>useful goop (silicone), frivolous goop (cheese), and crunchy stuff (plaster).

I think they have an epoxy which looks very useful. It would be good to have a thermoset in our portfolio.

>Getting to a similar level of precision using reprapped support elements and steel spars will be tricky.

Ed's design is clever in that it does not need precise parts to achieve precise results. It has yet to be proved of course, but I don't think the child Darwin that Vik is making will produce parts any less accurate than its parent, being made by a commercial RP machine, does.

---

[www.hydraraptor.blogspot.com]

[fabathome.org]
Link to photo from Fab At Home's site. i think they missed the boat on this one; the two syringes should feed to a single nozzle, so they can dispense 2 epoxy components.

I like how they have the Cornell University logo and Cornell University etched on the clear plastic structure of fab@home.

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the two syringes should feed to a single nozzle, so they can dispense 2 epoxy components.

This sounds like it brings up its own problems... how do you prevent mixed epoxy curing in the dispenser? I guess disposeable nozzles woul dbe essential, although perhaps having a cleaning needle that get spoked up the dispenser tube at the end, or a third fluid source to flush it out might do.

I've only ever worked with resiny stuff I've mixed by hand, so my grasp of the technical problems with this is 'hazy' at best

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Ed's design is clever in that it does not need precise parts to achieve precise results. It has yet to be proved of course, but I don't think the child Darwin that Vik is making will produce parts any less accurate than its parent, being made by a commercial RP machine, does.

I was thinking more of the degree of precision, rather than repeatable accuracy. Being able to blast out a corner bracket, to within 1mm of designed dimensions over a few generations of repraps is one thing, but being able to, say, deposit solder paste for an SMT board terminals is another.

Or so I assume. Feel free to correct me.

HI all

Personally I think the fab@home frame is far better than any of the reprap units... and the heating up of plastics on the reprap is far better than a syringe ... any day... dam shame both are not combined with each others clear advantages... I think the new reprap mondo (uber large version of mendel looks like crap but the print area is 12" (305mm) x 18" (460mm) x 11" (280mm)... nice!!!.. the one concern is how rigid the frame is, how accurate it is is anyones guess the details are not there to prove its worth ...at the moment..

My 2 cents