My deal.

((note, this post has been sitting in draft status for a little while now. i'm going to try to catch myself up and hopefully soon, start posting about what i'm dealing with in more or less real time.))


This is where we quickly go through the mechanicals and some of the hurdles I've seen and some that I expect.

There's a few ways of getting into the project. The best, and hopefully eventually the easiest way, is to get in with someone or some group who have one up and running. They can print you the parts and you can be on the merry way (though the non-printed portions are still a bit expensive, you'll still save a bunch).

We've haven't hit saturation yet, so it might be a bit hard to get a hold of some reprapped pieces. That's where the concept of repstrap comes in. A reprap is a self-REPlicating RAPid prototyper. a repstrap is a bootstrapped method of making a repstrap, it can't make itself, but it can make parts for a reprap.

There are quite a few ways of doing this. Two common paths include a Mcwire, or a Darwin clone (Darwin is the name for the "standard" community designed reprap, but you knew that if you checked the link I gave in the last post.). Mcwires are a good quick and cheap way of getting a cartesian bot setup up and running. Darwin clones look and feel like a standard reprap, but are generally made of differnet materials. Laser cut acrylic is very common (ponoko or bits from bytes), the original darwin unit was made with cast plastice parts, and some have even successfully cut and carved darwin pieces out of wood.

the benefits of the clones is that you can replace parts as you go, a corner bracket here, a motor mount there. with the mcwire, you can fabricate all of the darwin parts, and then build it up and swap your motors and electronics. right now all use the FDM head, and that would simply be transfered (oh don't worry, people are working on all sorts of fabrication heads and methods, dunno how close they are though.)

oh, and there is also the little and cute Cupcake from Makerbot. basically a small modified mcwire (by what i can tell, moveable stage, though i can't see how the z-axis is implimented.) It's made to use the generation 3 electronics which look real good, but since it is so small and cute it is limited to a 10x10x10cm build volume.

I knew I only wanted to buy one set of the electonics, and only one set of motors so I didn't want an eviscerated mcwire sitting about. Not many reprappers in these parts so no reprapped parts available, and I'm sure that normal demand for parts is through the roof anyway, or at least great enough that the laser cut solutions can charge me $300+ for the privilege. So that's what I went with. Vik on the forums was able to provide a slight discount through Ponoko, which is definitely nice.

Now, when I start building parts I can replace them as I go (or as they break; unfortunately acrylic is fragile and so I have to avoid over tightening, and so it can loosen, and as I re tighten, there's another chance of breaking, etc.) The build instructions aren't identical, but they are similar enough to make it work (as far as I can tell)

As an mechanical engineer, the physical build is where I think I can help the most. Of course one member of the forum, Forrest, is quick to dismiss if he doesn't feel you've put in the time and I'd have to agree, so I quietly decided to hold my cards until I've followed the group and built a working unit. Then I can start pushing out modifications and updates that can maybe simplify or refine issues I feel the design still has. Of course the community doesn't have to follow, but I'll state my case here on this blog and we'll see if the refinements are determined to have merit and are adopted or at least considered in the general design direction. When I first got involved in the project I made some comments on some gaping holes I saw in the heat transfer design of the extruder, and hopefully that helped one of the key engineers, nophead, decide to look into it a bit more with some fantastic experiments and prototypes. Even if my comments just happened to coincide with his efforts, I'm glad I made them. When I have my hapsrap running I'll be right up there with them, testing the state of the art.

yes?

So I've been going back and forth on actually starting this blog. Mostly because I'm not too great with keeping up with this sort of thing, and I do enough documentation and reports while at work. But, here we are. I hope it's informative.

For a while now I've been following along with the concentrated efforts of a great variety of people through the web. The goal for this group is "democratizing manufacturing" or "China on your desktop" or a bunch of other PR slogans people have put together on a bunch of articles and interviews and blah blah blah. I've come to just refer to it as "my nerd project". Others know it as RepRap, or more descriptively it's an open source Fused Deposition Modeling (FDM) 3D rapid prototyper.

The basic premise is this; Wouldn't it be awesome if you could hit print on a 3d model you just downloaded on the web and then have it in your hands later the same day? If you need a custom bracket or brace, why not sketch it up in a free program and then have it built one layer at a time? For pennies.

I'll tell you why I was attracted to it, it is probably similar to why many of the participants spend so much weekend and evening time on it. It's a playground. These machines already exist commercially. They cost thousands of dollars and that puts it out of reach for many many people. Plus making something out of plastic can only be so much fun. It's the building and tweaking and hacking that's the real appeal. The project is open source, and there is a fantastic array of people of all different spheres to help you through with just about any problem (I'll start a list of links sometime soon, I promise). There's been great strides on all aspects of the project; electronics, mechanics, and software, and a lot of different ways to put all of those parts together as a functioning system. Imagine an erector set that is self-expanding.

Now for why I'm starting this blog. I've been doing "hella" research on this project. What's the way I want to get started? What do I need? What do I need to learn? What are going to be my biggest hurdles? After months and months and months of following the forums and trying things out myself, I've got a good idea of what I need to do, so maybe I can share that with other people interested in the project. Eventually, when I do have my hapsrap built and functioning, I'd like to push new "technologies" and methods, bring a little bit of my engineering experience and design some experiments to hopefully help the certainly capable people who already helped me get to that point.

Also I can point my friends and coworkers to this page and they hopefully get a better idea about what this nerd project I keep referring to is about.