I am wondering if there is a specific reason and rack and pinion type drive (nylon) would not be better/cheaper/easier than all the belts and pulleys currently in use on mendel ? For example mcmaster 57655K63 . I was just thinking maybe I was overlooking something obvious. https://reprap.org/forum/read.php?1,33645,33645#msg-33645 Sat, 18 Jul 2026 08:06:27 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,33645,36965#msg-36965 https://reprap.org/forum/read.php?1,33645,36965#msg-36965 Forrest Higgs General Mon, 22 Feb 2010 14:32:49 -0500 https://reprap.org/forum/read.php?1,33645,36964#msg-36964 https://reprap.org/forum/read.php?1,33645,36964#msg-36964 bobt General Mon, 22 Feb 2010 14:25:20 -0500 https://reprap.org/forum/read.php?1,33645,36959#msg-36959 https://reprap.org/forum/read.php?1,33645,36959#msg-36959
The low-backlash you report from your printable herringbone gears is great news!

Given that, it may be possible to use printable rack/pinion for milling.
Just as a thought experiment, assume that we could use either microstepping, or additional gear pairs to get small motions, even if the final drive gears had big teeth. (Big teeth presumed for the final "moving the table" stage for strength to resist milling forces without permanent deformations.) I think coarse herring-bone gears might work reasonably well for a mill -- and even if the gears had shorter lifetimes compared to steel or bronze, one could print out spare set(s) while the gears were still in pretty good shape.

Here's something a bit more blue sky, I'm also thinking about how to print (or otherwise make with home-buldable tools), linear bearing stages (like trapezoid ways) that can take the forces of light machining (e.g. Aluminum.) It may be that for those, one is better off milling a pattern into foam, and casting something into it, perhaps epoxy-concrete, with metal bearing surfaces, such as sintered (oil impreganated) bronze.]]> Larry_Pfeffer General Mon, 22 Feb 2010 14:02:00 -0500 https://reprap.org/forum/read.php?1,33645,36934#msg-36934 https://reprap.org/forum/read.php?1,33645,36934#msg-36934 -------------------------------------------------------
> Forrest,
>
> First off, please forgive me for not following
> your work on printable rack and pinion drive
> systems more closely. What software is needed to
> run your rack and gear scripts?
>

You need the open source, free Art of Illusion 3D modeling app. You dump the scripts in the...

C:\Program Files\ArtOfIllusion\Scripts\Tools

...folder and then access them through the scripts option on AoI.


> Have you made any measurement of the backlash, due
> to the rack/pinion themselves? (That is, the
> back/forth motion possible when the pinion is not
> permitted to rotate. I realize that this will
> also be a function of the slop in the linear
> slideways.) Backlash becomes very important for
> milling, something I think will become important
> for speeding up the building of large parts.
> (Extrude faster, using a larger extrusion orifice,
> and then mill off the blobs that ooze outside the
> desired profile, once per layer.)
>
Herringbone gears have very little backlash. The slight printing imperfections in the ones I've printed seem to indicate that there is zero backlash. I've not made formal measurements, mind. Because the gears are plastic, I would not recommend them for use if you are planning to do milling. CNC milling generates significant xy stresses which, I'd guess, makes printed plastic racks and gears problematic.

> My repStrap currently uses leadscrews, but your
> work really has me convinced that printable
> rack/pinion should replace bought threaded
> driverods for the machines I attempt to print. I
> also find it notably cool that the Herringbone
> gear pattern can be extruded, but would be quite
> difficult to make using a conventional mill -- or
> even a hobbing machine (at least the ones I've
> actually seen outside of books.)

yeah, additive printing can do things that are difficult or impossible with subtractive CNC milling. I have come to the conclusion that we've got to stop thinking of our printers as just a poor man's CNC machine and start finding design solutions that exploit their strengths.]]> Forrest Higgs General Mon, 22 Feb 2010 11:21:18 -0500 https://reprap.org/forum/read.php?1,33645,36660#msg-36660 https://reprap.org/forum/read.php?1,33645,36660#msg-36660
First off, please forgive me for not following your work on printable rack and pinion drive systems more closely. What software is needed to run your rack and gear scripts?

Have you made any measurement of the backlash, due to the rack/pinion themselves? (That is, the back/forth motion possible when the pinion is not permitted to rotate. I realize that this will also be a function of the slop in the linear slideways.) Backlash becomes very important for milling, something I think will become important for speeding up the building of large parts. (Extrude faster, using a larger extrusion orifice, and then mill off the blobs that ooze outside the desired profile, once per layer.)

My repStrap currently uses leadscrews, but your work really has me convinced that printable rack/pinion should replace bought threaded driverods for the machines I attempt to print. I also find it notably cool that the Herringbone gear pattern can be extruded, but would be quite difficult to make using a conventional mill -- or even a hobbing machine (at least the ones I've actually seen outside of books.)]]> Larry_Pfeffer General Fri, 19 Feb 2010 16:28:56 -0500 https://reprap.org/forum/read.php?1,33645,36297#msg-36297 https://reprap.org/forum/read.php?1,33645,36297#msg-36297 -------------------------------------------------------
> Forest,
>
> Have you released your rack and pinion script yet?
> I'd like to see if I can print it and show off
> the parts to some people I'll see this weekend.


You are, of course, welcome to them. The rack script is clean. The pinion script has a glitch which causes a flaw in the gear which doesn't affect the mesh surface. I haven't had time to chase down how that flaw is happening, but discovered that I could repair it with the free Netfabb download.

Alternatively, I could simply generate a rack and pinion, clean up the pinion and ship those to you, if that is more appealing. I'm attaching the scripts to this forum message. If you want the other, send me a private message. You will probably want bigger ones than I have been printing with my 0.3 mm extruder head.]]> Forrest Higgs General Tue, 16 Feb 2010 10:53:11 -0500 https://reprap.org/forum/read.php?1,33645,36294#msg-36294 https://reprap.org/forum/read.php?1,33645,36294#msg-36294 -------------------------------------------------------
> So getting back to the whole printed rack and
> pinion idea. The problem with rack and pinion is
> that we have to move the relatively massy y axis
> stepper motor with the X axis.

So? You already do that with both Darwin and Mendel. It is the same with Darwin and with Mendel the z-axis raises and lowers the x-axis..]]> Forrest Higgs General Tue, 16 Feb 2010 10:41:54 -0500 https://reprap.org/forum/read.php?1,33645,36244#msg-36244 https://reprap.org/forum/read.php?1,33645,36244#msg-36244
It's also hard to do a conveyor belt part ejector on a moving bed.

I see no reason for using rack and pinion on the z-axis, unless we come up with some weird locking mechanism.]]> Gene Hacker General Tue, 16 Feb 2010 01:14:39 -0500 https://reprap.org/forum/read.php?1,33645,36243#msg-36243 https://reprap.org/forum/read.php?1,33645,36243#msg-36243 Corwin General Tue, 16 Feb 2010 00:58:21 -0500 https://reprap.org/forum/read.php?1,33645,36241#msg-36241 https://reprap.org/forum/read.php?1,33645,36241#msg-36241
Also I'm worried that the printed rack and pinion may not be accurate enough to make itself. Though if worst comes to worst it might be possible to 'grind' racks and pinions.]]> Gene Hacker General Tue, 16 Feb 2010 00:17:48 -0500 https://reprap.org/forum/read.php?1,33645,36188#msg-36188 https://reprap.org/forum/read.php?1,33645,36188#msg-36188 Personally, I wouldn't screw it to pegboard. Dimensional stability of pegboard isn't up to much. If it were me, I'd glue it to float glass. That stuff is cheap and for practical purposes optically flat.

How about optically flat polymer concrete with 1" regularly spaced holes?
[objects.reprap.org]

But prototyping on masonite (or steel) pegboard. Or erector set. Or anything else with regularly spaced throughholes.

---

BeagleFury, I'll get back to your queries when I've got a moment. Or you can bring them up in the Library Admin Forum.]]> SebastienBailard General Mon, 15 Feb 2010 14:27:43 -0500 https://reprap.org/forum/read.php?1,33645,36168#msg-36168 https://reprap.org/forum/read.php?1,33645,36168#msg-36168
Have you released your rack and pinion script yet? I'd like to see if I can print it and show off the parts to some people I'll see this weekend.]]> mccoyn General Mon, 15 Feb 2010 11:06:59 -0500 https://reprap.org/forum/read.php?1,33645,36164#msg-36164 https://reprap.org/forum/read.php?1,33645,36164#msg-36164
>> *Is there a release schedule, no.
>> *Is there a target features release system, no.

A release schedule looking forward 1 or 2 years would be nice, but not necessary. What this provides to new or semi-new people is an idea for whether waiting for higher availability and better printing capability would be worth it, vs. simply jumping into the fray now, based on that individual's level of frustration tolerance or ability. When will the next version of official reprap (Darwin, Mendel, ...) machine be in 'beta'? I realize a lot of this cannot be predicted, and commiting to meeting a deadline challenging when rewards consist entirely of non-financial payment.

>> *Is there community infrastructure to have a benevolent dictator accept or reject patches, no.
>> *Is there a community infrastructure to vote to accept or reject "patches", no

The advantage to this becomes one of consistency. If you have one person or tight group acting as gateway to allow new features or fork merges back into the official release, you get that person's or group's vision for what RepRap represents. Having the swarm mentality, you get a bit more churn in the mix, but vastly more innovation. Advantages either way; disagreements about this as important seem to stem simply to which priority takes precedence: ease and simplicity vs. innovation and power.

>> *Is there any articulation or documentation of the professional and financial conflicts of interest among principal participants, no
>> *A lot of things are under licenses which really can't be applied to them, such as applying the GPL to things which aren't source code or compiled source binaries. There are pretty compelling legal reasons why the GFDL and the CC license exist, they were created to address coverage of articles that are not computer programs.
>> *There are huge patent, trademark and copyright issues with most of the solutions being explored here.

I feel this also is a large sore point. Given the lack of information about what "hardware" GPL means, especially considering that the FSF and Richard Stallman have stated that "GPL applied to hardware" is nonsense at this point in time. I have yet to see an answer that discusses the rights granted to the non-software components within the RepRap heirarchy. I'm less interested in the financial conflicts of interest; as it stands, making the hardware rights made known should be adequate for either commercial or non-commercial use of *ALL* the components (software and hardware) of "RepRap".

>> *Are their any clearly articulated goals for the current release, not that I could find. --There IS the general "RepRap is a free desktop 3d printer capable of printing plastic objects. Since a large part of the RepRap is made of this same plastic the RepRap can be considered a self-replicating machine - one that anyone can build given time and materials." Which is fine but extremely ambiguous, even two 'official' contributors (nophead and sebastian) seem to have mutually exclusive interpretations.--

This is one point on which I disagree. The goals may be somewhat open ended, but the reprap website home page fairly clearly states the goal of producing a low cost self-reproducing desktop manufacturing machine. To quote: "The primary goal of the RepRap project is to create and to give away a makes-useful-stuff machine that, among other things, allows its owner cheaply and easily to make another such machine for someone else."

>> *Is there any tracking or response infrastructure for resolving bugs/glitches, no (I don't count a wiki page).

This would be nice; Sebastian, how hard would it be to add one of the several bug tracking systems into the reprap site with home page "http://bugs.reprap.org" or something like that? Is there already something like this set up?

>> *Competing projects are drawing more attention and brain power (makerbot, cupcake, contraptor, 3dp, etc).

I feel this is a mixed bag. In one sense, it's good because it gets greater visibility to the idea that cheap 3D is fun and inexpensive. However, I've also seen a bit of press on RepRap too; I think it's all about having a 'front-man' who's sole contribution is in marketing and promotion; this can be tricky to find when the rewards are non-financial.

>> *I and the people I try to bring on to the project are immediately dead-ended on the bootstrapping issues, #1 most frequent advice is to send people to a competing project (cupcake). To me this is like ubuntu saying, ok to install our system please first install redhat...

This is key. I wanted an official "Mendel" version of a RepRap machine myself. The current model is near impossible for a semi-novice, semi-tech capible person to build without access to a pre-existing 3D printer for nominal cost above one with RP available. If I had available a 3D printer, I suspect I would have had a Mendel up and running for about US$800. As it is, I have a few wooden parts that I've been able to make, and a $600 pile of parts. I do feel this may be a short term problem, but it is one very keenly felt at the present; it is not a valid option, in my opinion, to double or triple the funds needed up front, even if some of that cost can be recouped later (E.G, the "buy a millstrap", or "buy a MakerBot", or "buy a RapMan".) I want a Mendel. If I wanted a millstrap or a makerbot or a rapman, I'd probably be a much happier person right now.

In my vision, a RepStrap version of the official line should be almost as easy to make without a 3D printer as the second generation version; this has been my goal with RepolaRap; So far, I still think I can attain this goal; with $100 in tools, $100 materials, and $200 in electronics, I've made a working and fast X+Y axis structure. I estimate the Z axis structure and extruder will be another $400 at most, so overall cost competes quite well with Mendel. The biggest problems facing me have been software/firmware related; I've probably spent 3x to 5x more effort getting the software going than the hardware. This is a very good thing, because leveraging that effort to copy a bit of software is vastly more simple and easy than copying a bit of hardware, if you assume you have a computer and internet, but no 3D printer. I realize this still doesn't get me a Mendel, but as I'm using that $600 part bin in the corner, the extra material costs actually come in at less than $100, so, if I or someone else who's made a RepolaRap wants, the can use it to print out all the Mendal parts, then scavange all the motors and electronics off it to make the Mendel. Final investment over and above the cost of Mendel: $100. Final time investment assuming you have the software, a weekend or three. I believe others will find this appealing; I certainly would have. (I am aware of McWire; from what I've heard and seen, it is very slow.)

>> *Is there a defined process (proposal guidelines, patches guidelines, anything,,,) for contributing other than "add it to the wiki", no

Sebastian, is there a wiki page for how to add images, content, source code, board designs, etc. to the wiki, and recommendations to maintain some consistency for how content is managed and layed out? If not, it seems it should be pretty straightforward to create one based on the steps you usually use when you create a page for others, and add a "How to create content for this wiki" as one of the first items in a FAQ and menu item or something like that? And by this, I don't mean a link to a template, but rather, use case flow oriented: Step 1, click here and type the name. Step 2, add a summary section. Step 3, click the "add image" button to add images, (etc.)]]> BeagleFury General Mon, 15 Feb 2010 08:57:56 -0500 https://reprap.org/forum/read.php?1,33645,36163#msg-36163 https://reprap.org/forum/read.php?1,33645,36163#msg-36163 -------------------------------------------------------
> And most importantly, Rack and Pinion needs to
> improve.
>
> Forrest, what's the longest summed Rack you've
> made?

I printed one that I think was 220 mm long. That is the diagonal length of my Rapman print table less a little bit for width and raft.

> And is it easy to bolt to pegboard?

The script to build the rack is a hairy little piece of java. I extended the rack with flanges on either side of the rack in the script.

As to tacking it to anything, you need to design a connector that mates with the rack. I designed a column system that slots pieces of rack...

[technocraticanarchist.blogspot.com]

... for my Delta 'bot pick and place project.

Personally, I wouldn't screw it to pegboard. Dimensional stability of pegboard isn't up to much. If it were me, I'd glue it to float glass. That stuff is cheap and for practical purposes optically flat.]]> Forrest Higgs General Mon, 15 Feb 2010 08:48:33 -0500 https://reprap.org/forum/read.php?1,33645,36149#msg-36149 https://reprap.org/forum/read.php?1,33645,36149#msg-36149
Forrest, what's the longest summed Rack you've made? And is it easy to bolt to pegboard?]]> SebastienBailard General Mon, 15 Feb 2010 04:27:07 -0500 https://reprap.org/forum/read.php?1,33645,36145#msg-36145 https://reprap.org/forum/read.php?1,33645,36145#msg-36145
Warning - it is after 3 AM where I live. I will disavow anything
I've typed here until I've had a chance to sleep on it. As opposed to
usual, when I just blame the cat for things I wish I hadn't
written. Anyway, this is an utter ramble.

---

Documentation needs to improve.

But we do need bugtracking, and I assert that we need to build social
networking into the wiki so that people get feedback (praise,
favoriting) when they upload to it. Right now the wiki, she is an
emotional black hole.*

We've got an extruded aluminum RepStrap candidate:
[objects.reprap.org]

But sam's not going to want to upload without social networking-type
"Nice job", and "800 people favorited this post", etc.

I agree that "1 team" is silly. But regarding "COORDINATED TEAM". We
need COORDINATED TEAMs. 1024 of them. Like the Heated Bed team, the
SpoolHead team, the skunkworked SDM team, and the new extruded
aluminum team.

Being able to offer email will help. So will having the wiki do all
the user comms for some teams via shoutboxes.

---

Distribution needs to improve. e.g. a "tender" system for Mendels,
etc.

---

I think that debian does do dedicated subteams very well. (It's been a
while since I lurked over there.)

Although I think we mostly want swarms.

The linux and linux kernel analogy some people invoke, "adrian ?=
linus" is an utterly wrong analogy. Because we have stacks, or machine
configurations which are RepRaps without using any element from
mendel. But they may still be utterly cool.

(I think the extruder is the kernel. Unless ... it's the slicer?)

I think Adrian is the Debian Project, maybe?

---

quasi-self-replication can be a more realistic and desirable feature
for pre-nano RepRaps. Like a RepRappable lathe, and a dedicated
extruded aluminum pick and place, and so on, all of them open source
and in the wiki, capable of donating features and parts to post-mendel
candidates, and also obeying the "Everything in One Place" scenario.
[objects.reprap.org]

---

*On generic wikipedia, that is done via the "discussion" tab. But that
separated wikipedia into two populations. And that won't work for
RepRap.]]> SebastienBailard General Mon, 15 Feb 2010 03:25:00 -0500 https://reprap.org/forum/read.php?1,33645,36137#msg-36137 https://reprap.org/forum/read.php?1,33645,36137#msg-36137 -------------------------------------------------------

Kevin,

You can take offense and get upset and preach and complain and threaten till the cows come home. It will make no difference whatsoever to the Reprap project. With Reprap, your worth and reputation are dependent on what you do, not what you say and especially not what you demand. If you look at the people who are highly respected you'll find that they are the guys like, inter alia, Vik and Nophead and Zach. They put their passion and energy into making Reprap happen and have been for years. That's how you gain stature in an open source project, pure sweat equity. You don't just walk in off the street and start making pronouncements and expect to get paid much attention to. You solve a problem that advances the state of the art and people start noticing you fast.

I'm probably the "certain people" you so coyly refer to. I'm a big boy. You can call me by name. I don't mind. I call 'em like I see 'em.

"I know a thing or two about running projects and creating an environment of innovation..."

So do I. I've been a senior scientist, team leader, project manager and the like at universities, gov't labs and corporations for onwards of thirty years now. I've worked research and development teams in strongly hierarchical management structures, flat management models and unfunded quasi anarchies like Reprap. I've been damned good at it.

Problem is that in all of my non-Reprap experience, I could motivate team members with money, respect and advancement. You suggest that...

"..if I had the means I would organize a team of 5-7 key people with expertise in key areas who have worked on this project to work together for couple of years to create the machine we all dream about. Unfortunately I don't have the time\means to do it today...BUT I THINK THIS IS THE ONLY WAY THIS CAN ALL BE EFFECTIVELY MANAGED. IT IS A FULL TIME JOB FOR A DEDICATED AND COORDINATED TEAM {emphasis mine}."

That's just great. Basically, what you've said that is that the only way to make Reprap succeed is with a conventional R&D team. You even have the chutzpah to say that...

"I have never laid eyes on a RepRap in person, much less made one"

Conventional R&D teams got 3D printers down to a cost of about $50,000 in 2005 when we began with Reprap. It took conventional R&D teams about fifteen years to get the state of the art to that point.

It cost about $30/cubic inch to print things with one of those machines. In the five years since then our anarchistic, uncoordinated, and in your opinion doomed to failure effort has reduced the cost of 3D printers to well under $1000 and the cost of printing to about 15 cents/cubic inch. In the same time, conventional R&D has managed to reduce the cost of printers to about $15,000. I can't but wonder whether they would have moved nearly so fast if they hadn't had the wolves of Reprap snapping at their heels while passing them.

If that's failure, I don't know about you, but I could do with a lot more of it.

People are here because they want to be here. They aren't paid. They're doing what they're doing for the pure love of it. The core team is here because early on they were captivated by Adrian Bowyer's vision of a future with virally diffusing technology where the scaling of manufacturing endeavours drops by several magnitudes. They want ordinary people to be able to design and make things. They don't believe that the future belongs to a priesthood of "DEDICATED AND COORDINATED TEAM(s)".

Even as hopelessly retro a publication as Wired has finally caught on. Their lead story this month is "The New Industrial Revolution". LOL! It took them five years to catch on, but they finally did.

It's the 21st century. The aptly self-named goinginreverse is hopelessly committed to the 19th-20th century notion that mass production is the only way to do things. You're similarly committed to 20th century R&D model for technical innovation. Both notions are living on borrowed time.

These days it's OODA loops, Swarming and Crowd Sourcing. Like it or not, that's what is happening in Reprap. We're solidly 21st century.

Forrest]]> Forrest Higgs General Mon, 15 Feb 2010 01:27:24 -0500 https://reprap.org/forum/read.php?1,33645,36130#msg-36130 https://reprap.org/forum/read.php?1,33645,36130#msg-36130 I already had a go at that page. I added the verbiage around the t-slot RepRap version...

I just had a go at it myself.

It occurs to me that t-slot seems purpose made for us to slip RepRap-made Herringbone Rack into it ...]]> SebastienBailard General Mon, 15 Feb 2010 00:05:04 -0500 https://reprap.org/forum/read.php?1,33645,36123#msg-36123 https://reprap.org/forum/read.php?1,33645,36123#msg-36123 maitri982 General Sun, 14 Feb 2010 22:33:30 -0500 https://reprap.org/forum/read.php?1,33645,36122#msg-36122 https://reprap.org/forum/read.php?1,33645,36122#msg-36122 [objects.reprap.org]
or
[objects.reprap.org]

Also note that we're running into the fact that RepRap is a constellation of different technologies which we mix and match when we build a particular instantiation. Like bolt a ceramic extruder onto a bridgeport mill.
[objects.reprap.org]

---

Now that we're done with that derail, is your machine going to use belt, or rack?

I've been thinking about extended bed machines which use belt or rack to move 4 feet of bed back and forth, but on a mendel with a footprint of 1-2 feet. We might want outriggers to support that. Or lay rails on our basement or workbench floor. :)]]> SebastienBailard General Sun, 14 Feb 2010 22:08:19 -0500 https://reprap.org/forum/read.php?1,33645,36119#msg-36119 https://reprap.org/forum/read.php?1,33645,36119#msg-36119
There should be a certain sense of decorum between people on such projects. My experience is that friction of ideas fosters the creative process, but only amongst mature individuals. if it degrades to insults or calling something "bitching", then this means that the core team is really not in favor of progress as much as protecting their "baby" from constructive criticism.

This is too bad because I think that goinreverse wants very much for this project to be successful, and his points are all valid. I have never laid eyes on a RepRap in person, much less made one, but I know a thing or two about running projects and creating an environment of innovation...and frankly this project is a mess. This is not to blame anyone, because it is no ones fault. It is due to the fact that doing 3D printing is so new and there are so many tangents that can and will be explored by all the smart people here, that it is hard to manage.

there are probably 4-5 core skill sets involved in 3D printing including electronics, materials sciences. software, and mechanical design, and it is clear that each of these areas has extreme innovation going on separately. So managing this without a strong coordinated effort is VERY hard, if not impossible.

if I had the means I would organize a team of 5-7 key people with expertise in key areas who have worked on this project to work together for couple of years to create the machine we all dream about. Unfortunately I don't have the time\means to do it today...but I think this is the only way this can all be effectively managed. it is a full time job for a dedicated and coordinated team.

Perhaps it takes commercial interest to look at all the things being developed by various parties and to then integrate that into a great design, ala MakerBot, and that is fine with me. My hope is that a 3D printing machine is created that we can all have that can produce many everyday devices such that the cost of the device is less than the products it will produce. For me I could care less whether it self replicates...cool if it can, but not really essential IMO. If it is cheap enough then self replication really is irrelevant.

Kevin]]> maitri982 General Sun, 14 Feb 2010 21:17:34 -0500 https://reprap.org/forum/read.php?1,33645,36099#msg-36099 https://reprap.org/forum/read.php?1,33645,36099#msg-36099 Triffid_Hunter General Sun, 14 Feb 2010 15:34:02 -0500 https://reprap.org/forum/read.php?1,33645,36089#msg-36089 https://reprap.org/forum/read.php?1,33645,36089#msg-36089 -------------------------------------------------------
> Forrest, I posted recently about how I heatsinked
> my A4983s. method works really well! Note that the
> Vbb (Vmotor) capacitors and the current pot are
> taller than the chip, and some of the other smt
> parts are very close to the same height as the
> chip so a shim or riser is highly recommended

Triffid: I'm assuming that you are talking about this...

[picasaweb.google.com]

where you park a fan over the breakout boards?

If so, that's good. I salvaged a fan a few months ago that is just the right size from a PS2 that my son wrecked years ago.]]> Forrest Higgs General Sun, 14 Feb 2010 11:31:25 -0500 https://reprap.org/forum/read.php?1,33645,36079#msg-36079 https://reprap.org/forum/read.php?1,33645,36079#msg-36079 I particularly like the use of
> plain paper, adhesive and a cutter that creates
> wood-like objects at a very low cost - the main
> cost being the special adhesive required. Others
> use a roll of plastic, adhesive and a cutter which
> makes even stronger parts but at a significantly
> higher cost (plastic vs plain 80/160 g paper).

I agree. I admire the mcor technologies machine, but it's still pricing itself out of the market, at between 20K and 25K euro. I've been daydreaming about a Mendel bed without Z axis, just pen up and down like a plotter, with say five y axes, each carrying, instead of knives, dentists' drill air motors that have 1.5mm burrs that rout slots in a sheet of paper instead of cutting with a knife. With multiple Y axes, the x travel only has to be 60mm with the y axes varying their rate and lifting and dropping. Dentists' drills have a free running speed of up to 500,000 rpm and I don't think that sharp burrs slotting a sheet of paper will slow them much. They're compact, so lifting and dropping, they only need about 100mm of headroom, so the Mendel beds could be stacked to run multiple sheets simultaneously. Adrian's experiments have shown that at least four repraps can be run from USB on a laptop, so coordinating the operations would be slightly more complex than that, but less so than, say, a five axis milling centre. Each sheet of paper is a .1mm layer, but if you're building a small model, say a 50mm square footprint, each sheet could give twenty or more layers, 2mm thickness, with the same sort of speed as a reasonably quick printer. If the burrs cut two holes for register in each slice, they could be manually stripped and stacked on posts quite quickly, then drenched in cyano and sprayed with accelerator to set them instantly. I think that surface finish would be more consistent than extruded plastic. Prototyping value only, but truly rapid. Multiple beds could be stacked vertically to increase speed by multiples. Cheap and fast. Just a thought.]]> murd General Sun, 14 Feb 2010 07:07:13 -0500 https://reprap.org/forum/read.php?1,33645,36078#msg-36078 https://reprap.org/forum/read.php?1,33645,36078#msg-36078 Triffid_Hunter General Sun, 14 Feb 2010 06:01:53 -0500 https://reprap.org/forum/read.php?1,33645,36058#msg-36058 https://reprap.org/forum/read.php?1,33645,36058#msg-36058 -------------------------------------------------------
>
>
> Forrest, what's new with you and Rack and Pinion?
>
I got Herringbone Rack and Pinion working and got a mounting beam that the rack can integrate into designed and tested to an extent.
>
> Also, have you tried testing it to destruction
> with an automated test rig, say, moving a 5kg
> weight back and forth 10,000 times?
>
I have something like that in mind. I found that Pololu have Allegro A4983 breakout boards which get you microstepping down to 1/16x. I took delivery on those a few days ago, but have been ill this week so haven't had a chance to get them running with my I2C MCU. It doesn't look like any big deal to hook up and test. The only rather scary part is that the A4983 chip is supposed to handle 2 amps. The problem with that is that it is about as big as a sequin, viz, a 4-5 mm square, surface mounted chip with connectors you need a microscope to see. It's going to be tricky putting a heat sink on that puppy. Once I get the driver board working with the NEMA-17 setting up a test rig to see how accurate and repeatable the positioning is and how it wears will be happening.

Fortunately, that breakout board lets me directly drive the rack and pinion instead of going through reduction gears. That makes it both simpler and probably more reliable.

Right this minute, I'm recommissioning Slice and Dice, the pixel-based STL slicing approach that Adrian used to hate and then decided that he loved a month or so ago for the Rapman printer that I own. I ran into problems making gcode out of the light, openwork structures that I have been working with lately when I use Skeinforge. Doing that sort of thing really tests Skeinforge's performance envelope, so I'm reviving my own code. That lets me dive into the code rather than having to ask other, busy people when things go wrong for me.]]> Forrest Higgs General Sat, 13 Feb 2010 22:59:32 -0500 https://reprap.org/forum/read.php?1,33645,36056#msg-36056 https://reprap.org/forum/read.php?1,33645,36056#msg-36056 Figuring out what should and should not be covered in the wiki,

I don't understand what "should not be covered" in the wiki, aside from handguns. I'd take wiki-deletionist arguments more seriously if they were presented by people uploading parts and text into the wiki. "should not be covered" really means: needs to be documented in a more careful manner if new user-developers are actually getting confused.

And frankly, if Person A is telling Person B that "your stuff doesn't belong in the wiki", then I'm going to get angry with Person A, because it's my job to help Person B get their RepStrap, RepRap, or new extruder, laser, etc up there. Unless we think that McWire and Mendel are perfect, and we are done. :)-D

If Person A feels that strongly about it, they should set up their own damn wiki and fiercely protect from icky foreign content and machines. Or go and keep everything in a lab notebook. Or, more likely, blog the hell out of it and upload every damn thing they make to thingiverse, while not uploading any damn thing they make to RepRap, as may or may not be happening right now.
what full releases should be covered,

Presenting and maintaining a "RepRap Stack" of modules that work together is a crucial RepRap developer responsibility. As is documentation. Mind you, I might be working on an [[Eiffel]], [[BitBanger]], Extruder-and-Spindle aka[[SDM]], and [[EMC]] Stack 50% of the time.

This is much easier with the Linux kernel, gnu tool chain, directory structure, X window software, KDE Desktop, and Firefox browser that I'm using right now, aka my "Browser Stack".

But helping maintain the wiki that we use to sort this all out is the responsibility of all of us.

Deleting everything but the current working Sat Feb 13 22:13:21 EST 2010 RepRap Stack is silly.

and how often they should be adjusted for changes to parts/electronics, etc

People who don't want to work on new parts and electronics shouldn't tell the people who do, aka "RepRap Developers" to stop doing research and (hopefully) documentation. But they do have the right to say "this isn't documented, except on your personal blog".

It would be a lot less work for us old hands if we just completely and utterly abandoned each old version in order to just blog our latest research. It is, perhaps, not the most ethical way to go about RepRapping, though though. :)

is something that we should be talking about. In another thread.

Yup. Agreed.

Forrest, what's new with you and Rack and Pinion?

Also, have you tried testing it to destruction with an automated test rig, say, moving a 5kg weight back and forth 10,000 times?]]> SebastienBailard General Sat, 13 Feb 2010 22:23:55 -0500 https://reprap.org/forum/read.php?1,33645,36030#msg-36030 https://reprap.org/forum/read.php?1,33645,36030#msg-36030 Corwin General Sat, 13 Feb 2010 14:39:47 -0500 https://reprap.org/forum/read.php?1,33645,36001#msg-36001 https://reprap.org/forum/read.php?1,33645,36001#msg-36001 Seems an odd line of bullshit to find on a rack and pinion thread.

Well, we're really trying to sort out the RepRap [[Combinatorics Problem]]
[objects.reprap.org]

Hypothetical examples of stuff which is welcome and needed at
RepRap.org, and also issues at play:

The German-speaking Laser Expert is building a self-replicating Laser
Cutter and SLS-RepRap. The documentation is perfect. And in german.

The Russian-speaking New User is annoyed by the Russian langauage
forum because of russian-language pornographic spam that the
english-speaking forum moderator misses.

The Arabic-speaking Guy Who Wants to Translate RepRap into Arabic is
still waiting for me to make a arabic-RUG and initate a
arabic-Wikipage.

The Japanese-speaking Expert built a self-assembling set of
"[[RBS/Blocks]]". The documentation is perfect. And in japanese.

Joe User can't buy Mendel Parts.

New user-developers can't do this unless each step has been
documented. Experienced user-developers would rather research and
develop than document. Entrepreneur user-developers want to sell one
set of Mendel parts, or 50000 sets of electronics, filament, Mendel
vitamins and need RepRap to do documentation and support.

Jack Developer just forked his LaserCut RepStrap. And the RepRap
Development, Documention, and Object Library, and everyone with a
working RepRap now uses the Object Library to document their
post-mendel variants, cause they like to keep all their stuff in one
place. Also because people with working RepRaps don't go back to the
RepRap.org website unless there are interesting Library Object Files
there, unless they are making another RepRap.

A fellow in India makes molds for Mendels with his Mendel. Each mold
set casts 4 mendel plastic parts sets a day.

Please note there is also a "RepRap Service Work Problem", I would
prefer to spend no more than one hour a day doing forum and wiki work
to preserve personal time for play, figurative sculpture, building
Robots, designing new RepRaps and RepStraps, and working on getting my
machines existing, running, and self-replicating. To say nothing of
dreaming up and making new things for the RepRap [[Library]].

People who urge me to spend more than 1 hour a day doing RepRap
Service Work may at any time be urged in turn to either volunteer to
help with Service Work or to "go self-replicate". :)

Also, I need to scan and tidy up my concept drawing for [[LeCorb]], a
Tablesawable FlatPack Repstrap made from pegboard and BlodgeIt's
plastic cabinetmaking widgets. In other words, LeCorb is basically an
Eiffel with lots of RBS/Sheet and 24 tiny segments of RBS/Beam.
LeCorb will be very cheap and easy to make.

After that, I'll scan and tidy up my concept drawing for an Eiffel
PourStrap. Eiffel PourStraps are good SDM machines because they can
also support a spindle. And they should be fairly cheap, materials
wise, compared to generic benchtop mills and benchtop cnc routers.
Along with being (1) cripplingly expensive to ship, and (2) you can
make the molds with things that cut sheet. (3) molds are cheap to ship.

Oh, and I think we'll have formal bugtracking software in place at some point.

And I'm pretty sure Adrian would rather do research than work on more
than 2-3 of the above problems, until we've got the RepRap [[Cloning Vats]]
running, anyway. But I know he's in charge of figuring out all this
stuff. I don't know if he knows that. ... But this is all Adrian's
job to figure out. Really. B)-

---

I'm glad there is so much energy in this forum thread from people
eager to volunteer to help and also people eager to go out there and
self-replicate.]]> SebastienBailard General Sat, 13 Feb 2010 06:26:53 -0500 https://reprap.org/forum/read.php?1,33645,35993#msg-35993 https://reprap.org/forum/read.php?1,33645,35993#msg-35993 -------------------------------------------------------
> I would love to be persuaded to change my mind on that.
>
Has it ever occurred to you that changing your mind just possibly isn't all that high a priority for people in Reprap?]]> Forrest Higgs General Sat, 13 Feb 2010 02:40:50 -0500