Extruder Kit, announced by Zach as "Coming Soon" is now at parts.reprap.org
But nothing about this written at news...

See [forums.reprap.org]

---

[www.hydraraptor.blogspot.com]

What an ugly cheating and discrimination!

Well when demand exceeds supply, serving people who have been waiting the longest is normally considered the most fair way of doing things.

---

[www.hydraraptor.blogspot.com]

I really hope you dont feel this way Assargadon. Trust me, I wish I had 100's of kits for the community, but I only have a few, and lots of people want them. I figured that I'd give the most active community members a chance at them first, and then notify the general public after a week if they were still any available.

There's still some left, if you're interested in getting one =)

Rationing scarce resources is always a tricky thing to carry off without making some people mad. If you followed a purely free-market model it would probably be best to offer the extruder kits on eBay with a reserve price set to what you intend to charge on the RRRF website when your inventory gets large.

The problem now, as I see it, is that the foundation is undercapitalised. Zach has been a real brick about putting his own money into the venture without hope of gain. Allowing kits to go to the highest bidders for a while might be a good way of bulking up the capitalisation of the RRRF so that Zach could afford to put together a good inventory without facing bankrupcy.

thanks Forrest.

capitalization is one issue, but we're doing pretty well on the money front.

the bigger problem i'm having (with the extruder at least) is that its hard to get these things produced. Luis stepped up to the challenge, but realized that CNC'ing these things can be rather time consuming. One of the things I'd really like to see done is to get the extruder drawings created in the www.emachineshop.com program. that way, we can easily order any number of them. also, we wont be wasting a valuable team member's time simply producing parts, especially on a CNC design that will probably be abandoned once we can reliably print parts.

if anyone here is has some CAD skills and some free time, i'd love to see a mockup of the screw holder done. that would give us a good estimate of how expensive it will be to get the whole extruder done via emachineshop. if its absurd, then we wont have wasted many hours modeling all of the parts, and if its cheap, then we have a nice, reliable source for extruder kits.

any takers? please?

Isn't the casting method shown by Adrian on the main blog the way to go to mass produce extruders in the short term?

In fact in general if you want a lot of some item, FDM is not appropriate because it is so slow. Once you get to a more than a few off making a mold and then casting seems to be the way to go. That is what happens with commercial 3D printing. You get accurate prototypes with SLA, FDM or whatever, you then use that to make soft tooling for a few hundred off and then hard tooling like injection molding to make thousands.

The only way you can make lots of things with FDM is to have lots of machines, which will only happen if the machine can self replicate and lots of people own them. No single person is going to be able to mass produce with FDM, only a mass of people can mass produce.

---

[www.hydraraptor.blogspot.com]

providing that they work, i'd love to get some cast extruder parts. that would be awesome. i've never done casting before, so I'm wary to volunteer. i'm ridiculously busy as well. however, i am definitely willing to pay someone else for their time and efforts in getting those parts made.

i'm sure that if you (anyone reading this) talk to adrian extra nicely, he would be willing to get a mold of the extruder parts made up for you to make said parts. if anyone wants to take up the challenge, the invitation is there...

I can take a shot at the emachinesshop thing when I get home. The issue is that it's hard to get accurate measurements out of the STLs that can be used to create a model of them in a more geometry-driven format. I wish someone who has Solid Edge, the program the printed parts were initially designed in, would save a copy of all of them in an IGUS or STEP format, that would facilitate much more "open" engineering, I think. And any decent CAD package has the ability to save in and open at least one of those formats, and usually both.

Up until now for general measurements I've been using 3DS Max, but as it isn't intended to be a CAD package it has very weak measuring abilities, no surface-to-surface or surface-to-point. Of course, as far as I can tell (not that I've used it much) AoI's measuring is even more primitive - a simple grid.

And it doesn't help that I can't get the free Solid Edge viewer, which presumably would allow me to take measurements from the source parts, running in Vista (Ubuntu is out of the question for it, of course).

Casting is something I've been meaning to try, but I've been lacking anything to make molds from. I've got a half gallon or so of epoxy and polyester resins lying around from some fiberglass stuff I was messing with, so I may give it a try with that and whatever else I can scrounge up. I just need to get over my fear of messing up the shiny new parts.

I'll have a better idea of whether it's within my abilities once I get the aluminum parts in hand. I'm camped out in front of my mailbox right now :-)

The real test will be whether they can get the parts they've cast to work. If they can't make theirs work, I don't stand a chance.

i agree... thats the major what-if there. if the cast parts work, then we're definitely in business.

Better yet. If castings made from the cast parts can be used to make functional parts.
That way, one set of Stratsys produced parts can be used to make one mold, (then put in a safe,). That mold can be used to make a couple hundred parts, (which are shipped out.) Those parts can be used to make a soft mold, for producing in a region.

Personally, I think if the first generation RepRap can produce parts with sufficient accuracy and repeatability, then a second generation casting of a RepRap part, (especially off a commercial system,) should be quite sufficient.

For analogy. Go dig out an old impact printer, (and find some ink for the dried out ribbon...you might also need to find a ribbon that isn't an ink saturated brick.)
Print out one page from a modern word processor, (Word, Wordperfect, Works, or StarOffice should be fine.) Use as a model a page printed on a laser printer.

Now, make a photocopy of the laser printed page. And one of the first copy.

Which copy came out looking cleaner? The impact printed original? Or the third generation copy of a laser printed one, (from a well maintained photocopier.) I suspect the second generation copy would still compete favorably with originals off of early generation equipment.

If I can ever get back to my PCB's and get them done, and if things get calm at work I will be making and casting some of the reprap parts. As a working fabricator/model maker projects at work can tap you out not leaving much for yourself after hours. I've been reluctant to say this as I would never want anyone hanging on my intentions only to find I get no breathing room or relief from my day job and that can very well happen.

So far I've only completed the power/comms and 1 UCB. I just ordered my pic programmer today from sparkfun electronics and we'll see how that goes when it gets here.

I would think by the time things get calm at work, usually around December I may have a chance to try fabbing up a few parts, we'll see.

ZachHoeken Wrote:
-------------------------------------------------------
> One of the things I'd really like
> to see done is to get the extruder drawings
> created in the www.emachineshop.com program. that
> way, we can easily order any number of them.
>
------------------------------------------------------
I can contribute here.
I'll need the dimensions and materials. Former can be read off from 3ds max but its time consuming and not accurate as someone said above.
Not only extruder, we can make models of all parts (including nuts and bolts) so that one can order the whole kit.

They have an estimate tool in emachineshop s/w which tells you how much a part will cost for certain quantity and material. General rule is more quantity==less cost.

If someone can take all the orders and places them at once, it'll be cheaper, instead of everyone taking the model and ordering separately. Once the parts are modeled, someone needs to sample order them and double check everything before asking for a lot.

> I really hope you dont feel this way Assargadon.
Of course I don't. After all, personally I detect this kit, so it was possible to any other (who really want to have one) to detect it, too. Only thing he need is everyday monitoring if [parts.reprap.org]

> There's still some left, if you're interested in getting one =)
I interested, but I was impressed by "buy one if only you are serious experimentator" call. I want one, but of course I can wait some monthes...I have no skills for enchantments of mechanic, so I can only "play" with it.

And one more idea: if we so un-marketed, it maybe time to make next step.
What do you think about some kind of auction with, for example, opto-endstop PCB as a lot.

Of course you can just bought this PCB without auction. It's only form of donation. I think this form is more...funny? affordable?

Like Kyle and Omega I'd be able to help model the parts in eMachineshop. I loaded a few of the STL files in Solidworks, but it unfortunately couldn't take any measurements. Dimensioned drawings or CAD-format files are probably necessary here.

Joost, who has an educational license for Solid Edge, was kind enough to get me an IGES file containing the Darwin assembly. I've imported it into my CAD program of choice (Autodesk Inventor, to be exact) and am in the process of constraining all the peices properly. It'll be a while before I get to a stage where I can be useful (especially since all my electronics showed up a couple days ago, and I'm trying to build/debug them right now) but anyone who'd like a copy of Joost's IGES file can shoot me an email at kylecorbittATgmailDOTcom and I'll be happy to send it to them.

I actually modeled a part called screw-holder just to get an idea. With Al as material and 3axis Mill as machine, the cost comes out to be $10 per piece for a quantity of 100. The cost shoots up if you decrease the quantity.
Steel costs even more.

I have no idea how much this part should cost. Let me know if its worth doing.

Here is the emachineshop file. Its mostly accurate, except at two places I used straight cut instead of circular.

[files-upload.com] (makes you wait)
[6.download-1.files-upload.com] (direct but may not work)

Omega: do I need to download their sotware to be able to see your version?
Can you post a screenshot?

yes, you need their software. however, its completely free...

fantastic work! at that price, we could probably get all the extruder parts for $40/set.

however, now that the cast extruder stuff is coming to fruition, we'll probably be pursuing that route. its cheaper, easier to make, the parts are lighter, and the parts are also clear (talk about awesome!)

thanks for the work guys.

>yes, you need their software. however, its completely free...
Yep it doesn't work in linux. (it installs fine under wine, it runs but hard to work with).

I was able to see the part, but for check the price I was required to fill the descriptions (model, without motor, etc), and fill the payment method too (my mastercard number, etc). So I stopped there.

However I think we should focus on other parts and not on extruder ones. (because there are 3 ways already: the CNC'd from aluminium one, the cast extruder, and emachineshop.com).

So If I understand correctly the current situation, the extruder part kits are more or less resolved(3 ways already).
But the other parts (corner brackets, etc) are missing, and the actual printing has also problems. (any news about printing with the aluminium extruder?)

I think a status update about the printing difficulties would be really welcommed.

ZachHoeken Wrote:
-------------------------------------------------------
> fantastic work! at that price, we could probably
> get all the extruder parts for $40/set.
>
> however, now that the cast extruder stuff is
> coming to fruition, we'll probably be pursuing
> that route. its cheaper, easier to make, the
> parts are lighter, and the parts are also clear
> (talk about awesome!)
>
> thanks for the work guys.

So I understand that I (and two more volunteers above) need not go further with emachineshop and wait for cast parts. Right?

khiraly, it works with Windows only I guess.
It asks for CC number and other stuff when you place an order, I filled up random things for checking the price.
It also updates its price info every now and then, so a net connection is needed.

>
> So I understand that I (and two more volunteers
> above) need not go further with emachineshop and
> wait for cast parts. Right?

yeah, it appears that the cast method is going to be very cheap and fast, so we'll probably go with that. if anything changes, i'll post something here. hopefully we'll get the first batch of cast parts in 3-4 weeks.

Kyle Corbitt Wrote:
-------------------------------------------------------
> I can take a shot at the emachinesshop thing when
> I get home. The issue is that it's hard to get
> accurate measurements out of the STLs that can be
> used to create a model of them in a more
> geometry-driven format. I wish someone who has
> Solid Edge, the program the printed parts were
> initially designed in, would save a copy of all of
> them in an IGUS or STEP format, that would
> facilitate much more "open" engineering, I think.
> And any decent CAD package has the ability to save
> in and open at least one of those formats, and
> usually both.
>
> Up until now for general measurements I've been
> using 3DS Max, but as it isn't intended to be a
> CAD package it has very weak measuring abilities,
> no surface-to-surface or surface-to-point. Of
> course, as far as I can tell (not that I've used
> it much) AoI's measuring is even more primitive -
> a simple grid.
>
> And it doesn't help that I can't get the free
> Solid Edge viewer, which presumably would allow me
> to take measurements from the source parts,
> running in Vista (Ubuntu is out of the question
> for it, of course).

I have time if someone can supply materials and molds.

Although I am UK Based.

Cheers

aka47

---

Necessity hopefully becomes the absentee parent of successfully invented children.