Rapide Lite 350

[Bah]

Hi all,

I have bought an early bird Rapide Lite 350 and I am a little concerned now since there hasn't been any new information made available about the larger models in a long time. The web site (http://i-rapide-3d.com/) now mentions only the 200XL and all information regarding the other Lite models has disappeared. What the?..

Since the design of the 350 has apparently been finalized, it would be appreciated if updated detailed specifications were made available. I for one urgently need real dimensions to finish preparing a space in my cramped workshop for this relatively large machine, among other things. I would also appreciate any up-to-date information on delivery issues, as we have seen with the 200s that things on that front are quite different from what was originally anticipated.

Also, are there any other contributors that are concerned like me about the new twin-extruder design? One of the main features that initially attracted me to the 350 was precisely the presence of two independent extruders. Now it seems that the plan is to fit the new, cheaper twin-extruder head on the 350 as well.

Mr Hunt has proven to be quite the skater as he managed so far to avoid providing any solid answers to many questions, among which the capability of their extruders to handle soft filaments like the NinjaFlex. I strongly suspect that it will be necessary to either modify or outright replace one of the extruders in order to be able to handle such "exotic" filaments, and I am OK with that. I do fit the "advanced user" profile, after all. Where I have a problem is that I now will have to replace the entire head (i.e. both extruders) if I want to be able to handle composite prints (PLA/ABS + Flex, for example). Not to mention cabling issues.

In short, I would absolutely prefer to get what I ordered: a machine fitted with two independent extruders. Anyone else with me on this issue?

Thanks for reading!

[bolsoncerrado]

Was it written in the perk that you would be getting a dual extruder or a dual independent extruders? As you may know prototype pics are often used to illustrate upcoming products and the 350 hasnt officially been launched yet, thats why we back it thru crowdfunding networks.

As for exotic filaments, yes, you need to adapt the extruders for them, but nothing very difficult to make. Just add a printed piece to the extruder.

[bolsoncerrado]

Addressing your concerns on size and dual extruders, here's what Ethan sent me:


"Something below about the extruders … the dual extruder is better than previously for the 350 and it will not be the same as the 200 or 200XL (firstly because its 850gms) and because of the size. we are looking at reducing the size of the 200 to give back more space to the bed but still looking so have not updated. 350 delivery is only now down to full testing of the head bed heating (we fixed the warping) and stability of the logic board to ensure we dont have any issues."


"we are just in the process of redoing the websites and took down the other details because they related to the Rapide Lite 200 campaign and we want to keep the campaigns up to date with the correct details."



Rapide Lite 350

Specifications

Size 450 x 450 x 500mm
Build Size 350 x 350 x 350mm
Build Volume 42,875cm3
Printing Material PLA, ABS, PVA,
HIPPS
Filament Size 1.75mm and 3.0mm
Minimum Layer Height Up to 50 microns
Print Speed Up to 150mm per second
Material Type Non- Proprietary ($15kg)
Mechanism Core XY
Positioning Accuracy 10 micron X and Y
Total Weight 25kg (approx)
Operating System Window, Mac, Linux

Other Features

Print Bed Precision Heated Aluminum
Connection USB, SD Card
LCD Screen 4 Line LCD
Extruder Type Rapide 3D Q Extruder
Number of Extruders 2 (.04 + .08mm)
X Axis X Wing Technology
Chassis Anodized 5026 Aluminum
Frame Anodized 5026 Aluminum
Components Anodized 5026 Aluminum

Retail Price $3999

[Bah]

bolsoncerrado, have you even looked at the specifications you just posted? To begin with, they clearly state that the 350 is to be equipped with two extruders. And yet I'm supposed to believe that "the dual extruder is better than previously for the 350 and [...]" without any details to support the claim, is that it?

And the weight and dimensions are all approximate, pretty much the same as they were before the 350 was even built (that's useless to me, I need real figures).

Anyway, I am writing a clear explanation of what's at stake here, because I suspect that many people don't quite understand the issue, mostly newcomers to 3D printing. It's would be only fair that they too can participate in this discussion. I will post that within a couple hours.

[Bah]

As promised, here's a short(-ish) but precise explanation of the issue at stake for those people who are new to all of this. It's only fair that everyone would understand what's going on.

Everybody living in today's modern world has experienced the vast range of thermoplastics in use today. There's the extremely common, hard and rigid ABS used to make the housing of the monitor on which you may be reading this. There's polypropylene, that oily-feeling, softer and not-quite-transparent plastic used to make so many small storage containers. Polycarbonate (better known as Plexiglas) used to make highly resistant parts. Nylon -- part of the polyamide family -- used to make that bendy and virtually indestructible pocket comb. Then there's the family of thermoplastic elastomers that are used to make molded rubber-like parts, like running shoe soles or shock bumpers, etc. In short, there's a world of possibilities, and that vast selection has just begun to be made available for 3D printing.

The pioneers of 3D printing had to start somewhere and the ubiquitous ABS was chosen for its wide availability. Then the open-source movement introduced PLA as a more environment-friendly choice -- actually, the original interest came from the idea that it could be easily produced in the third-world from locally sourced biomass, but I digress. An added bonus was that both polymers are mechanically similar enough that they can be used inside the same extruder designs. By mechanically similar I mean that both filament have properties not unlike uncooked spaghetti noodles, they are pretty stiff.

Not all of the newer materials available share these properties, however. For instance, the more flexible filaments behave more like cooked noodles! Now, imagine that you are trying to force feed one such noodle into a small opening -- that's what the extruder does with the filament. While it's fairly easy to push on an uncooked noodle, pushing on a cooked one is pretty much out of the question, unless there's some sort of tube to guide the noodle all the way! Not to mention that a gripper capable of pinching a cooked noodle with enough force to push it without slippage may very well tear right through a cooked noodle. You get the picture.

That's what the talk about "installing a printed part inside the extruder" is all about: that magical part is supposed to guide soft filaments inside the extruder mechanism. One certainly could ask if there is room inside the extruder to install such guides and whatever else could be required to support soft filaments...

In fact, has anyone done this with the q extruder? Have you seen a design for said printed piece? Have you seen mechanical drawings for either the twin extruder or the mysterious "printed part"? Have you even seen the inside of the twin extruder? Because I certainly haven't, and without that any claim to the effect that the problem can be easily solved are pretty much worthless.

But before this degenerates into a discussion about what can or can't be done with the super-duper-hyper-marvelous q extruder, let's take a step back and look at the broader picture. The issue is not whether or not the extruder can or cannot handle this or that filament, because it is certain that there are -- or will be -- materials that cannot be handled by said extruder. Nobody knows what materials will be available tomorrow or next week.

That's what is so appealing of a 3D printer based on open-source technology: there's an implicit guarantee that you will be able to adapt and upgrade the printer with widely available components from the very active community. A guarantee that, when that new oh-so-marvelous-material that you absolutely want and need comes out, you will be able to use it without replacing the whole printer.

It may not be absolutely trivial to do so, but if there's any interest for it, someone will figure it out and you'll benefit from the knowledge of the community. That's what is so fantastic of the open-source world. Try to modify a Stratasys 3D printer, just for fun... you'll not only hit a wall but you'll probably end up talking to their lawyers. But I digress again.

Now everybody should see clearly what my grievance is: I purchased a printer that was to be equipped with two independent extruders driven by an open-source controller board. That meant that if I wanted to have one extruder print cupcake molds in material X while using the second extruder to fill the mold with ready-to-cook cupcake batter, I COULD! Or make that a PC/ABS cover with an integrated urethane gasket, if you want to be serious. Or a semi-flex iPhone cover with soft silicone overlays to improve grip. Or anything else you can think of, not just what some guy thinks you should be happy with.

Now, with the twin-extruder modification, I have to replace both extruders and deal with some yet-to-be-documented non-standard single connector to adapt third-party extruders on my printer. I am not happy about that, and neither should you be, IMHO.

'nuff said, unless you have questions for me, which I will be happy to answer. What do you think?

[BobenhamHotspur]

My understanding of the problems with filaments like Ninjaflex is that it's Bowden drive machines that have the most problems due to having to push a flexible filament a long distance from the reel to the heating element, whereas the RL's have a direct drive system so will not encounter any more problems than any other direct drive printer i.e. Ninjaflex is more problematic than ABS/PLA but not insurmountable. Still pondering the benefits/disadvantages of having two independent as opposed to one dual head extruder so will come back on that.

[Fixx]

http://www.thingiverse.com/thing:670689

Here is the part for printing flexible filaments with Rapide Lite extruder, forum member Clayton modeled it. I think you can still print flexible filament without this part with really slow speeds, but this part helps you to achieve a little higher speeds.

[BobenhamHotspur]

I can't state this for certain as much of the original information is no longer readily available but I'm guessing that mentioning "two extruders" in the 'specifications' does not exclude RL from providing 1 dual dual extruder as they would definitely argue that there are "two extruders" in the one unit. Assuming that "two extruders" meant two independent extruders is of course unfortunate if you were reliant on that being the case

NB. Just caught a glimpse of your new post while writing this so will have to read it fully and maybe amend mine if necessary.

[Bah]

BobenhamHotspur, I know what they will argue, I've read most comments on the campaign page and I can pretty much guess what Mr Hunt's reaction will be to all this. Doesn't make it any less real that there were pictures (albeit faked, scaled and distorted images of a 200 prototype) of a supposed 350 with two identical q extruders mounted side-by-side. And the pseudo-500 shown with three such extruders. And there was quite a bit of fluff around the q extruder design, which was supposed to be the next best thing after sliced bread.

Funny that all references to that q extruder are nowhere to be found anymore, and that it's no longer available as a perk. Now, instead of having the option to buy a $75 spare extruder to modify (and possibly destroy in the process) to handle "exotic" materials, the only option I have is to order a $225 proprietary gizmo, a thing that I don't want to begin with.

Also, please read my earlier writings where I explain that it is not really about flex or no flex, but rather the possibility to do what I please with the open-source printer I purchased.

I believe that their decision to change the extruder design was short-sighted. In order to save $20 (if even that) in fabrication costs, they will impart hundreds of dollars in added costs to the end user in the long run. That's what I have a gripe with, nothing else. I do not deny them the tremendous efforts they make to deliver the product, nor the challenges that have risen and that they have bravely tackled. I am simply raising an issue that is real, and one has a definite long-term impact on the owners of the printers.

[milstream]

I think Ethan would supply you with separate extruders if you wanted.
The single extruder is available on the other campaign for 200XL here

http://igg.me/at/rapide-lite-200XL/x/8784579