Next generation of RepRaps, which to build?

Hello All!

I'm not sure if this board is the proper one for this post, but I couldn't find a better place for this. Disclaimer: this is NOT a "which printer is best" post. I have built two repraps and have a Makerbot Replicator at work. I have a fair amount of experience with the various designs and limitations.

My first RepRap was an "Ecksbot" (Prusa i2 Variation). I spent a fair amount of money building the printer from scrap (printing my RP parts on the Replicator at work). But I was never happy with the design (too sloppy and weak/not square). Unfortunately the hotend jammed last January and the printer has been sitting on my shelf, waiting to be scrapped.

I'm thinking about scrapping the printer in December/January and building a new printer. I've been watching the RepRap evolution for the past 9-10 months and haven't really settled on a printer design. At one point I was considering the RepRap Morgan, but I don't feel SCARA printers are stable enough to invest my time/money into building.

Since March, I've been watching the MendelMax 2.0 development and am leaning towards that printer, but I haven't heard much about it. The MendelMax 1.5 still seems to be a popular design, but I really don't want to build another A-frame design. Unfortunately the Hardware kit for the MendelMax 2.0 is still $800 - quite an investment considering I will be scrapping my old printer for parts necessary to finish the MM2.

The Prusa i3 looks interesting, but it seems the design is fragmented. There is no centralized place to post questions and discuss with fellow builders. Troubleshooting problems with the design may be more challenging because of this fragemntation.

I really like the concept of the RepRap Wally, but the design is simply too new, and documentation is limted.


TL;DR - I'm looking for suggestions on a stable well designed RepRap that I can build using parts scrapped from an old Prusa i2.

All new development is going to be experimental by nature. Some of the printers you mention have not been carried forward since they were announced.

I think you should give the Prusa i2 another go, but get a decent hot end. [www.hotends.com]

Stick with bushings and flex couplings for the Z axis. LM8UU for X and Y.

Go with this extruder [www.thingiverse.com] It has all the things I like about Greg's, but more compact, and easier to print.

If you want to make it more reprappy, go with these (optional) addons [www.thingiverse.com] [www.thingiverse.com] [www.thingiverse.com] [www.thingiverse.com] (Disclaimer: my designs)

To lighten the load on the printhead, try this X carriage [www.thingiverse.com] (Disclaimer: my design)

And it should go without saying, print everything in ABS. Just MHO.

I understand the expiremental nature of the RepRaps, but some designs have much more documentation and a larger support community than others. When building my Ecksbot, I had a forum support community of approximately 10 active members. Asking questions required days of patience waiting for a response from the forum visitors or the Ecksbot team. Wherease when I built my Rostock max from a kit - the community forum was FULL of visitors. Most questions I posted had multiple answers within an hour or two of posting, even if I posted at 1 in the morning!

Sadly, I will not be re-using the Prusa Mendel in it's current configuration. The z motors are suspended from the top (can't count how many times my X axis came lose from both sides and crashed into the bed!). Both X and Y carriages are loose and not tightly secured to the linear bearings. I do have a replacement Hotend from Hotends.com, but once mounted, it decreases my max print height by 35mm! And the lack of community support for the Ecksbot has led me to the decision to scrap the printer and start fresh, nothing aside from the electronics and hotend are worth salvaging to me.

Overall, I wasn't satisfied with 8mm threaded rods, they aren't square enough for my tastes (and bend when overtightened!). If anything, I would consider buying the alminum extrusions and build the MendelMax 1.5, but I feel most of the designs appear to be converging on a 90-degree shape, moving away from the A-frame design. Honstly, I think I'm looking for the best printer design with Aluminum extrusions, which I asume narrows my options to the Mendel90 and the MendelMax.

How are makerslides? If I did consider the MendelMax 1.5, I would opt for the 1.5+ model which replaces the Y axis linear bearings with a makerslide.

First question - why are you scrapping the whole printer just because of a clogged hot end? Are there limits to the functionality/design that you need to overcome with the next printer? What are your requirements and what are looking to make? That's a great place to start...

As far as a possible solution, I'm in the middle of building a Lulzbot Taz clone, and it may be worth a look for you. Its overall design is somewhat similar to the MendelMax 2.0, but uses printed parts to connect the Misumi extrusions. I would think that you should be able to re-use many of the parts from your i2. If you upgrade nothing more than the frame, smooth rods, z-leadscrews, and add some longer belts I don't think you'll spend more than $400. The BOM and STL files for all of the printed parts are freely available from Lulzbot. They have their own forum with lots of great information, and they are very responsive to questions even if you didn't buy a printer from them. There's also a growing library of upgraded and customized parts on Thingiverse and I will soon be adding more of my own.

Stonecoldskier

Simply put, I am not impressed with the design of the Ecksbot. The threaded rods require very precise adjustments to make everything 'true' and square. The rods are also susseptable to bending, hell they aren't even entirely straight when purchased new from mcmaster! Moreover, the X and Y axis are loose. Aside from some acetone glue (which has come loose), there is nothing holding the carriage to the linear bearings You should have seen this thing in action - the whole print head would bounce around over bumps in the plastic, it wouldn't smooth them out as it normally would if the X axis were properly secured to the rails. Overall, I *could* fix this printer, but it's simply not worth it, I'd spend countless hours rebuilding every aspect entire printer anyway. Now is my opportunity to learn from my mistakes and build a better printer.

I'm looking for a printer design that's cheap to source the hardware, uses aluminum extrusions for the frame, and a ridgid design which can survive hours of use without constant monitoring at moderate print speeds (60-80mm/s).

I haven't looked at the lulzbot taz, but I'll check it out, thanks for the suggestion. I really like the idea of printing my own parts on my Replicator. The Makerbot Replicator has been a champ since we purchased it in September 2012. The print quality is phenomenal, better than anything I've done on my Ecksbot and my Rostock Max!

Actually, looking at that Lulzbot TAZ, that may be exactly what I'm looking for. Now I need to start researching to determine what hardware I'd need for this project..... Any other suggestions are welcome, I'm not ready to pull the trigger yet

Edited 1 time(s). Last edit at 11/19/2013 01:59PM by cassetti.

Cassetti - I didn't mean to make you explain it again, your response to jcabrer must have posted while I was typing. I think you'll like the Taz design for its relatively low cost and ease of sourcing parts. I chose to include some additional corner brackets (http://www.thingiverse.com/thing:105900/#files) to increase rigidity after other users questioned it. It was a simple upgrade to incorporate from the beginning, but I'm not sure that it was actually necessary. I also chose to use stepper motors with captive leadscrews (http://robotdigg.com/product/39/Threaded-Rod-Nema17-Stepper,-with-460mm-Tr8*12-Acme-Leadscrew), rather than any variety of flexible couplings. That was a bit of a pricey upgrade, but the motion of my Z-axis is simply gorgeous when compared to that of my Prusa V2.

I would avoid all printers where the printed objects moves in any direction other than Z as they all suffer from the same issues with the moving mass and vibration that lower the print quality (yes you can tune one to get good prints but not as easy as the following types of machines). So that leaves you with geometries like: Delta (3DR, Kossel, Rostock), CoreXY (don't know any by name), Etch-e-sketch (Ultimaker, Tantillus, Ingentis).

---

FFF Settings Calculator	Gcode post processors	Geometric Object Deposition Tool Blog
Tantillus.org	Mini Printable Lathe	How NOT to install a Pololu driver

I've started building Mendel Max 2.0. In fact my waterjet contractor is my first customer. I've had a few of my commercial suppliers inquire about printers and most wanted larger build areas and something that looked more robust and were willing to pay for it. The MM2 I think by definition is a Repstrap using Adiran's definition. Regardless, I see it as a great bridge between home/hobby machines and entry level pro machines. Nothwithstanding, an i2 or Sells Mendel can produce some good prints but there are things on the MM2 that are attractive. Larger build envelope is one. Another is the reported speed though in looking around the current hotend/extruder technology appears to be more of a liniting factor. A factor for another customer who owns a Replicator is the ability to print higher end plastics and nylon. I'm waiting on a few more bits though I'm hoping by end of the week the rest of the part arrive.

The hardware is expensive because the hardware is expensive. The 27 or so cut plates are the greatest cost of the frame if they are laser or waterjet cut. You may be able to use something less expensive or cut the plates yourself by hand though one would have to be pretty good to do such. The extrusion parts are available at Misumi or 8020 or from China. The motion parts aren't cheap either though widely available from Misumi, Igus, PBC or China. They're made to exacting tolerances and there is a cost to that. There are only several hundred MM2s in the wild at this point but it's early in the machine life cycle. The sources were released in June and the cost is certainly a barrier to many. As for docs, what's posted at Makers Tool Works is some of the best documentation I've seen on an open hardware (or even OSS) project in the nealry 20 years I've been involved in open source. Clearly explained; solid, current BOM; plenty of pictures including a 3D pdf and sources for all the parts including the mechanical bits so a complete assembly can be generated as a model. The hardware build manual is 78 or so pages with another for electronics.

Here's a shot of the first frame I assembled from the BOM and sources available online. The rest of it goes together pretty easily as well.

Persoanlly, I'd be looking at a Simpson. They seem to be the closest to a true RepRap than anything out now.

Quote
Sublime
I would avoid all printers where the printed objects moves in any direction other than Z as they all suffer from the same issues with the moving mass and vibration that lower the print quality (yes you can tune one to get good prints but not as easy as the following types of machines). So that leaves you with geometries like: Delta (3DR, Kossel, Rostock), CoreXY (don't know any by name), Etch-e-sketch (Ultimaker, Tantillus, Ingentis).

Thanks for that. I already have a Rostock Max kit which I purchased from SeeMeCNC back in February 2013. I still need to fix the hotend (shorted the thermistor), and need to rewire it, but that printer is built with machined and injection molded parts. That printer is awesome, though I hate the 0.5mm nozzel, I might need to modify that eventually once I get the other bugs worked out of that printer.

Mainly I'm after a second printer I can play with. Since I already have several hundred dollars worth of parts from my Prusa i2, I might as well make use of them. I'm really not too concerned about a minor hit in print quality from using printed parts. I have a Replicator 1 and my Rostock Max which have no printed parts. If I need something printed with precision, I can use either of those.

Quote
vegasloki
I've started building Mendel Max 2.0. In fact my waterjet contractor is my first customer. I've had a few of my commercial suppliers inquire about printers and most wanted larger build areas and something that looked more robust and were willing to pay for it. The MM2 I think by definition is a Repstrap using Adiran's definition. Regardless, I see it as a great bridge between home/hobby machines and entry level pro machines. Nothwithstanding, an i2 or Sells Mendel can produce some good prints but there are things on the MM2 that are attractive. Larger build envelope is one. Another is the reported speed though in looking around the current hotend/extruder technology appears to be more of a liniting factor. A factor for another customer who owns a Replicator is the ability to print higher end plastics and nylon. I'm waiting on a few more bits though I'm hoping by end of the week the rest of the part arrive.

The hardware is expensive because the hardware is expensive. The 27 or so cut plates are the greatest cost of the frame if they are laser or waterjet cut. You may be able to use something less expensive or cut the plates yourself by hand though one would have to be pretty good to do such. The extrusion parts are available at Misumi or 8020 or from China. The motion parts aren't cheap either though widely available from Misumi, Igus, PBC or China. They're made to exacting tolerances and there is a cost to that. There are only several hundred MM2s in the wild at this point but it's early in the machine life cycle. The sources were released in June and the cost is certainly a barrier to many. As for docs, what's posted at Makers Tool Works is some of the best documentation I've seen on an open hardware (or even OSS) project in the nealry 20 years I've been involved in open source. Clearly explained; solid, current BOM; plenty of pictures including a 3D pdf and sources for all the parts including the mechanical bits so a complete assembly can be generated as a model. The hardware build manual is 78 or so pages with another for electronics.

Awesome! I really haven't seen many people building the MendleMax 2.0. Which suprised me, given the popularity of the MM 1 and 1.5, I've been watching the MM2 since it's announcement. I was hopeful to see more excitement from the RepRap community towards the MM2.0, but so far it seems to be a resounding "meh". Also, since my Rostock Max has an 11" round bed and a max height of 14.5 inches, I'm really not after a large print volume, I'm after a printer that I can assemble and get back to what I enjoy - printing stuff!

Quote
SheldonE
Persoanlly, I'd be looking at a Simpson. They seem to be the closest to a true RepRap than anything out now.

If by "true RepRap" you mean poorly documented, fragmented information, and a lack of complete assembly instructions, sure, why not. The RepRap Wally has more potential then the Simpson since it's further along in development. But personally, I'm interested in a stable printer design which I can build and get back to printing. If I had the money, I'd buy an assembled printer and call it a day. I'd rather spend more time focused on learning and using OpenSCAD, than tinkering with a prototype

Thanks all for the suggestions, keep them comming!

Edited 1 time(s). Last edit at 11/20/2013 09:41AM by cassetti.

I don't see the MM2 appealing to most DIY Reprappers. The appeal is for those shops that are looking to get into a machine, don't mind spending a couple grand and be able to print more types of plastic and nylon. These guys have looked at entry level machines from 3DS and others and are willing to spend a few grand to get up and going to test the waters but not $10 or $20 grand for one of the name brand machines. If it takes off for their shops they could invest in a larger machine or build on what they have. If it doesn't they aren't out a bunch of money or tied into a long term lease. The smaller maker shops seem interested because of the potential to change tool heads to laser or mini mill.

I like the Simpson. Had I more time I'd put one together. There was a similar evolution in robotics for manufacturing where the designs went from a cartesian style to a movement style similar to the delta bots.

Quote
vegasloki
I don't see the MM2 appealing to most DIY Reprappers. The appeal is for those shops that are looking to get into a machine, don't mind spending a couple grand and be able to print more types of plastic and nylon. These guys have looked at entry level machines from 3DS and others and are willing to spend a few grand to get up and going to test the waters but not $10 or $20 grand for one of the name brand machines. If it takes off for their shops they could invest in a larger machine or build on what they have. If it doesn't they aren't out a bunch of money or tied into a long term lease. The smaller maker shops seem interested because of the potential to change tool heads to laser or mini mill.

I like the Simpson. Had I more time I'd put one together. There was a similar evolution in robotics for manufacturing where the designs went from a cartesian style to a movement style similar to the delta bots.

You've got a very valid point. I've been blinded by the popularity of the MendelMax 1.5 and all it's variations that I assumed the Max2 would be the logical evolution for the printer, and everyone would follow it's design.

The Simpson however appears to be still in it's infancy, much like the Rostock was in August 2012. Since I've already got a Delta printer at home, I think I'm going to stick with a Cartesian Coordinate system until I see a SCARA based design I like.

Currently, I think I'm leaning towards building a Lulzbot TAZ as I believe I have nearly everything I need to make that printer, maybe need to spend an additional $200, but far less than the $800 I was looking at spending for the MendelMax2

Quote
cassetti
The Prusa i3 looks interesting, but it seems the design is fragmented.

Yup. And figuring out which parts I wanted was a pain (but a fun hobby-type thing to do.) But I think your conclusions (no online support, more difficult troubleshooting) might not necessarily follow. And all your steppers and electronics, and gears/pulleys get recycled from your i2.

I'm in the process of building an i3, and with the experience of an i2 in my back pocket, there's nothing about this machine that intimidates. I've only got the frame together thus far, and I'm very pleased with its stability. The other printers you mention (I suspect, but do not know) don't have the same adoption rate of the i3, which would make i3 support easier to get. I'd be interested to hear dissenting opinions on that, though.

I was in the same boat as you, and went the i3 route. No regrets thus far.

Look at

[www.3ders.org]

It's a 3D jungle out there!

Perhaps a Rigidbot?

[inventapart.com]

Maybe an Ordbot Hadron

[buildlog.net]

From my perspective as a supplier and OEM in North America the i3 is far and away the most popular DIY Reprap. There are several frame choices but the mechanics are similar if not identical and there is a robust community to lean on if need be.

Quote
cozmicray
Look at

[www.3ders.org]
It's a 3D jungle out there!

Perhaps a Rigidbot?
[inventapart.com]

Maybe an Ordbot Hadron
[buildlog.net]

Lol, yeah, I am an RSS subscriber to 3ders.org - great site.

I think i've seen an ordbot hadron before, but don't know much about it - seems pretty small, but I like the fact they're using makerslides.... Time to do some more research!

Quote
vegasloki
From my perspective as a supplier and OEM in North America the i3 is far and away the most popular DIY Reprap. There are several frame choices but the mechanics are similar if not identical and there is a robust community to lean on if need be.

Interesting. I really wasn't that "wow'd" by the i3 design in general. But I agree, it does seem to be one of this year's hotest designs.

I can tell you what I'm doing. I'm building an i3. The documentation (or lack thereof) is very frustrating. On the other hand, the openscad parts give me a lot of flexibility. I found motors on ebay that kick butt. They have high torque and included heatsinks... dirt cheap. Unfortunately they had 4mm shafts. No problem, I printed custom z motor couplers to tie to the 5mm threaded rod. I also have to print a custom gear for my extruder so that it will fit a 4mm motor shaft. When I didn't like an aspect of the y tensioner I simply modified the script and generated a new stl. When I wanted to use a different bearing for my idlers I simply modified the scripts and exported a new stl. You have infinite flexibility with your hardware.

At the same time I'm not in a hurry. I can afford to take my time and plunk around on this thing for the next four months. The only thing that aggravates me is a lack of answers. When it comes to using the latest and greatest parts your pretty much on your own. There is a vanilla repository that everyone in North America seems to build on. May want to check that out.

With the Mendel Max 2 its all water cut plates right? How is this any different than just buying a commercial machine?

I dunno. I could swing 850 - 1000 on a printer. I think my i3 is going to come in right around 550 when I'm finished. But more importantly I will have learned a great deal about 3d printing along the way in making it. I can tell you that simply modifying the scads and printing my own parts is very educational.

I think the i3 is a good balance of both worlds. You have a thick water cut aluminum plate that everything is bolted to giving you max stability and a nice clean, simple, professional look. And all of the plastic bits are the critical pieces that give the machine it's properties and make it possible in the first place. So when you feel something could be improved you simply print better components and modify the machines nature. I think that's really the point of reprap.

That was my reasoning anyway.

I've built a few Prusa i3, and they are okay. Not more not less, just okay. I don't quite see the reason for the huge buzz around them. Maybe it's like the Volkswagen Beetle. It was okay as a car, but man did they ever build a lot of them...

I should also point out that the J-Head is a good hot end, but it is a step down from the Eckertech all metal hot end, if that is the one that is in the older Prusa.

---

Yvan

Singularity Machine

There is the ob 1.4. [www.thingiverse.com]

Quote
Yvan
I've built a few Prusa i3, and they are okay. Not more not less, just okay. I don't quite see the reason for the huge buzz around them. Maybe it's like the Volkswagen Beetle. It was okay as a car, but man did they ever build a lot of them...

I should also point out that the J-Head is a good hot end, but it is a step down from the Eckertech all metal hot end, if that is the one that is in the older Prusa.

The i3 popular because it's inexpensive and easy to source and build. There is now a pretty large community to lean on for support and some pretty good documentation though the number of variants is an issue for some. I'd say a good amount, many if not most with which I deal on the consumer level want to print, not so much build a printer. They build because they can do it at a pace that fits a budget and still not spend too much in the end. Much of the same holds true for a JHead. They are affordable and consistent (from Brian) and easy to tune.

Quote
Dorian
With the Mendel Max 2 its all water cut plates right? How is this any different than just buying a commercial machine?

For starters the design is open and available. The design is a 2020 extrusion frame with aluminum parts to join it and precision motion guides/components. It's about the same price as a less capable commercial machine and significantly less expensive than a comparable build envelope size commercial machine though quite a bit more expensive than a DIY Reprap. The price performance I think is better than a Replicator model due to a larger build envelope, more open design for customization and sourcing and out of the box availability to print in various materials other than ABS and PLA.

Edited 1 time(s). Last edit at 11/23/2013 10:52PM by vegasloki.

For the TAZ, we have uploaded our manufacturing assembly line visual work instructions here:

[ohai-kit.alephobjects.com]

We have also made the OHAI-kit (Open Hardware Assembly Instructions) free software:

[github.com]

-Jeff

Good work Jeff. There are a lot of possibilities with the OHAI-kit.

Wow! So suprised by the response I got on this board, thanks everyone!

I'm still not ready to buy parts and start building yet (too much other stuff going on at the moment), but I'm still very much interested in seeing everyone's suggestions.

Funny though, it seems many of the RepRap designs are converging on a 90-degree design

I have been printing with an ORD Bot Hadron for about 6 months now. It's been an excellent machine. I've run 20 kg or so through it in that time.

I think it's not your kind of machine , as it seems you look for the perfect top notch reprap , but i started an all project : smartrap some weeks ago now .
The goal is to bring the most simple to build ( and unbuild? ) reprap.
I expect to have it working really well in something like 2 months. For now , it's still updating a lot.
Documentation (in 2 languages ) are in top list. It's a well known problem for a lot of reprap projects