Revision 1 of the Replicape is done! There are quite a lot of changes to this new version. The most prominent is perhaps the moving of the thermistor and fan connectors. The thermistor connectors are now located much closer to the analog inputs and have separate ground planes. In addition, there are end stop connectors for both sides of the axes.
The list of “bug fixes” is also quite long including pull-up resistors for the I2C chips, switching VDD_5V and SYS_5V etc.
Here is the complete list of changes:
- Changed the PWM line of Heater_ext_1 to P9_14
- Changed the PWM line of Heater_HBP to P9_16
- Changed the PWM line of Heater_ext_2 to P8_13
- Changed the Fault_x pin to P8_4
- Changed the 3 pin dip switch for a 2-pin dip switch
- Added a DNP pull-up on the CAT24C256 EEPROM memory.
- Changed SCL and SDA for PCA9685 to I2C2 (i2c-3), the same as the EEPROM
- Moved X10, X11, X12 out on lims.
- Added three more end stops.
- Added comparator LM339 as a driver for MOSFETs (296-9544-1-ND)
- Moved the MOSFETs further apart
- Made a separate ground domain (AGND) for the thermistors
- Added three connectors for servos – should not be populated
- Switched to 2×23 pins on both sides
- Added a 100uF cap to compensate LC spikes
- Switched sides for the MOSFET drivers (for easier debugging)
- Added one more 0.1uF ceramic cap near VMM2.
- Switched places for the caps near Y, Z, Ext1, Ext2
- Added more thermal vias for the SMDs
- Switched the M24C16 EEPROM out with M24C256 to allow for proper addressing
- Added 5.6K pullups on i2c-lines
- Connected p9_1 to ground.
- Placed the all heaters on dedicated PWM outputs from BeagleBone.
- Switched channels for ADC on Ext1 and Ext2
- Switched +5V and SYS_5V.
Hopefully the nice people at CircuitCo / Texas Instruments will accept these changes and start production of rev 1 instead of rev 0.
Very nice! Any idea what the target price will be for your Replicape once available?
Gp, I do not know what the target price will be. I just got an e-mail from CircuitCo now asking for all files needed to evaluate the best path. What I can say is that this is not meant as a low end cheap product. Instead it is a high end 3D printer electronics project far away from Arduino. To quote Desiderius Erasmus: “In the land of AVRs, the man with an ARM is king”, or something like that : )
The cape competition max price for the components was $60 so I guess that that is one indication of the price…
Andreas, you are right, but that is the unit price in volumes of 500.. I think the BOM is about $80 for 1 and 40-50 for 500.
Your Replicape and PyPRUSS repo is getting a lot of interest from the LinuxCNC folks, in fact this morning I think they sent over their proposed next generation architecture for a userland version of LinuxCNC that doesn’t require the use of an RTOS on the controller. Are you going to be keeping all of the hardware designs open source for the experimenter/hobbyists out there or will Replicape be a 100% commercial endeavor?
GP, if it was up to me I would keep everything open source! My understanding is that BeagleBoard.org/CircuitCo wants this too, so I see no reason for it to become closed source : ) But it is very good that someone is starting production for this, that means it will become available, hopefully with major retailser. Happy to hear that LinuxCNC people are interested in this work! They should be also be interested in my two last posts on this website. For me they were both big breakthroughs : )
http://hipstercircuits.com/?p=489
http://hipstercircuits.com/?p=468
Hi again Elias,
Have you released a bill of materials yet for a complete CNC machine build based around Replicape? I am evaluating the Lulzbot and Makerbot Replicator 2 (both of which have ABS support); does your design include ABS support yet, and if so, what are you using for the build platform stability and heating? Do you have dual extruder support for mixed to color output? And last but not least, what is the build resolution of your current extruder design in terms of smallest wall lengths, minimum horizontal layer sizing etc?
I guess the more direct question of this. Based on your current design, is it possible to build a CNC machine around your Replicape so far, and if so, what would the general pricing be for everything including the frame, built plate, extruder(s) and thermistor controls etc?
GP, I am working on a “HipsterBot” (working title) design, but it will be while before it is ready for the public. I’m hoping it will be ready for the European Makerfaire in October. If you want a working machine before that, I suggest you look at the two you mention and also
Ultimaker and ORD bot.
The “HipsterBot” will most likely have two extruders with an H-type belt configuration for the XY-axis and a black acrylic frame for stability. I like your idea for using the Micorax as a sturdy frame, but at least for prototyping, it’s acrylic for HipsterBot. It’s cheaper, lighter (transportation costs) and gives a better finish.
Silicon heated bed of 300x300mm.
Mixed color output is still experimental at best as far as I have seen on the interwebz. I have some ideas for that as well, but not for this Makerfaire : )
If you want to help with the development or be a beta-tester, I’m sure we can arrange something.
Sure I would love to help out with beta testing your design.
Have you done much analyses of the current desktop 3D printer options? The Lulzbot is getting good reviews with ABS support, but I am not familiar with the Ultimaker or ORD bot.
Which one would you opt for, if precision is a requirement? Some of the components I want to leverage 3D printing for are very small (~5mm) so accuracy is the key for what I need with a desktop 3D printing setup.
I know a thing or two about the desktop market, yes, but I cannot give a recommendation here. Event though the theoretical resolution is high does not mean that the end result will have a high resolution. Often it’s mechanical inaccuracy that is the limiting factor. Also, you must consider ease of build and repair. A 3D printer will most likely require maintenance, so a simple design along with open source goes a long way. What good is high resolution if the thing does not work : )
Are you sure about the ABS support for Replicator 2? I think i’t only PLA, since it does not have a heated build platform.
MakerBot announced the Replicator 2 Experimental a few days ago:
https://store.makerbot.com/replicator2x.html
I think it’s ABS-only with a more stable heated build flat. It’s also very expensive for something labeled “experimental”, which is why I’ve been looking at the LulzBot as a lower cost alternative that can do ABS extrusion.
On other question… what are you using for your bot frame? I am thinking MicroRax, do have any experience with this: http://www.microrax.com/Kits/Pro-Kit-p15.html
From looking at the Lulzbot it appears to be based on MicroRax but I can’t tell from the low resolution of their product images on the website.
is anyone producing the replicape pcb for availaibility now , or any board houses etc
Davey, Replicape is going to be produced by CircuitCo, the company that makes the BeagleBone and a lot of other capes. From what I understand it will be sold online and depending on demand also from some component distributors such as Mouser and Digikey. If you want to make one yourself, you can send it in to Seeed studio or similar, but in total one board will set you back some $150 including shipping, taxes and components. Also you have to be quite handy with a reflow oven : ) If you are interested in contributing to the project, I can perhaps send you one of the rev 0 boards..
$150 is dirt cheap considering the MOSFETs and everything else in your design. Does Seeed provide board stencils as well for reflow or do the stencils have to be printed/purchased separately?
The Seeed PCBs are pretty good quality for such a low price. For designs where speed (transmission lines) are not an issue, they work fine. Solder masks and stencils for both sides are included. Actually, the driving cost is the stepper motor controllers. Texas Instruments charges some $6 each for them, but they have a higher current rating than the A4988 (which are used in most setups), down to 1/32 micro stepping, over current- , under voltage- and temperature protection so you do not have to worry about destroying the ICs due to pulling the out the stepper cable. God knows that has saved me a few times already : ) In my opinion this is worth the extra couple of dollars.
Is there a public link for the Replicape at Seeed Studio? Or would I have to create a separate account and then go through the PCB Fusion process?
GP, there is no public link for Replicape on Seeed studio. I just sent in the Rev 1 design this week, so I think it’s best that I check the design first to make sure it is working as expected. If you want, I can make one for you or send you one if you are handy with a reflow oven. What is your current setup? Do you have a 3D printer that you are currently using?
So any news on when this will be available. I’m ready to start playing
Bryan, if you want to contribute, I can sell you one right now. I bought parts for 5 Replicapes. One of them went to Bob in USA who wanted to add web services to his printer, three will be stuck here with me, but I still have one last one left that can be given to someone willing to be an early adopter : ) I have soldered it up, but not yet had the time to test it. I sold the last one to Bob for $179 which is a steal considering the $90 BOM.
BTW, what printer do you have?
I’m building one. I’m thinking of a MendelMax. I’ve got access to a machine shop to do a lot of the metal work.
I’d be game to buy one off of you. send me an email of how to get you the funds.
Oh, the MendelMax looks good. I’ll send you a PayPal invoice as soon as I’ve tested it and made sure it is working properly!
Can’t wait for it to arrive.
Bryan, it was sent today : )