Delta Machine Electronics

Heck of a first post...I realize that but I need help here.

I am in the process of building a delta style 3d printer. eventually i will detail it out fully and make the plans available but in the mean time i need some help with the electronics end of things.

here is a link to the current build: Ball screw style delta printer

i purchased a basic kit off of ebay to get me started...

[www.ebay.com]

I have been doing a lot of looking online (researching this stuff for almost a month) and i am trying to make heads or tails of everything. I understand the RAMPS v1.4 plugs into the Arduino Mega but do i need to add any jumpers to the Arduino? I understand how the stepper drivers are oriented and how the breakout board for the LCD panel attaches...(still need to add heatsinks to 3 of the stepper drives)

I am also looking at power management... I know the Arduino takes a USB and has a jack for a power cord (5v) but since the RAMPS board is plugged into the arduino and i have to feed power into the RAMPS for the hot end heater and potentially for the heated bed (doing to do an SSR for the heated bed) do I really need the power into the Arduino direct? I have also read somewhere that i can do just that but need a diode on the RAMPs board.... this board does not have one or the pins soldered intot he board in the proper spot.

I am savvy enough that I have taught myself a lot of things. I am a machine designer by trade but I have no one to lean on for this electronics stuff and im not sure where to go for some better help... so i turn to you guys.

Thanks in advance,

Jason

Only get Arduino Mega/RAMPS if you can't afford anything better. It's underpowered for driving a delta, has a slow USB interface connected over a serial port without flow control, a fragile voltage regulator, and no SD card socket (you have to add an LCD control panel to get one) There are much better boards available now, such as Duet, Smoothieboard, and AZSMZ Mini. Currently, you will find delta calibration much easier with the Duet than with anything else, because of its fast auto calibration function in the firmware.

[EDIT: I just followed your link and I see that you already got Arduino/RAMPS. Oh well.]

Edited 2 time(s). Last edit at 04/17/2015 07:16PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Hi,
I assume this is your first 3D printer build, and you have chosen to design your own delta. I took a look at your design in the link you posted above.

To be totally honest with you, my advice is to take it easy, it seems to me you are trying to do too many things at once and will quickly encounter many rather non-trivial challenges ahead.

Imho a more reasonable approach would be:

1. Buy a Prusa i3 kit, build it and get a good understanding of how 3D printers work. Note that once you are done with it, you can always sell it.

=>

2. Buy a Kossel Mini kit, build it and get a good understanding of how linear delta robots work and the specific calibration issues they have. Again, once done with it, you can sell it.

=>

3. Get back to work on your own original design with more knowledge and more experience.

I second Andrew's advice to start with a kit, although I see nothing wrong with building a Mini Kossel from a kit as a first printer. Building from detailed plans instead might be OK if you have access to a machine shop and a friend who can print parts for you. Designing your own if you are new to 3D printing is not to be recommended.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

im not totally new to 3d printing. i have access to and have ran a makerbot replicator 2x. I am familiar with cnc machines...and i have been a machine designer for 10yrs. I just have not had a whole lot of experience with the electronics side of things.

the mechanical parts are a non issue.

i thought message boards and forums are supposed to be there to help people with issues they are having? So far I have yet to see an answer to ANY of the questions i posted... just two guys telling me..."your in over your head...just go buy a kit..." which isn't really much help...

Edited 1 time(s). Last edit at 04/17/2015 07:37PM by Freebird01.

This [reprap.org] should help answer your power supply questions. You do not need to add any jumpers to the Arduino, but you may need to add jumpers to the RAMPS to select the microstepping factor that you want.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I was on that page...not sure how I missed it. Thank you!

I did find a webpage that talked about the jumpers on the ramps board and was able to install those.

whether its a mini kossal or any other delta machines....a delta is a delta... the way the mechanical parts are relevant only in the screw pitch that dictates your movement. I can only assume I will have to adjust the program to compensate for that.

If i would have found some better info online before ordering i probably would have went with the duet board. however, i have this setup now. I at least want to get this printer running with what I have then upgrade it and re-purpose the arduino/ramps later for a different project perhaps.

the Makerbot is a pain in the rear to use. Its built so lightweight that you look at it too hard and components flex. thats not good when your trying to run dual heads or trying to calibrate the base plate.


Thanks again dc42 for answering my questions!

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Freebird01
whether its a mini kossal or any other delta machines....a delta is a delta... the way the mechanical parts are relevant only in the screw pitch that dictates your movement. I can only assume I will have to adjust the program to compensate for that.

Yes, you will need to adjust the steps/mm setting, which should be in the Configuration.h file in the Marlin firmware source (if you run Marlin, that is).

Good luck with your build!

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I haven't decided on firmware just yet. i'm finishing up the mechanical portion of the build and the wiring before i jump into the programming.

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Freebird01
the mechanical parts are a non issue.

Are you open to some peer review of your mechanical design, or do you want to go through the process as a learning experience and possibly throw some parts away?????

your welcome to comment just keep in mind its not totally complete. also not all of my pictures have been posted. i actually have it mostly assembled already. all the printed parts i needed have been done and its about 2/3 assembled. it moves as it should im just waiting to get the ball screws back from the machine shop.

Two quick thoughts:

1) The carriages appear to be using just three wheels to ride on a round tube extrusion. If so, you may want to add another set of wheels in a vertical line to the first set. The current layout looks like a recipe for unwanted vertical rocking to me as the rods "lever" push/pull on the carriage, and there must be a reason why OpenBuilds uses 4 wheels per axis and AndyCart's original Cherry Pi (and many Kossel carriages) uses three wheels per axis on the extrusion:

http://www.thingiverse.com/thing:210028

2) The biggest benefit to the Delta design is print speed. Past attempts to use screw drives on Deltas have never taken off because they supposedly sacrifice speed. Once you have yours running, you may want to look at some YouTube videos of belt-driven Deltas and see how your printer compares.

My $0.02 USD is that there is too much "kit think" in RepRap now, where everyone keeps building the same tired (but proven) designs instead of trying to improve them or come up with something new. I started out with a pile of OpenBuilds goodies and no working printer, and am now building my 4th generation printer without the benefit of a kit. That doesn't mean that I did not closely examine almost every kit on the market to see what works, and borrow ideas where they made sense.

With that said, I (and a few others) are waiting for someone to utilize OpenBuilds' new C-channel extrusion to create a new Delta design. I'm currently in the middle of a HotBot2 spinoff build, so I do not have time/space to try it out myself.....

Edited 1 time(s). Last edit at 04/18/2015 07:50AM by vreihen.

i understand what your saying about the carriages. By them selves they will bind. i originally was going to put another set of bearings below the carriage but really the bearings are there to prevent any flex in the ball screws. i am using 16mm ball screws so the nut will keep the carriage square to the columns. The screws are 900mm long. this whole machine is based on a total height of 36"

right now i have the motors setup as a direct drive, but if need be i can change it to a belt drive and play with pulley sizes to up the speed of the screws. all of the builds i have seen have stuck with all thread or acme screws. with a ball screw i can reliably spin it faster then the others and have no backlash.

I also plan on adding some lexan panels on 2 sides of the frame. this will act as a sort of cross bracing and will make the entire frame very rigid

This is a post to David dc42 and anyone who has had similar difficulties establishing communication with the Duet board:

First, sorry if anyone has addressed this issue elsewhere in the posts, and I very much appreciate how supportive everyone is here, especially David, that's what led me to purchase the Duet! I received the Duet board from think3dprint3d, but I'm having a rough time communicating with it via Bossa or even SAMBA. I note that the USB socket prongs did need soldering, which I corrected, but other than that the board looked ok (R61 and R60 look reworked so I think they are in the right position--they are both oriented perpendicular to the long axis of C5).

I followed David's Mini Kossel blog instructions for flashing the firmware you wrote, but got immediately stuck at the step to use Bossa for that. Neither the command line approach or the Bossa GUI approach gets communication with the board.

I'm running W7 64bit, and my OS recognizes the board correctly as a Bossa Program Port with a reported comm port 9. However, when I run Bossa and try to select the comm port, Bossa reports "Could not connect to device on Comm 9." I noted the driver's port settings were 9600/8/none/1/none, and I did change the speed to 115200 and still no luck. Perhaps I don't have the proper comm settings? I've tried various USB ports and cables, running Bossa as an admin, that sort of thing.

Can you suggest any other steps that could help me with this problem? I really appreciate any help you can give me.

Cheers,
Blake

Edited 3 time(s). Last edit at 04/19/2015 05:13PM by blakebart.

Hi Blake, it turns out that the original version of Bossac that you can download from the schumatec site doesn't support the processor on the Duet (or the Arduino Due). They have a dev version that looks like it does include the support, but no precompiled binaries for that version. So the simplest option is to install Arduino and pick up Bossac from that. See the instructions here [reprappro.com] for how to install Arduino. Then see here [reprappro.com] for how to flash the firmware (basically the same as on my blog entry), except pick up the firmware binary from my repository (current version is 1.04f).

If you are running Windows, then I could send you just the bossac.exe if you wish, which I think should work with the bossac driver you have already installed. Drop me a PM if you would like this.

It's on my list to build an installable Bossac package including the GUI version from the latest sources, but I haven't managed to build it yet.

[EDIT: I've now updated the instructions for installing bossac in my blog entry.]

HTH David

Edited 2 time(s). Last edit at 04/19/2015 06:10PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Hello David, super thankful for you getting back to me so soon!

Well I just successfully flashed the Duet with your delta firmware. I hadn't seen your post, but for what it's worth, it appears I followed your thinking and I downloaded the Arduino IDE 1.6.1, which contains the bossac executable, collected the bossac application file and your delta firmware binary in one location and used a command line to flash the Duet memory per the instructions here:

[reprappro.com]

The driver provider is Arduino Srl (www.arduino.org), the driver date is 2/27/14 and the version is 1.1.0.0. I noted that the driver's port settings were 9600/8/none/1/none which I left alone and the flash worked. I may try cranking up the port speed but for now I've got a flashed Duet and can continue on.

Your post cleared the next comment up for me:
(My initial effort was using the Bossa program version 1.2.1 but I think the version that was included in the Arduino distribution was earlier. Perhaps the 1.2.1 version was not compatible with the Duet for some reason, or maybe it was just pilot error. Has anyone used the Bossa GUI to perform the flash?)

Thanks and cheers,
Blake

Edited 5 time(s). Last edit at 04/19/2015 07:42PM by blakebart.

David,

One more question: I'm able to connect to the board via Ethernet, but the 8051 transceiver gets really hot regardless of whether I've got an Ethernet cable connected or not...after a few seconds it's downright painful to keep my finger on it. Is that normal?

And the physical Ethernet port has the usual lights lights but they are not active. Is that typical?

Thanks again,
Blake

Glad you got it working, and I apologise for the misinformation on my blog page.

On my boards, the 8051 chip runs warm. It's uncomfortable to keep my finger on it, but not painful. The green light on the Ethernet connector lights up when I connect the board to my Ethernet switch.

I believe the COM port baud rate is irrelevant, because the Duet has a native USB port. The baud rate setting is used when the USB port is connected downstream to a USB-to-serial converter, as on Arduino Mega and similar.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

well i bit the bullet and purchased a duet/duex4 bundle. guess the arduino/ramps will get repurposed sooner then later...

I've just posted a list of resources for the Duet near the bottom of its page on the RepRap wiki, at [reprap.org].

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

bookmarked. i will probably be downloading your firmware when the time comes.

Quote
Freebird01
bookmarked. i will probably be downloading your firmware when the time comes.

Good luck with your build! I run both my Cartesian printer (Ormerod) and my Delta printer (enlarged Mini Kossel) on Duets, and I also use the X4 on the Ormerod. The delta was a breeze to calibrate - the main thing you need is an accurate Z probe. I am still using the original microswitch probe that came with the Mini Kossel kit - which works surprisingly well - but I will be trying out infrared, FSRs and a couple of other things in the near future.

Currently, my fork is the only one that supports delta printers. I am hopeful that RepRapPro will eventually add my delta movement code and the least-squares auto delta calibration to their official release.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

yea one of the items i haven't considered is how to calibrate it. I still need to design up some sort of probe to do this... The pics in that link i posted to my build are only part of it. I have this entire machine drawn up in 3D cad (Solid Edge ST7) so I am amble to have all the stl files to be made in the makerbot as well as any sheet metal flat patterns so i can cut them out on my plasmacam table.

On my delta I use ramps and marlin as a firmware. IMHO there are limitations but not as severe as one might think. I have printed at 150mm/s on my printer and honestly at those speeds the weight of my moving parts was more of a concern than the cpu.

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My Personal Blog. Build blog.
[engineerd3d.ddns.net]

Modicum V1 sold on e-bay user jaguarking11

Is there somewhere online where i can find a 3d cad model of the Duet and Due4x boards? would make it easier to draw up an enclosure for them...

The PCB design files for the Duet are on github, you can get the board size and fixing hole locations from there. But if you are familiar with OpenScad, then I suggest you adapt an existing Duet enclosure design, such as mine here [www.thingiverse.com] or the original one that I remixed it from.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

where on the duet board are you attaching the leads for your z-probe?

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Freebird01
where on the duet board are you attaching the leads for your z-probe?

Best place to connect the IR Zprobe is as shown at [miscsolutions.wordpress.com]. The blue wire is a little awkward because it goes to the expansion connector. In fact I modified one of my Duets to add an extra 3-pin connector at the bottom for the Z probe. My other Duet had the shield on top of it to do multi-extrusion, and the shield provides a separate 4-pin connector for the zprobe.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

my apologies i should have clarified in my earlier question... i am using a limit switch so its only 2 wire. i assume one will follow the blue wire to the expansion connector but does this signal need + or - to work?

If it's just a switch, connect it to the E0 endstop connector, just the same as for the XYZ endstops i.e. the outer 2 connections of the 3. By default, the firmware expects the switch to be close when deployed but not yet triggered.

Edited 1 time(s). Last edit at 06/26/2015 02:17PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].