Smoothie, Brainwave or arduino mega 2560, (Mini Kossel)

Im fairly new to reprap and im building a mini kossel. the frame parts are on the way and im building a BOM for the rest (hard sin him in canada and him getting screwed with the shipping price from us hahaha) but I need help choosing the electronics :

All option cost around 120$ if I add 4 drivers to the arduino2560, so wich one should I use and why ?

Thanks

Advice about arduino2560 clone for 15 $ ?

Hi,
I assume you mean the usual Arduino Mega 2560 + RAMPS 1.4 + Pololu-style drivers when you write "arduino2560".

At the risk of being hanged for blasphemy, I would advise you to just buy the following inexpensive electronics:

Arduino Mega 2560 clone: $ 10
Ramps 1.4 clone: $ 7
5 x DRV8825 drivers (clones): $10 (yes, one extra, they come in 5 anyways)
2004 LCD smart controller (clone): $ 12
80mm fan: $ 2

Grand total: $ 41. If you by any chance damage any component during the assembly, you won't be out by more than $10 or so.



Also buy a Raspberry Pi 2 (quad core) and a wifi dongle and 5V 2A supply: $55 or so. Use the RPi2 as a Wi-Fi accessible OctoPrint server.

OctoGoatBox

Enjoy your build and your mini Kossel when it's up and running!

Good luck!

The Google Deltabots group 25% off coupon code for Smoothieboards and accessories is good until the end of the month, and can be redeemed at either their USA or France distributors. Uberclock (USA distributor) is allegedly shut down for a week while they attend a maker festival, but it doesn't sound like you are in a pressing need to have a board in hand this week.

Many Delta owners are fans of Smoothieware, since the 32-bit architecture is not stressed with Delta math and the software is much easier to configure than 8-bit Arduino-based solutions like the Mega2560/RAMPS.....

Thanks !
Since im on a budget I will go for the arduino/ramp clone from SainSmart, 2 years waranty and free shipping to canada. (just the shiping for the real arduino would cost me more then the clone full price)

But they only have A4988 drivers wich I think only do 16 stepping insted of 32 ? So i would be better buying DRV8825 right ?

Comparison A4988 vs DRV8825 here: [reprap.org]

The Arduino Mega is short of CPU power for driving a delta, so getting it working involves some serious compromises and tweaking, as you see if you read other posts in this forum. My advice is to use something more powerful. My preference is for Duet electronics, although I am biased because I added the delta support to the firmware for it. See the link in my signature for more.

---

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].

How much is a duet ? I went back to being a student so im kinda poor right now.

I've seen the result of this change " DELTA_SEGMENTS_PER_SECOND to 80 insted of 200" in another post and it gave me hight hope of being able to live with a ramp for a couple month. I could invest the savings in a ed3 hotend. (107 $ ouch)

Next to what to do with for the bowten.

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Lerathel
But they only have A4988 drivers wich I think only do 16 stepping insted of 32 ? So i would be better buying DRV8825 right ?

Has anyone successfully run a Delta at speed with DRV8825's and 1/32 stepping on an 8-bit controller? Seems like a bad idea, doubling the math from running the steppers at twice their resolution.....

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Lerathel
How much is a duet ? I went back to being a student so im kinda poor right now.

Cheapest price at present I think is GBP65 + shipping + tax (if applicable) from Think3DPrint3D, which is quite a bit less than the Smoothieboard. It has four A4982 stepper drivers on board along with software control of stepper motor currents, native USB, Ethernet, and SDHC card socket. So it is a whole it better than Arduino/RAMPS. Just take care not to connect./disconnect stepper motors with power applied, because if you blow one of the stepper drivers, you need to either replace the whole board or do some tricky SMD rework (the same goes for other boards that have the drivers built-in).

A lower-cost option that still has a lot more processing power than the Arduino Mega is the AZSMZ Mini. AFAIR it has plug-in drivers like RAMPS and runs Smoothieware, but it doesn't have the Ethernet port or software control of stepper motor current. I have no experience of it.

---

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].

The only issue I have ever had running a delta on a Mega 2560, RAMPS, A4988 combo is when I tried to also run a 128x64 full graphics LCD display. I now use a reprap discount 4 line display and run at 100mm/s and 200 delta segments. Never had an issue with lack of processor oomf. I don't see what benefit I would get from a 32bit controller. If I wanted to connect via Ethernet I would add a RasPi and Octoprint (I don't BTW). Wow. How controversial is that?

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vreihen

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Lerathel
But they only have A4988 drivers wich I think only do 16 stepping insted of 32 ? So i would be better buying DRV8825 right ?

Has anyone successfully run a Delta at speed with DRV8825's and 1/32 stepping on an 8-bit controller? Seems like a bad idea, doubling the math from running the steppers at twice their resolution.....

I am not so sure the math is doubled, from a quick look at the code in Marlin it seems to me that the interval between step pulses is halved when going from 1/16th to 1/32th microstepping, but the amount of calculations per second (i.e. what you seem to call "the math") is really determined by DELTA_SEGMENTS_PER_SECOND.

thanks for all the anwser, I ordered and arduino clone with the same chips as the original, a ramp 1.4 and 4 dvr8825 with heatsink. 30 US, 41 canadian $, thats nice.

I saw some nice aluminium molded part but they are so expensive ouch, not for me haha.

[www.aliexpress.com]

100$ just for the 3 botom parts ! Must really stabilise the frame !

Edited 1 time(s). Last edit at 03/18/2015 11:19AM by Lerathel.

Oh and do I really need an lcd screen for the printer ? I plan to let it alway connected to my computer so what's the use ?

The LCD is optional in your case, and you can always add it at a later stage, after you get your printer working and calibrated. In any case, it's a low cost item, that is why many people buy it right from the start. Since it has an integrated SD card reader, it frees your PC for other uses.

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Lerathel
I saw some nice aluminium molded part but they are so expensive ouch, not for me haha.

[www.aliexpress.com]

100$ just for the 3 botom parts ! Must be really stabilise the frame !

The link that you posted includes both top and bottom brackets for $100. Given that I dropped $300+ last month with Misumi to build an all-metal frame for my next printer, those brackets look like a bargain to me. (My latest design goal is to build a printer that I can throw against the wall, use to hold up a car engine block, and still print without needing to be re-calibrated.)

Every vendor of printer parts should be required to have a disclaimer that building 3D printers can turn from a hobby into an obsession when you're not looking. Printed parts are fine for your first printer to get you hooked, but after a year and three more printers you will realize that they are holding you back in the speed and print quality department.....

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AndrewBCN
The LCD is optional in your case, and you can always add it at a later stage, after you get your printer working and calibrated. In any case, it's a low cost item, that is why many people buy it right from the start. Since it has an integrated SD card reader, it frees your PC for other uses.

The LCD may be optional, but unless you accept either a low printing speed or stop/start printing while the USB struggles to catch up with the printer, the SD card socket isn't. That's another reason why I think the Mega/RAMPS is a poor choice as a 3D printer controller these days. The more modern boards mostly have native (higher speed) USB and an SD card slot built in. They also have adequate 5V regulators that don't fail at the slightest provocation. I could go on...

---

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].

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dc42

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AndrewBCN
The LCD is optional in your case, and you can always add it at a later stage, after you get your printer working and calibrated. In any case, it's a low cost item, that is why many people buy it right from the start. Since it has an integrated SD card reader, it frees your PC for other uses.

The LCD may be optional, but unless you accept either a low printing speed or stop/start printing while the USB struggles to catch up with the printer, the SD card socket isn't. That's another reason why I think the Mega/RAMPS is a poor choice as a 3D printer controller these days. The more modern boards mostly have native (higher speed) USB and an SD card slot built in. They also have adequate 5V regulators that don't fail at the slightest provocation. I could go on...

Again, is that from your experience or just hearsay? My experience is that the Arduino Mega 2560 + RAMPS 1.4 + Pololu-style drivers (ultra-inexpensive Made in China clones) that I have used up until now work fine when connected to my OctoGoatBox at baud rates of 250 000 (Marlin's default) and I have not noticed any slow down due to serial communications. Personally I don't use the SD card reader at all since the OctoGoatBox is much more practical as a storage device for g-code files.

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AndrewBCN

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dc42

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AndrewBCN
The LCD is optional in your case, and you can always add it at a later stage, after you get your printer working and calibrated. In any case, it's a low cost item, that is why many people buy it right from the start. Since it has an integrated SD card reader, it frees your PC for other uses.

The LCD may be optional, but unless you accept either a low printing speed or stop/start printing while the USB struggles to catch up with the printer, the SD card socket isn't. That's another reason why I think the Mega/RAMPS is a poor choice as a 3D printer controller these days. The more modern boards mostly have native (higher speed) USB and an SD card slot built in. They also have adequate 5V regulators that don't fail at the slightest provocation. I could go on...

Again, is that from your experience or just hearsay? My experience is that the Arduino Mega 2560 + RAMPS 1.4 + Pololu-style drivers (ultra-inexpensive Made in China clones) that I have used up until now work fine when connected to my OctoGoatBox at baud rates of 250 000 (Marlin's default) and I have not noticed any slow down due to serial communications. Personally I don't use the SD card reader at all since the OctoGoatBox is much more practical as a storage device for g-code files.

It's from experience (using Pronterface to print gcode files over USB ), and from reading other user's experiences on these forums. Part of the problem is that the serial-over-USB interface used by the Mega has no flow control. This means that every time Pronterface sends a command to it, it has to wait for the "OK" response so that it knows it is safe to send another command without the receive buffer overflowing. See [reprap.org]. When using a board with native USB, flow control is built in to the USB protocol, so Pronterface doesn't need to wait for the "OK" response.

I guess it's possible that OctoGoat is faster than Pronterface at dealing with the received OK messages, so your setup may handle higher printer speeds than Pronterface does. Nevertheless, I would be interested in knowing whether you are able to move the print head in a series of circles, say about 30mm diameter formed from 100 or more line segments, at 60mm/sec or greater without slowing down.

---

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].

You're right, its top and bottom make it more interesting, sadly its for 2020 and I did not find an affordable source of 2020 extrusion in canada, I even saw a 10 $ extrusion on ebay costing 163$ shipping to canada... So sad that it cost me 10x more in shiping from us to canada then china to canada, this is ridiculous...


So I went for 1515 like those(bellow) wich seem to have more metal then the open beam so I wish they are a little bit stronger and will do a good job.


Im trying to find the printed parts, I heard that you can receive some free if you give 2 set to the community once the printer is all set. seem interesting.

I will upgrade eventualy to a better board solution once I get the hang of 3d printer, its will be my first 3d printer and the first one I build and I need to save money.

Edited 3 time(s). Last edit at 03/18/2015 11:43AM by Lerathel.

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dc42
The LCD may be optional, but unless you accept either a low printing speed or stop/start printing while the USB struggles to catch up with the printer, the SD card socket isn't. That's another reason why I think the Mega/RAMPS is a poor choice as a 3D printer controller these days. The more modern boards mostly have native (higher speed) USB and an SD card slot built in. They also have adequate 5V regulators that don't fail at the slightest provocation. I could go on...

Depends on what you call "low speed". I print at 60mm/s all day long via Repetier Host / firmware, with no unexpected pauses, via USB... and since I'm doing it under linux, I'm running at 115200 baud instead of 250000. Also running at 180 segments/s for print, 70 segments/s for travel.

I recently realized that my SD card reader is un-usable at the moment because I didn't get it lined up properly when I built the printer in May last year. Kind of embarrassing, really.

I do use the LCD for status monitoring and tweaking during printing (changing temperature during prints, changing fan speeds) or for homing the printer, etc.. So the LCD interface is very helpful, even though I'm using a host for printing.

Ok I brought a 4x20 lcd and a separate mini-sd card reader for almost nothing. It will be usefull im sure. Thanks !

Edited 1 time(s). Last edit at 03/19/2015 02:06AM by Lerathel.