Anyone tried to make a 3D Printer controller?

Sooo some good and bad news about the Hardware:

First of all, the good one: Almost everything has arrived Only waiting for the fuse holder and the angled connectors. Guess they will arrive next week.

Another one: IT WORKS Tried a fast and dirty blink test, and well, it blinks Im really glad it turned out to work. Maybe i will upload a small video of it.

Ok, now some bad ones:

-The Resistors for the 3.3V Buck converter arent the best. Since i didnt paid any attention on how precise they are, i have to pay bit more so i can get them locally. seems like these 5% ones make a shift of about +150mV = 3.45V. So i will try to get them locally.

-As for now, it seems like every connection on the Mainboard is there, buut on the SD Card one ground reference is gone. It was in the gerber files, but seems like i didnt met their capabilities, so they simply removed it. because of that, the Power LED on the SD Module isnt working. The ground reference for the additional output module is also missing on 3 of the 4 outputs. But the Heater and Heatbed modules seem to be fine. tried them, and they work. The Ground reference of the sd card has also been removed. so its worthless, aswell as the additional module (unless you want to use some jumpers)

-The heater/heatbed LED is inversed. So i have to change their connection aswell.

-I totally forgot to add some 12V/5V/3V3 LEDs on the mainboard. So they have to be added.

-And for some reason the mounting holes on the mainboard are gone. either I didnt saved it or removed it because of a github pull. Could bet i posted a picture of them somewhere.

-Some of the silkscreening is not correct. As far as i have noticed: The Caps of the 5V regulator have to be the other way around. The 3V3 Diode has to be the other way around. Most of the LEDS also have wrong Silkscreening. Not sure how it happened with the leds. But the caps are most definatly because i still used normal ones in the schematic and then assigned a polarised cap footprint.

-And there arent any dots for IC alignment. That also has to be changed.

-and i forgot most of the better silkscreening. Things like Pin Names, Voltage Pinouts, Boot selection, Voltage selection, Driver Microstepping etc. isnt silkscreened. my fault.

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TL;DR: It works. but there are still some minor mistakes, which can, for the time being, fixed with two or three jumpers.

I will post some pictures as soon as the last parts have arrived.

~Straw

@Straw

I don’t think you have many errors for a complex board.

Mistakes always happen, and we just have to learn by them.

My first simple board using KiCad, may be totally useless, as I didn’t export the solder mask

The issue with the missing track on the SD, highlights the issue with DRC in KiCad.
This is one good thing about Eagle, as companies like DirtyPCB, have made Eagle DCR files.

I really should have tried to use the Eagle DRC somehow with KiCad ( I will need to find a converter), but as my board was mainly Not SMD, i hoped I could just use the default KiCad DRC.

It sounds like you needed DRC settings from elecrow to avoid the problem with the missing track

@RogerClark
yeah, and luckily, they arent really major problems. could have been worse , Imagine the buck converter AND the mcu to let off some magical, sparkly smoke

They have a really in depth spec list, but i might havent imported everything correctly into kicad. i can remember setting up some design rules and using the drc tool, but it seems like i didnt managed to add everything. And IIRC the DRC from eagle is far more customizable than the drc of kicad. Definatly too less options. Or maybe there are some hidden options which i havent found.
Another way of fixing it would be to reduce the seperation distance of the ground layer, but they would just reduce it anyway.
Soo, spacing things out a little bit? seems fair enough.

Oh, one more thing: the Heatbed smd pads are all still for 1206. Soldering a 0805 part into there wasnt really a problem, but it kinda looks out of place

Off for today

~Straw

odds are if you go back and re-examine the board, turn it 90 degrees and again examine it; they’ll be some more.
repeat the above, get a couple of other people to do the same and you’ll all still miss one.

way too many QA reviews, design reviews, software reviews etc etc

stephen

Had nothing to do today, so i ended up with this

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Link

~Straw

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For some reason, this seems to be too big. Another idea would be to make the modules stack on top of the mainboard, which would be really neat, but i would have to redo most of the stuff. so guess thats a task while working on the marlin port, i guess? And ive got to search for a smaller fuse holder, something for like a mini atc fuse instead of the regular one.

As soon as the fuse holders are there, i would be ready to ship out some packs. So if anybody wants.

~Straw

The comnectors on the daughterboards take a lot of space

Just build the modules as part if the main board.

If people dont want those features, they dont need build the sections of the board.
( This is common on many commercial boards. I often see boards where sections are empty of components)

Or.

If board area is an issue, you would need to stack another board completely over the top of the main board.

Personally, I find connectors are always a problem, on the edges of boards.

Hi

I fear that this board is too big. The external molules do not like and I occupy too much space.
The SD module may be removed and added the connectors to a display (display, encoders and SD)
http://reprap.org/wiki/RepRapDiscount_Smart_Controller
or
http://reprap.org/wiki/RepRapDiscount_F … Controller

Everything else, would better to make an expansion borad to be connected above (or below) in arduino style

drk

I’ve used ST32F4xx boards from Waveshare… development, eval, protyping. Pretty good.

http://www.waveshare.com/product.htm

OK, seemed like i didnt really noticed that i have to mirror the pinout on the module side, which means they have to be stacked on top (like a shield) but still hanging outside. I will definatly work on making it more of a mini arduino shield style. so that you just stack the modules ontop of the main board. my bad that i didnt did it the first time, he. But still, gotta find a mini blade fuse holder, or else just go back to glass fuses.

so yeah, there is going to be much rework in the pcbs, but still, they seem to be working for the marlin port.

I also took a small look into the due marlin code, and it mostly seems to be rework in fastio to use the low level stm32 stuff. but correct me on that one .

Drake, that was also the idea why there are two sets of connectors, but i dont think they are directly pin compatible with the reprap controller, especially because it uses a level converter onboard, which would mean to make a board which converts the 3V3 logic from the MCU to 5V logic or just directly a new lcd. Could also be interesting for full color lcds.

~Straw

Hi Straw

I used this old abandoned project, but do not know if this is a start to watch:
https://github.com/MakerLabMe/Marlin_STM32
We consider that it is based on a prehistoric version of Marlin

On my RAMPS FD (for Arduino DUE), I use this converter :

http://it.aliexpress.com/item/3D-printe … 20133.html

That adapter is a bit pricy imo. maybe i manage to do something similar myself and put it onto the next board.

Fuse things: I finally found the fuse holders on farnell. I tried to avoid farnell, digikey etc. because the shipping was too high, but i didnt know farnell has free shipping to germany. Guess i get some of them (and throw a pi3 in there, its 30€ only ^^ ).

For the board connection: Yeah, something like mini shields would be a good idea. Stacking the board vertically seems better than horizontally. Using male smd headers on the “shields” and normal through hole female headers on the mainboard.

i will also try to remake the mainboard, maybe get a different footprint oscillator on there. and definatly rework the 12V rail, looking for max. 5°C temperature rise on the traces.

~Straw

Hi @strawberrymaker

I am picking up work on Marlin/32 again, with a bit of luck it will make it into Marlin mainstream this time. I would quite like to include an STM32 board as one of the supported HAL targets.

So I was wondering how you are getting on with firmware, and maybe we can get an STM32 version into Marlin?

@bobc it should be possible to include it to marlin4due. it seems like it only needs some changes in one file. so it would be easy to add some precompiler arguments and the fitting pinout file.
but because wurstnase stopped on marlin4due, it would maybe be better to take the current marlin rc4, take the changes from marlin4due and add the precompiler parts to the fastio file so it can be used for due and stm32 (or just stm32).

~straw

This project ain’t gonna die now! SMD Pinheaders are really a great thing.

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~Straw

those headers shown are PTH

unfortunately SMD headers, at least the 1 and 2 row ones i have/or seen are somewhat wider as the pins bend outward either for each side for 2 row and alternately for single row.
for the single row( servo?? triples), you can at least pack them slightly more densely as the middle pin will fit between the outer pads of the adjacent one.

stephen

They are PTH on the mainboard for a bit more mechanical strength but smd on the modules aswell as the microstepping selectors. Not sure if laying smd pads next to each other is good, will be a hell to solder.

But this layout wont work anyway, way too much trouble routing the lcd connector. So that is goingm to change.

Ok, basically the main things are done, PCB should also be capable of being manufactured on a 1 ounce board = a loooot cheaper
Hardware wise there hasnt anything changed since the first RC, only the 3V supply is now much smaller, cheaper but not replacable and some much smaller Mini Car fuses. Also now a reverse polarity fuse for the 12V Lines. But i will have to add some resettable fuses for 5V and 3V3 later.

I will just dump some pictures of everything.

Mainboard
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Heatbed Module
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Heater Module
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Stepper Module
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Additional Output Module
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Still gotta rework the SD Card and got to create an adapter to use the reprapdiscount lcds.

~Straw

Looking good.. almost good enough for me to throw some money at it. Roughly how much do you think the BOM will come to?

Thanks
Parts and PCB should be around 35€ maxed out .
But not sure how i will handle assembly. I already looked at some smd vacuums, making them ma
nually should do the job for now.
~Straw