Closed boelle closed 5 years ago
The BOM:
https://docs.google.com/spreadsheets/d/1RLnmdB46gqgr1EFkkU6c9ktHnhKonsIwyvMgGwauXlQ/edit?usp=sharing
hope it makes sense
will recheck to see if i screwed up on a footprint etc, what could be interesting is if we can get it cheaper and still only buy just what is needed for one board
For the fun out it i uploaded the board files to oshpark and 3 boards cost 77$ thats roughly 22€ so its 87€ for one board without any assembly done
I got €328 for complete BOM quantity 10 at mouser(uk) ... there is a decent price break at x10 but that is quite a difference.
The EEPROM should be < €1, e.g. https://www.mouser.co.uk/ProductDetail/511-M24512-RMN6TP
OSHPark is shockingly expensive compared to Chinese sources. I usually get boards from Itead.
hehe, i agree on oshpark, but they where the only i knew could take the kicad pcb file directly like they do with eagle files
Do you think we can get the parts much cheaper if only going for 1 board at a time? and just the usual crazy thought, how many boards do you think would be needed in a batch before it can compete with the unsafe version allready on sale?
EDIT: the cheaper EEPROM knocked the price for parts down to 60€
Do you think we can get the parts much cheaper if only going for 1 board at a time?
For things like pin strips/header I buy them in bulk off ebay then cut to size. That's ok for DIY, but not for volume manufacture. I also buy smaller connectors off ebay, the quality is good enough. For the main high current power connectors I get from RS, Digikey etc. For resistors,caps,LEDs etc I buy 50 or 100 but I use them in other projects.
There are basically two ways to reduce the unit cost; build a LOT of units or build it in China. At about x1000 the volume discount reduces the BOM cost to about 50%. Manufacturers like Geetech will be buying full reels from local market at wholesale prices, plus they have cheap labor costs. The company I worked for prices parts in x10,000 quantity, and they weren't really a high volume manufacturer. They get parts from distributors like Arrow or direct from manufacturer. To get near to ebay/aliexpress RAMPS-FD prices is basically impossible if manufactured in small quantity, or in the West. I guess a company like Olimex could make it for about 2x ebay price.
I changed the fuse holders to https://www.mouser.co.uk/ProductDetail/Keystone-Electronics/3568?qs=%2fha2pyFaduhjKj2TpGWSG6EII8c9zrvT6dr%2fadQGxMA%3d, they are slightly cheaper than the Littelfuse.
and most important they are better rated, i was a bit worried that the 12A was not enough for things like the bed
EDIT: the fuse holders knocked another 5€ off EDIT2: i just downloaded the 3 hour old copy of the board and i can see that also the reset switch is smd now. will change that tomorrow
and for some odd reason not very much of the 3d shapes show up and some are not rotated right, i guess that the eyecandy side of things would come last
I looked into the current ratings quite a lot. Current ratings are a little fuzzy. e.g. for the fuse holder it has 3 ratings, UL;20A, UR;15A, CSA:10A. They use different test scenarios and come up with different ratings. Those will have some margin built in. Current ratings are thermal ratings, if the component has free movement of air around it will have a higher effective rating than if packed next to others in a closed box. The advantage of branded parts is that you can be sure the part really is made to that rating, so provided you stay within 20% or so it should be fine. OTOH, the chinese knockoffs will rate parts at 15A but they are only good for half that. Note though that Molex etc do the same type of connector with different ratings (due to the type of plastic used). It is tempting to pick a cheaper version but it might have a lower rating.
For those type of connectors, 15A is around the max, to go higher would need a larger connector. 16A seems high for heat bed, thats nearly 200W. At that point it's a whole lot better to use 24V.
@boelle FD V2.1 about $21/pcs
@bobc about the amps, it was me that messed up a bit, the mk42 heat bed is only 12V but ~0.8 ohms so its ~180W, i just remembered it as more than that. Not sure if it would be ok to drive the same bed with 24V
strange enough orballoprinting.com also do a clone of the mk52 bed ( the one with magnetic steel sheets ) and that one should be a 24v one, but their picture say 12V, not sure why
well time for me to get my printer running... getting close to where i want things
final thought, would a V2.2 at arrund the 22 $ mark be more a competitor ? of course we would still need to retain control of the parts used etc
@yyf2009 would it make sense for you to sell the V2.2 instead once the design is finalised? or do you have to many boards in stock
Does it make sense to reconnect power source for heaters and join with the bed ? It is easy tu buy 24V heat bed, 24V 30,40W cartridges. Good fans are 12V only (and 5V), like Sunon Maglev MF50151VX-A99, Noctua NF-A4x20.
Using 24V Power Supply + Step-down 12V 2-3Amp I can make this configuration. Or 24V bed and heaters, 12 step-down fans+etc, 30+ step-up for motors. etc.
@boelle There are 10 pcb v2.2, I have not yet started to assemble, if you complete the design, I can produce, and sell them
@yyf2009 please dont start to assemble them. @bobc have not finished the pcb design
@boelle Do I need to wait for a new design file? , how long it will take?
@yyf2009 i dont know how long it will take for @bobc to finish and release V2.2
if you look here: https://github.com/bobc/RAMPS-FD/tree/dev
it clearly says that nothing is ready for release yet, so the 10 boards you have is a waste
where did you get your v2.2 design files from?
@boelle from bobc
but @bobc has not relased the files yet
do you have a link to where you got them?
@yyf2009
you have not read this file: https://github.com/bobc/RAMPS-FD/blob/dev/README.md
Sorry, I forgot to update the readme when I last worked on the dev version.
I don't have any plan to update 2.2 in the foreseeable future, so the current dev version is as good as any. Of course, now that people are building "2.2" even though it has not been released or even finished (deja vu), I would have to call the next iteration 2.3...
@bobc i just told our friend from china that updates could happen and that just because the files are there it does not mean they are good for production
ie i wanted to prevent that we have a repeat of what a other well know china company did with the first unsafe version
What do people think of https://reprap.org/wiki/RD3D/1.0 ?
looking, it smells a bit like the source is your board
It's based on RAMPS 1.4.2 which was done by German RepRap. It probably works out cheaper than RAMPS-FD.
the thing i'm concerned about is if the board layout is done right when it comes to current etc. and that analog stuff is isolated from the digital so noise does not go from one side to the other
and then if the prober parts are used
There is also https://github.com/dvjcodec/Due3Dom, which is the Polish board mentioned earlier, but it is not Open Source. But there might be some ideas there, the layout is much cleaner but the board is quite big...
There is also DUE3DOM mini and DUE3DOM LE. As far as I know all three boards has source on github.
"Has source" is not the same as "Open Source"! It's only Open Source if it has an open source license, and CC-BY-NC is not Open Source.
I didn't find a DUE3DOM LE on github.
@bobc what is your own stand on the RD3D board?
RD3D has a few features more than RAMPS-FD, e.g. onboard SD and support for SPI steppers, otherwise it seems similar. The designer seems to have ignored RAMPS-FD, not sure why. The board was costed at $15/100 (Chinese production), but little activity for a while.
hmm... i could live without the SD and SPI, but also i'm not scared soldering wires on the adapter for the display etc
but if you at some point add that to v2.2 or 2.3 i would go for that and assemble a board myself
with all the work and experience that have been put in to Ramps FD it would be a shame to throw it out the window
Just a thought that hit me last night...
i know there might be a price difference, but would the Teensy 3.6 be a better board than the due?
have played a bit with the thought on the schematics... since Teensy is 3.3v only a few things can be removed.
I started out with the power schematic, does this look about right?
I wonder for the VCC rail, what is the draw on that? the Teensy have 250 mA on its 3.3V output if the draw is below that we could simply make the VCC rail use that
EDIT: i looked at the emergency stop sheet where the buffers are and read datasheets on them. If not mistaken they need 5V to run, but i cant see where power is connected to them?
EDIT2: ahh, i clicked show hidden pins and they came up.
check my logic here for the emergency stop sheet
since the teensy is not 5v tolerant rp2 and rp3 needs to be connected to 3.3V but the buffers themselfes needs to be connected to 5v. or is there no need to change anything?
@bobc would it be easy for you to adjust the design to fit on the Teensy? i have given it some more thought and i think it could be an great option.
Sadly i lack the skills to do this 100% on my own
I wouldn't favour Teensy as they are not Open Source. Anyway, they don't really have enough pins.
oh well.... the lack of pins makes the difference
do you have any work not pushed to github? i'm going to finish my hybercube next month and want to use Ramps FD and need to plan a bit ahead so i can order parts etc
@bobc
did you make the changes to allow for tmc2130? if so are they pushed to github so we all can have a look?
i will spend the day going over the BOM i made up and start prep work to order parts. I will order enough parts for at least 3 boards so i have spares, but my plan is to make 2 boards so i can fit them on both my machines
do you have any work not pushed to github?
I started a change to make the aux connectors plug directly to an LCD panel instead of needing an adapter board, but I don't have time to finish it.
did you make the changes to allow for tmc2130? if so are they pushed to github so we all can have a look?
I updated the schematic to add some jumpers and pull up resistors on SLEEP/RESET. I added the resistors to the pcb and routing the traces. Those changes are in github,
BUT I did not place the jumpers, it would take a complete re-routing to fit them in, probably need to increase board size. Since then I noticed a smarter way to do the jumpers from another project, but again I don't have time to do any of that.
It seems in some places TMC2130 are not regarded highly, I have never used them so couldn't give an opinion.
The problem with 2130 is that they run more hot. And they do require 24V to be silent. Some people dont know that they can feed them 24V by removing the Vmot pin and connect it to an 24V source
and then of course there is the lot of misinformation and china knockoff's that dont help it either.
If it was me i would go for the TMC2208 instead, it runs cooler and can handle more current, but it requires 2 serial lines. But maybe 2 serial lines are more easy to do than SPI.
So what you have pushed so far on https://github.com/bobc/RAMPS-FD/tree/dev/RAMPS-FD seems to be ok for me, i dont mind running a few "bodge" wires to make it work as it can be done quite nicely if i take my time
@boelle
@bobc
so to this day is the branch of main (v2.1/V2.2?) or dev (v2.2/2.3?) are ready to use?
I would like to find a pre-build RAMPS-FD v2.1 form @yyf2009, but the shipping cost is too irrational.
so I'm trying to find other alternatives, it's good to see you guys are here thu.
BTY: A page in Reprap shows a retired man call MrAlvin are beginning his work to design RAMPS 1.7 where is the post in discussion https://reprap.org/forum/read.php?219,824661
they seem to have some interesting idea about jumper's layout to support TMC2130s
@craftoscar
no @bobc has not released v 2.2 as ready for production, not sure about v 2.1
I am shure @yyf2009 had some v2.1 ver.B in his hand. and I welling to purchese it excpt for the shipping fees I notice that a guy in Poland are selling? v2.2 PCBs
by pic it caps 6 MOS so that probbly had onbord 5V MOS intergated. like @bobc mentioned in post years ago to his vision in Ver 2.3
by the soure in https://github.com/bobc/RAMPS-FD/tree/dev/RAMPS-FD I visit in June 18 here (GMT+8) in Taiwan
shows the mark on PCB is v2.3 now it share the simmlar layout with the Polish site
For alternative I like to make one for myself thats a bit confusing
I need to know witch one are clear to go
if any one want to get together to mess produce the PCBs I would like to join!
the reson why took me here is that I just fried my MKS Gen L in last thermocouple test My intention is to use some Analogue instrument AMP (like AD595/597/8495) as Temp sensor to print Poly Carbonate. but I had some hard time to find the geinume schemeatics form MKS to tinkiering it And the expriance to hock their MKS TFT32 touch screen just suck.
So I start to find open source boards and RepRap page lead me here.
non of them are clear to go.... as said before they are not ready for production.
I got it, I thought that @bobc are still fine tuning V2.3 now I am really looking foward to this borad, since it already cumalated lot of improvemnts. I think this borad deserve more popularty, and I would like to made some for my frinds new in 3D printing, or possibly my 2nd printer in future .
To me the V2.1 s are good to go,In conditioning for instrumental AMP for thermocouples (yeah they'er very sensitive to voltage referance)
yep he is doing that, but it will take a long time.
I'm also looking for new electronics for my 2 printers and i'm very tempted to use v2.2 from https://github.com/bobc/RAMPS-FD/tree/dev/RAMPS-FD
both v2.1 and 2.2 are just versions. I think @bobc increase versions when a step is made. It does not mean its good to go, so we are making board at our own risk.
@craftoscar
btw.... if you have not read it, the reason why Ramps FD have a bad name stuck to it is because some factories took the very first versions and mass produced it. A lot of people got boards that was not safe and people risked burning down their house.
and a lot has happended since.
to give Ramps FD a good name again it must be updated and tested. and if it should be able to to compete it must be same price as what you can get on ebay
but to make that happen we need a factory we can trust and they must use only good parts that we can give green light on
but again @bobc has a lot of other things to do and i think Ramps FD is not a big thing for him
So we will need a lot of patience, if i remember correct he is trying to add support for TMC2130 and that requires a lot of work. And there are a few other things i forgot that he is also working on
@boelle
btw.... if you have not read it, the reason why Ramps FD have a bad name stuck to it is because some factories took the very first versions and mass produced it.
I knew, I had read thoes post pepole use Geeetech 3D based v1s...
to give Ramps FD a good name again it must be updated and tested. and if it should be able to to compete it must be same price as what you can get on ebay
but to make that happen we need a factory we can trust and they must use only good parts that we can give green light on
but again @bobc has a lot of other things to do and i think Ramps FD is not a big thing for him
Yes, there sure have some fab are will cabable and good QC bulid in As a Taiwanese live aside China, I know OEM are the main foruse in this region but things goes to OEM qunatity DO maters. We Taiwanese likes to hosts small production (maybe 100~ frew k pce.) for some costomize gadgets looks like kickstarter, but mostly designer already had good working prototypes aside their intention is to make their product commercialize, ro perhase make a new company themselfs
witch is quite diffent aspect then 3D printer electronics here we are
And to 3D printer electronics, Dozen of company based in China already develop their own feature rich 32 bit contrl boards in very resonable price (even the borads like Maga+RAMPS1.4 or Due+RAMPS-fd can't compete with.) But problem is that the support are not good enought for costomer ouside China And documentation are insufissent for us to tinkering or Mod around it. To make mod working u may need to buy their upgrad moudels (witch normally 1/3 about their MB prise). I not bleam them about the price, this are their working business mode. but to me some of their moudels are really over priced and you can't really find how they worked when it fail.
To make me simple I just want to find prize reasonable, simple ,easy to fix electronic to work with
So we will need a lot of patience, if i remember correct he is trying to add support for TMC2130 and that requires a lot of work. And there are a few other things i forgot that he is also working on
To TMC2130 I not very look forward to it too much (at least for high performance or big volume printers) the low current output and thermal problem keep me away from it. I will be held to see if Trinamic will change their interface to another one like they done in TMC2208 but AFAIK their possible next-gen stepstick (TMC-5160 according to a post on the twitt) probably will stick on SPI
as per subject would it make sense to update Ramps FD ? are there any improvements that could be made?