Marlin Board Selection for Homemade Electronics.

I'm building my own 3D printer form scratch. I'm going to use the Easydriver boards for the steppers, and hook up the various electronics to the Arduino pins. The Marlin firmware allows you to choose the board you are using, and I noticed in the Config file there was a selection for a board "99."

Is this the "board" you would use if you are using homebrew electronics? and if not, is there such a selection?

Ultimately if there isn't such a choice, could I "piggyback" the pin selections from let's say the RAMPS board?

Thanks in Advance!

What I was going to do was just select the RAMPS 1.4 setting, and use the RAMPS Schematic to make sure I connect to the same pins.

NOTE: Within the configuration.h of popular Arduino Frimware, you can easily re-assign pins if you want to.

I thought that was done in the pin.h file?

Yes, you will have to modify the pins.h file.

Are you going to build a board to support the necessary electronics for hotend, heated bed, fan, thermistors and endstops?

Personally, I wouldn't try to re-invent the wheel. A bare RAMPS PCB is cheap enough ~ $10 from ultimachine. Just populate the headers you need and discard the rest.

BUT...

Are you really sure this is something you want to do? First, what stepper motors will you be using? Do you have a spec sheet available? What will they draw? The Easydriver chip (A3967) can only supply 0.75A max. Is this enough for your stepper? If so, great! If not then it's an issue.

I can completely understand wanting to go the homebrew route - making it yourself, from scratch is an awesome accomplishment. I'm just trying to save you money and heartache.

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- akhlut

Just remember - Iterate, Iterate, Iterate!

[myhomelessmind.blogspot.com]

I checked the amperage ratings, and all and they were good.

BUT, i notice you said it would be cheaper to go with a RAMPS board...I was under the impression that it would cost more to buy it than to go the homebrew way?

Honestly all it looks like when ever you buy a board is the Stepper Driver boards, various pin connections, and resistors. (I'm oversimplifying of course.) That being said, I already have the Easydriver boards, and resistors are certainly cheap. lol

I'm most likely missing something???, but it just seems cheaper to build your own electronics.

Maybe in terms of simply throwing it together on a perfboard then yes, a perfboard would be cheaper. But there is also the element of time, and more importantly the cost of errors - unless you are perfect the first time. A lot of the thinking has already been done for you with a RAMPS PCB - you just have to make the appropriate connections.

What are the steppers you have rated at? For instance a common motor used in reprap has specs similar to this:
[ultimachine.com]

That motor could be easily driven to its max torque by this driver [www.sparkfun.com], but not this one [www.sparkfun.com].

I'm not trying to discourage you from going the homebrew route - just trying to give you some perspective.

Sometimes taking the road less traveled is a rewarding experience, but sometimes the road less traveled is less traveled for a reason.

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- akhlut

Just remember - Iterate, Iterate, Iterate!

[myhomelessmind.blogspot.com]

Well, if the perfboard was the choice I was going with, so that's great that you think it'd be the cheapest. XD

And I know there is some risk, but I'm confident I can do it if I take my time...hopefully. Besides I think I'll like the challenge. Granted the RAMPS board does make it easier, but it looks to me as if you'd have to pay for the drivers anyway, and the board with components. All seeming to add up to $120+;(correct me if I'm wrong) more than if I were to use Easydrivers and the minimum components required.

My main thing was just seeing if it IS possible, and trying to foresee any possible road blocks ahead.

My motors are rated at 333mA, well within the range of the regular Easydriver which is rated up to 750mA,btw. The torque seems good too, at least from what the reprap wiki recommends.

I bought a Sanguinololu PCB and a blank Mega1284 and populate it with parts from my part bins, then I hook those Atmega pins to a 4axis TB6560 stepper driver that I already have and drive a CNC machine to print. Was pretty cheap I think

Edited 2 time(s). Last edit at 05/14/2013 01:13AM by ThanhTran.

Now that sounds tempting. I could use the Easydrivers I already have, and use the Sanguinololu. I'll look into that as well. Thanks for the idea!

theruss007 Wrote:
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> Honestly all it looks like when ever you buy a
> board is the Stepper Driver boards, various pin
> connections, and resistors. (I'm oversimplifying
> of course.) That being said, I already have the
> Easydriver boards, and resistors are certainly
> cheap. lol
>
> I'm most likely missing something???, but it just
> seems cheaper to build your own electronics.

RAMPS and other stuff is built in large quantity.

You could attempt to buy the parts individually, but it will cost you a lot more because you'll have to buy at minimum quantities, and shipping from different suppliers.

[www.ultibots.com]

I'd be surprised if anyone could build this entire setup homebrew for <$155.

At least with the Sanguinololu, I am able to get it the cheapest by buying a bare board, and sourcing all the components from Digikey and drivers from Pololu. As for RAMPS, it's a little different because the parts are largely surface mount, unless you build one of the older versions of it.

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ShadowRam Wrote:
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> [www.ultibots.com]
> dle/
>
> I'd be surprised if anyone could build this entire
> setup homebrew for <$155.

at $155 this is not even a very good price. you can find better eg on ebay, while keeping quality stuff

The Sanguinololu kit from Ebay without stepper drivers is $35 with free shipping. The A4988 stepper drivers can be found in the US for $8 each. Of course you can build them for under $155. The only problem is that it takes several late nights after work to build them. If you pay for them, you can use that time to learn the software settings or playing with the prints

[www.automationtechnologiesinc.com]

if this is your first go at 3d printing kit, it would be well worth getting something already assembled. then some of us can help troubleshoot with you and get you up and going.

save the do it your self for the printer build!

It is, indeed my first go. And seeing as how it's a low price on ebay, I think I'll go the Sanguinololu kit route. But I think I'll still try and use the Easydrivers with it, if I can. I just don't won't them to go to waste. XD

Quote

Of course you can build them for under $155. The only problem is that it takes several late nights after work to build them. If you pay for them, you can use that time to learn the software settings or playing with the prints

Exactly. Also, making the controller DIY is simply part of the fun.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

So basically, if I connect the Step, DIr, and Enable pins to the corresponding pins on my Easydrivers, everything should work the same, correct?

Btw, that's the Sanguinololu schematic above.