Making a 3D printer workshop - Electronics

[James Newton]

Took a quick look at the Gen 7 board page on the reprap wiki:
http://reprap.org/wiki/Gen7_Board_1.3.1 
I was wrong at the meeting (the multi color picture threw me off); that IS a single sided board, and designed with large traces and spaces so it could be isolation milled or etched pretty easily. We may be able to just etch a batch of them ourselves without much trouble. First step is finding some cheap single sided copper clad.. 

Do we want to include milling or etching the PCB as another session of the workshop?

At the same time, it would be a good idea to look at the BOM and figure out if there is a point to doing a bulk buy. Sadly, the link to a shopping cart on Mouser from the wiki page doesn't work. I've started building a new one, but I don't want to waste my time if it isn't going to work. Can someone please click on this link, and verify that it puts  the correct components down to L1 into your cart? 

http://www.mouser.com:80/ProjectManager/ProjectDetail.aspx?AccessID=2e6af3da36 

[Jeremie Santos]

The thing about etching, is the time it'll take to drill out the pcb before or after the etching process, and we cant garuntee that the students attending will have it all drilled out prior to the next class where we'll solder everything togetherThe milling seems like it'll be a standard class they'll teach there for that machine.  

The link works, i can see the BOM you've created thus far.

[James Newton]

Very true Jeremy, but on the other had, you can etch a whole batch of boards at once, and you can drill several at a time, but you can only isolation mill one at a time... and even a simple board takes time. That one is going to take a while. 

Maybe we can do ONE in the workshop and then the others can do their on their own time?

Or we can etch one and mill one and then let people do what they want.

Thanks for checking the link. I'll continue as time allows and also swap out some components for ones that are more likely to have a quantity discount at a lower quantity. E.g. the resistors he is using are cut tape, so you don't get a break until you buy thousands.

--

James.

[James Newton]

So I got caught up in it and finished the parts list on Mouser. As far as I can tell, a one off order is between $30 and $50 depending on if you include the spool of wire. If you include ONE spool of wire (more than enough) the X10 order would be about $25 each. That is before doing anything to improve the quantity breaks on the components where he spec'd the tape reel versions. If we had 10 people sign up, it would probably be worth doing a batch order.

Jeremy, or anyone, if you could check over my work and let me know if I screwed anything up? The female headers are 9 vs 8 because the next part down is apparently the same thing but listed separately. And if you can find better alternatives... I think those headers are overpriced, as are the 0.1uF caps. Do those really need to be 50 volt?

Anyway, I've spent far too much time on this already for today.

--

James.

[James Newton]

And I just realized I'm misspelling your name, Jeremie. Sorry!

[Jeremie Santos]

Hey James,

Can you provide the updated link, i don't think the previous link provided is updated to the full list

thanks

-Jeremie

[James Newton]

To the project list on Mouser? It's the one at the top of this thread:

http://www.mouser.com:80/Proje​ctManager/ProjectDetail.aspx?​AccessID=2e6af3da36  

On the wiki, it's the /second/ link at the bottom of the parts list:
http://reprap.org/wiki/Gen7_Board_1.3.1#Electronic_Components  

The one that says "Updated...."

If you aren't seeing the complete list... I don't know... try refreshing your browser window?

--

James.

[James Newton]

So, I've been talking to Markus Hitter from Germany who is the guy who did the board layout for the Gen 7 electronics. He wants to sell kits of the PCBs with all the parts and the cost varies from $73 each for one down to $54 each for 10. $60 each for 5. That is for all the components in both tables on the wiki page, but NOT including the endstop PCBs. He will also sell the PCBs for between $25 and $20 depending on quantity. All of that is including shipping price from Germany. He will take paypal, direct, but I'm working with him on making a shopping cart so his presentation to US customers will be a little more acceptable. Just wanted to let you know. 

So we can either include making the PCB as part of the workshop or just buy it. Honestly, I think most people would just like the electronics part of the build to "go away" LOL... so I question including the making of the PCB. Some people are probably interested in how to make one, but I think that might be better as a separate workshop. That's just my opinion. It can work either way.

If I can find the time, I'm also going to look at having the PCB professionally produced. I'm not sure, but I think it could be less than $20 each even in very small quantities. And a professional PCB is SO much nicer to solder or repair if needed.

I'm sort of starting to loose interest in this based on the lack of feedback from anyone other than Jeremie. If there anyone out there? LOL... Speak up so we know you are still involved!

[Richard Rouse]

Hi James,

This is awesome, I am interested in this board since then you don't
need to buy an expensive arduino mega. Its really cool but I have 4
RAMPS kits already.

I think customers want preassembled boards (that's what ultimachine
says). So would be keen on helping automating fabrication if there's
interest. Maybe could do at this makerplace

Not sure what is going on with this group ... seems like no notices
for meetings been busy last couple of weeks but would be interested in
going next meeting.

Richard

--
Richard Rouse
HTS Resources, LLC.
325 W. Washington St. #2-150
San Diego, CA 92103 USA
619-846-8291
rjdr...@htsresources.com
www.htsresources.com

[James Newton]

Hi Richard, glad to hear from someone. 

Markus and I have continued talking about the Gen7 electronics, tossing ideas back and forth. He is about to release a version 1.4 board and wants to switch to the TB6560 driver which would save some more money over the Polulu boards and provide more drive capacity. The TB6560 has a horrible flaw,
http://www.cnczone.com/forums/stepper_motors_drives/139306-how_can_any_tb6560_driver.html 
but he is working around it by limiting the power supply options to ATX only and using the standby power for logic before switching on the +12 supply, or by including a separate motor supply switch. 

At this point, based on the lack of interest here, and the limited interest on the forum at Makerplace (and the fact that you must be a paying member to post on that forum), and no contact from John about the class he was talking about offering, I'm going to step back and concentrate on other projects. 

If John or you or anyone else asks, I'll be happy to answer questions or do whatever I can to help, but otherwise, I think I've done all that is worth doing at this point. Hopefully interest will grow in the future.

--

James.

[Richard Rouse]

Yeah, I am sort in the dark now too about this.

Its great there is a hackerspace but if they do not have a free open
meeting session then it sucks.

We had one meeting in my lab and it was awesome but the second meeting
the group totally flaked out on me so I said screw it.

Makerplace should have a open hour or so. Nuecleon was willing on
having this on Saturdays. Its sort of far though.

Richard

[James Newton]

The problem with Makerplace (I assume you mean makerplace.com, the facility that opened in San Diego on Morena?) is that you have to commit better than $100 per month ($135 seems to be the current best price) to join before you can even post on their forum. I'd love to teach a class in soldering, but I can't find a way to offer it. This is the email I just sent to Michael at MakerPlace:

So, my goal here is to setup and provide a class on electronics, in conjunction with the 3D printing class that John Ecker is setting up. I'm thinking there may be people who want to learn to solder and have some practice with a cheaper board before they try to solder the Gen7 electronics board for the rep rap which is about $20.

I'd like to gauge interest in such a class before I commit to it. 

I was thinking they might solder up something easy but still useful like a relay driver, or power regulator, or pulse generator. The cost would be about $10 to $12 for materials, then whatever you want to charge for hosting the class. I'll teach the class for nothing but I'd love to get some credit with you for future use of the facility. 

But I can't post the offer if I'm not a member, and I just can't justify the membership when I have a shop up here in Escondido with most of the stuff I need. 

So... where do we go? I've got everything required to teach the class, I could do it next weekend or anytime you like. But without some way to sign people up, or find out who is interested, it's dead.

 

 

I have PCBs to practice on, and the components to populate a relay driver or regulator or pulse generator or LCD panel or whatever... and they aren't expensive. I'm ready to teach a class. I've done it before, so I know how to manage a room full of guys and how to keep them from burning themselves or destroying a PCB. 

The offer is out there. :shrug:

--

James.

[Richard Rouse]

James,

Yes I mean makerplace. Oh that's how it works. I have been meaning to
sign up but right now do not need to use their stuff. Eventually a
laser cutter though.

Everyone probably wants to teach a class over there. So you might wait
in line maybe ...

Anyway it sucks if there is not free session to meet up but then again
its an amazing place and they have invested alot in it. So I can
understand where they are coming from there.

I too contacted them soon after they had an open house .... no dice no reply.

Richard

On Thu, Mar 29, 2012 at 11:56 AM, James Newton

[Jeremie Santos]

One thing that needs to be done, and one I'm going to attempt to do this weekend is to manufacturer one of these boards myself, also to just get the printer working. i think i have most of the necessary basic components. but we'll see

[James Newton]

Cool! Let me know how that goes? Are you going to isolation mill or toner transfer and etch? I assume, since you mention a printer, that you are doing the toner thing. Lots of info at:
http://techref.massmind.org/techref/tonertransfer.htm 

--

James.

[James Newton]

Well, they DID offer John and the rest of us use of a conference room if we want to have meetings there, but we can't go into the back area unless we are members or on a tour. But John dropped off the earth, and I've not seen anything posted about a future meeting of our little group. I'm not sure it's worth while meeting every weekend, but at least once a month, I would commit to making a physical meeting somewhere. And I hope we will keep in touch online.

--

James.

[Jeremie Santos]

Mill actually. I got the schematics and the free ged thing to g code. Going to try it out with a marker and paper tonight then mill tomorrow if it works

[James Newton]

Cool! So you have a mill? Or access to one at work. If that works, will you make boards for the class or for interested people? How much would you want for doing that?

--

James.

[Jeremie Santos]

Umm let me try it out first. 

[Jeremie Santos]

After playing around with the sw a bit, i realize i don't have the proper sized milling bits.. so i have yet to even try to make this.

Bits are on order and on the way.

Once i make one i can determine cost for making Gen7 for those interested

-Jeremie