Forums

Soldering a LED Display Matrix

Started by Daniel Pitts June 1, 2012
So, I've learned the hard way that it isn't trivial to solder a LED 
matrix.  I've actually extended that lesson to realize any non-planar 
graph adds difficulty to soldering.

Anyway. I was trying to build a 5x5 LED matrix (because I only have 25 
LEDs right now, and it seemed like a good start).

I got two rows in, before I realized I wasn't going to be able to finish 
it the way I was thinking.  I was soldering all of the anodes together 
for each row, and that was working fine, but then when I wanted to 
connect the cathodes, I realized I hadn't left enough perforations to 
solder enough jumpers and the LEDs. I also began to realize how much 
work it was going to be to solder it all together. I'm fine with the 
work, its good practice.  What I'm wondering though, is am I doing it 
wrong? Is there a better way to build your own display matrix? I know I 
could buy them prebuilt, and I might do that for larger projects, but 
this is a learning experience as much as a means-to-an-end.

On that same note, would it be generally cheaper to buy 8x8 led matrix 
pre-made, or to build them myself? What about if I wanted RGB display?

Thanks for the feedback.
On Fri, 01 Jun 2012 13:24:38 -0700, Daniel Pitts wrote:

> So, I've learned the hard way that it isn't trivial to solder a LED > matrix. I've actually extended that lesson to realize any non-planar > graph adds difficulty to soldering. > > Anyway. I was trying to build a 5x5 LED matrix (because I only have 25 > LEDs right now, and it seemed like a good start). > > I got two rows in, before I realized I wasn't going to be able to finish > it the way I was thinking. I was soldering all of the anodes together > for each row, and that was working fine, but then when I wanted to > connect the cathodes, I realized I hadn't left enough perforations to > solder enough jumpers and the LEDs. I also began to realize how much > work it was going to be to solder it all together. I'm fine with the > work, its good practice. What I'm wondering though, is am I doing it > wrong? Is there a better way to build your own display matrix? I know I > could buy them prebuilt, and I might do that for larger projects, but > this is a learning experience as much as a means-to-an-end. > > On that same note, would it be generally cheaper to buy 8x8 led matrix > pre-made, or to build them myself? What about if I wanted RGB display? > > Thanks for the feedback.
http://www.cadsoftusa.com/download-eagle/?language=en and http://batchpcb.com/index.php/Products -- Tim Wescott Control system and signal processing consulting www.wescottdesign.com
On Sat, 02 Jun 2012 11:49:58 -0500, Tim Wescott
<tim@seemywebsite.please> wrote:

>On Fri, 01 Jun 2012 13:24:38 -0700, Daniel Pitts wrote: > >> So, I've learned the hard way that it isn't trivial to solder a LED >> matrix. I've actually extended that lesson to realize any non-planar >> graph adds difficulty to soldering. >> >> Anyway. I was trying to build a 5x5 LED matrix (because I only have 25 >> LEDs right now, and it seemed like a good start). >> >> I got two rows in, before I realized I wasn't going to be able to finish >> it the way I was thinking. I was soldering all of the anodes together >> for each row, and that was working fine, but then when I wanted to >> connect the cathodes, I realized I hadn't left enough perforations to >> solder enough jumpers and the LEDs. I also began to realize how much >> work it was going to be to solder it all together. I'm fine with the >> work, its good practice. What I'm wondering though, is am I doing it >> wrong? Is there a better way to build your own display matrix? I know I >> could buy them prebuilt, and I might do that for larger projects, but >> this is a learning experience as much as a means-to-an-end. >> >> On that same note, would it be generally cheaper to buy 8x8 led matrix >> pre-made, or to build them myself? What about if I wanted RGB display? >> >> Thanks for the feedback. > >http://www.cadsoftusa.com/download-eagle/?language=en > >and > >http://batchpcb.com/index.php/Products
Also http://www.kicad-pcb.org/display/KICAD/KiCad+EDA+Software+Suite and http://www.seeedstudio.com/depot/ Seeed Studio offers a very inexpensive board service. Double-sided, silkscreened, with solder mask for a as little as $1/board for 5cm x 5cm. The largest they do under this service is 20cm x 20cm (not quite 8" x 8", a pretty large board) for $12 each. Hard to beat. -- Rich Webb Norfolk, VA
On 6/2/12 11:07 AM, Rich Webb wrote:
> On Sat, 02 Jun 2012 11:49:58 -0500, Tim Wescott > <tim@seemywebsite.please> wrote: > >> On Fri, 01 Jun 2012 13:24:38 -0700, Daniel Pitts wrote: >> >>> So, I've learned the hard way that it isn't trivial to solder a LED >>> matrix. I've actually extended that lesson to realize any non-planar >>> graph adds difficulty to soldering. >>> >>> Anyway. I was trying to build a 5x5 LED matrix (because I only have 25 >>> LEDs right now, and it seemed like a good start). >>> >>> I got two rows in, before I realized I wasn't going to be able to finish >>> it the way I was thinking. I was soldering all of the anodes together >>> for each row, and that was working fine, but then when I wanted to >>> connect the cathodes, I realized I hadn't left enough perforations to >>> solder enough jumpers and the LEDs. I also began to realize how much >>> work it was going to be to solder it all together. I'm fine with the >>> work, its good practice. What I'm wondering though, is am I doing it >>> wrong? Is there a better way to build your own display matrix? I know I >>> could buy them prebuilt, and I might do that for larger projects, but >>> this is a learning experience as much as a means-to-an-end. >>> >>> On that same note, would it be generally cheaper to buy 8x8 led matrix >>> pre-made, or to build them myself? What about if I wanted RGB display? >>> >>> Thanks for the feedback. >> >> http://www.cadsoftusa.com/download-eagle/?language=en >> >> and >> >> http://batchpcb.com/index.php/Products > > Also > > http://www.kicad-pcb.org/display/KICAD/KiCad+EDA+Software+Suite > > and > > http://www.seeedstudio.com/depot/ > > Seeed Studio offers a very inexpensive board service. Double-sided, > silkscreened, with solder mask for a as little as $1/board for 5cm x > 5cm. The largest they do under this service is 20cm x 20cm (not quite 8" > x 8", a pretty large board) for $12 each. Hard to beat. >
Thanks both of you for the feedback. Both of the fabricating services here are for large-scale. I'm just playing around here, not trying to sell anything. At least, not yet, and probably not for a while.
On 2012-06-01, Daniel Pitts <newsgroup.nospam@virtualinfinity.net> wrote:

> this is a learning experience as much as a means-to-an-end.
Instructables has pretty good page with instructions using a jig to solder and assemble the led matrix: http://www.instructables.com/id/Led-Cube-8x8x8/step21/Build-the-cube-solder-a-layer/ nb -- vi --the heart of evil! Support labeling GMOs <http://www.labelgmos.org/>
On Sun, 03 Jun 2012 13:57:49 -0700, Daniel Pitts
<newsgroup.nospam@virtualinfinity.net> wrote:

>Thanks both of you for the feedback. Both of the fabricating services >here are for large-scale. I'm just playing around here, not trying to >sell anything. At least, not yet, and probably not for a while.
Well, an order of 10 isn't really large scale and it costs about the same to get ten as to get one. The benefit of a real PCB is that you can make the layout -- and make changes to it -- while it's "virtual." Then when you stuff it with parts, you have high confidence that you'll get the right connections. That said, there's nothing wrong with doing a perf board or stripboard project. Poke 'em in and wire 'em up! Since your LEDs will probably have all anodes or all cathodes in common, you may find that stripboard is a good fit. You can get the bare boards at <http://www.futurlec.com/ProtoBoards.shtml> (among others) and there is a stripboard layout app (free) over at <http://veecad.com/>. -- Rich Webb Norfolk, VA
On 6/3/12 2:45 PM, Rich Webb wrote:
> On Sun, 03 Jun 2012 13:57:49 -0700, Daniel Pitts > <newsgroup.nospam@virtualinfinity.net> wrote: > >> Thanks both of you for the feedback. Both of the fabricating services >> here are for large-scale. I'm just playing around here, not trying to >> sell anything. At least, not yet, and probably not for a while. > > Well, an order of 10 isn't really large scale and it costs about the > same to get ten as to get one. The benefit of a real PCB is that you can > make the layout -- and make changes to it -- while it's "virtual." Then > when you stuff it with parts, you have high confidence that you'll get > the right connections.
I didn't see a way of ordering less than 100 on any of the sites listed, but perhaps I wasn't looking in the right place. The cost was over $1000 for a batch up 100, which is about 300 times my budget :-)
> > That said, there's nothing wrong with doing a perf board or stripboard > project. Poke 'em in and wire 'em up!
That's probably more likely what I should do. Never heard of a stripboard though, I'll look into that.
> > Since your LEDs will probably have all anodes or all cathodes in common, > you may find that stripboard is a good fit. You can get the bare boards > at<http://www.futurlec.com/ProtoBoards.shtml> (among others) and there > is a stripboard layout app (free) over at<http://veecad.com/>.
The problem I'm finding with LEDs is that I actually care about component position (spacing between LEDs), so the layout has to be "just right", or the LEDS are too far apart, or not lined up as expected.
On 2012-06-04, Daniel Pitts <newsgroup.nospam@virtualinfinity.net> wrote:
> On 6/3/12 2:45 PM, Rich Webb wrote: >> On Sun, 03 Jun 2012 13:57:49 -0700, Daniel Pitts >> <newsgroup.nospam@virtualinfinity.net> wrote: >> >>> Thanks both of you for the feedback. Both of the fabricating services >>> here are for large-scale. I'm just playing around here, not trying to >>> sell anything. At least, not yet, and probably not for a while. >> >> Well, an order of 10 isn't really large scale and it costs about the >> same to get ten as to get one. The benefit of a real PCB is that you can >> make the layout -- and make changes to it -- while it's "virtual." Then >> when you stuff it with parts, you have high confidence that you'll get >> the right connections. > I didn't see a way of ordering less than 100 on any of the sites listed, > but perhaps I wasn't looking in the right place. The cost was over $1000 > for a batch up 100, which is about 300 times my budget :-)
http://www.seeedstudio.com/depot/ click "services" on the left and then select "fuzion" in the middle I guess $9 is still 3 times your budget. there may be a way to design the board with dual purposes http://www.seeedstudio.com/depot/
>> That said, there's nothing wrong with doing a perf board or stripboard >> project. Poke 'em in and wire 'em up! > That's probably more likely what I should do. Never heard of a > stripboard though, I'll look into that.
strip board has copper tracks running one direction. the tracks are usually cut into shorter lengths to suit your applicaton. compared to bare copper the tin plated stuff is real easy to use, It costs a little more though. http://www.newark.com/multicomp/n254-899/pcb-tracks-strip-board/dp/38K6118
> The problem I'm finding with LEDs is that I actually care about > component position (spacing between LEDs), so the layout has to be "just > right", or the LEDS are too far apart, or not lined up as expected.
you only get one option with stripboard and perfboard, holes spaced 2.54mm apart, you can fit 5mm leds with 7.62mm spacing (every 3 holes) or if you grind the flanges off with 5.58mm spacing. -- &#9858;&#9859; 100% natural --- Posted via news://freenews.netfront.net/ - Complaints to news@netfront.net ---
On Jun 3, 8:40=A0pm, Daniel Pitts <newsgroup.nos...@virtualinfinity.net>
wrote:
> On 6/3/12 2:45 PM, Rich Webb wrote:> On Sun, 03 Jun 2012 13:57:49 -0700, =
Daniel Pitts
> > <newsgroup.nos...@virtualinfinity.net> =A0wrote: > > >> Thanks both of you for the feedback. Both of the fabricating services > >> here are for large-scale. I'm just playing around here, not trying to > >> sell anything. At least, not yet, and probably not for a while. > > > Well, an order of 10 isn't really large scale and it costs about the > > same to get ten as to get one. The benefit of a real PCB is that you ca=
n
> > make the layout -- and make changes to it -- while it's "virtual." Then > > when you stuff it with parts, you have high confidence that you'll get > > the right connections. > > I didn't see a way of ordering less than 100 on any of the sites listed, > but perhaps I wasn't looking in the right place. The cost was over $1000 > for a batch up 100, which is about 300 times my budget :-) > > > That said, there's nothing wrong with doing a perf board or stripboard > > project. Poke 'em in and wire 'em up! > > That's probably more likely what I should do. Never heard of a > stripboard though, I'll look into that. > > > > > Since your LEDs will probably have all anodes or all cathodes in common=
,
> > you may find that stripboard is a good fit. You can get the bare boards > > at<http://www.futurlec.com/ProtoBoards.shtml> =A0(among others) and the=
re
> > is a stripboard layout app (free) over at<http://veecad.com/>. > > The problem I'm finding with LEDs is that I actually care about > component position (spacing between LEDs), so the layout has to be "just > right", or the LEDS are too far apart, or not lined up as expected.
Advanced circuits has some 'standard' boards for $33 each. You use to have a minimum order of three... (so ~$100) but I notice that is now four pieces. http://www.4pcb.com/33-each-pcbs.html I'm not sure how that compares to the Seeedstudio that Jason posted. George H.