On 07 May 2014 16:49:49 -0700, you wrote:
>Good Morning guys (I'm in Australia), and first of all:
>
> THANK YOU VERY MUCH EVERYONE. I didn't expect such a great response. I've now got a much better insight into what's involved.
Yer welcome.....
>
>
> Regarding assembly I think I'm leaning more towards a low quantity test run of boards and FOR NOW I'll put the components on myself. If more serious interest in my little board is shown as word gets around, then I can look into getting the assembly done for me too. I feel like I'll be more of a hassle to a manufacturer at present if I go the assembly route.
>
Good idea in terms of money, I think. BGA stuff you want them to do,
leaded flatpacks, you can do.
>
> I'll have to do some research on soldering SMD components. Some say that once you get the hang of it you'll find it easier and quicker than through hole components. If that turns out to be true I'll redesign the board with SMD parts, which will also reduce the size. And having a professionally made board with solder mask should help greatly.
>
Just as easy, in the long run.
Solder mask helps greatly. You need a very good temperature
controlled iron. I use Metcal myself.
Use lots of flux when soldering flatpacks. If you solder blob
anything, do not panic. Just keep on going with the rest of the pins.
Practice will help. I use solder wick with an added flux (it helps
me). That sucks off the excess solder, and the solder that flows
under the chip (don't ask), comes out on the wick. You will get the
hang of it. A super small tip is not as needed, but one that covers
one or two pins is good enough, this on 0.5mm spacing pins, TQFP-100
or TQFP-144.
For resistors/capacitors, I generally put a small blob of solder on
the pad, (use flux, RMA is good), and then heat the pad and push the
part onto the pad using a pair of tweezers. Then at a later date,
solder the other end of the part. Again, if it makes sense, it'll
work well.
>
> Making the PCB itself is actually quite easy for me but the hole drilling is the hard bit. I ended up mounting an electric die grinder on my 2400 x 1500 CNC plasma table and drilled the holes that way, talk about shooting a fly with a bazooka. Too much hassle overall when I look at the pictures of the professionally made boards, they look beautiful.
>
Hole drilling is easy enough with a smaller (carbide) drill. I will
use #76 or so for feedthroughs.
Now plating through the holes, that's another matter. I hand drill
the holes (using a Proxxon with 1/8 collet, carbide drills, and at the
highest speed for small holes). You need a sensitive drill press as
well, no wobble at all. Then thread wire through, and solder one
side, then the other, then cut all the wires.
I'd prefer plated through holes, thank you very much.
>
> It's quite a simple board and as a hobbyist I've made everything big and chunky, much bigger than necessary. For a PCB manufacturer I think they won't come much simpler / easier, no fine tolerances here.
>
Pads are a little larger because of hand soldering, that works well.
>
Harvey
> Keith.