With plated through holes what diameter is recommended for common part lead sizes, like 1/4 watt resistors, IC socket pins, small caps and diodes? Is there a...
1081
sheebeehuh
Feb 1, 2011 3:27 pm
ExpressPCB comes with a variety of standard component footprints built-in including resistors, caps, IC's, etc., etc. Just select the "Place component" tool...
1082
snmavronis
Feb 1, 2011 3:44 pm
Thanks, I want to also know if the ExpressPCB pads for said components represent the actual drilled hole size or account for the thru-hole plating thickness...
1083
Michael Darnell
sheebeehuh
Feb 1, 2011 3:58 pm
The holes have a tolerance of +/- 0.10 mm so a 0.74 mm hole could range from 0.64 mm to 0.84 mm. The plating thickness is insignificant in light of that wide...
1084
snmavronis
Feb 1, 2011 4:25 pm
"Standard MiniBoards ($51) are 2 layer PCBs without the solder mask or silkscreen layers. 4 Layer MiniBoardPro boards ($98) are multi-layer PCBs that include...
1085
Tom Becker
b19063
Feb 1, 2011 4:41 pm
... If you aren't using the top-side copper of the miniboard, you might consider putting the silkscreen patterns in copper. Tom...
1086
snmavronis
Feb 1, 2011 4:56 pm
Yeah I've done that for text things like my name and board title and some pad numbering like for pots. I'll just expand on that....
1087
blisscomm
Feb 2, 2011 2:29 pm
... The hole sizes account for the plating. If you click Help >> Manufacturing Specifications, you will see this, for "Standard Miniboard Service". I guess...
1088
snmavronis
Feb 3, 2011 2:08 pm
Thanks. I just have to watch out for tricky stuff like hole sizes for Alpha 16mm right angle PCB mounted pots that I use and other components not defined in...
1089
Michael Darnell
sheebeehuh
Feb 3, 2011 2:31 pm
I use Alpha in one of my designs. I measured the lead thickness at it's widest chose a hole size slightly larger (accounting for the 0.10 mm tolerance) and...
1090
snmavronis
Feb 3, 2011 2:54 pm
I love custom part building in ExpressPCB, so cool. Thanks for the tip on what you do for the Alpha lead holes! Right now I've only made 2 custom PCB layouts...
1091
Blair Hogg
blairhogg
Feb 4, 2011 12:09 am
I believe that the general rule of thumb is to have the hole size 0.010" larger than the lead diameter. For square or rectangular leads use the diagonal...
1092
snmavronis
Feb 4, 2011 3:18 am
So, according to the spec sheet Alpha recommends 1.20mm holes for their PCB mount pot leads. 1.20mm = 0.047244" so in your design did you choose a 0.046" hole...
1093
blisscomm
Feb 4, 2011 1:34 pm
... I think plated through holes give a much stronger connection than single sided boards without plated through holes. Even if the holes are somewhat bigger...
1094
blisscomm
Feb 4, 2011 1:58 pm
... If the pins should be a little bit too big for the holes, you could file them down. This would slightly weaken the pins but that would probably be better...
1095
Alvaro
barcellos.al...
Feb 4, 2011 9:25 pm
Hi, I want know if is possible do PCBs like this one (old): http://library.solarbotics.net/circuits/pix/BHB_PCB_layout.gif or ...
1096
Blair Hogg
blairhogg
Feb 4, 2011 10:47 pm
Yep. Just define copper planes with holes that either attached to the plane or with a thermal relief. Right click on your hole, select top or bottom layer pad...
1097
Blair Hogg
blairhogg
Feb 5, 2011 2:13 am
Your other option is to make the entire board a filled plane and define the spaces in between as keep out areas. ... From: "Blair Hogg" <blairhogg@...>...
1098
Ronald Shaul
ronaldshaul
Feb 5, 2011 3:40 am
Yes, both of these PCBs are very doable with ExpressPCB. I have done these before.    Ron  ________________________________ From: Alvaro...
1099
johann_ohnesorg
Feb 5, 2011 3:26 pm
Hy Alvaro, the PCBs you linked to look this way because they are made with a router, the trenches are not etched but milled and drilled with a small router on...
1100
Alvaro Barcellos
barcellos.al...
Feb 8, 2011 10:40 am
Hi, Thanks, I had done by hand, using redefine planes and filled. My question is if hava some "automatic" process to do it. Rgs Alvaro ... [Non-text portions...
1101
Alvaro Barcellos
barcellos.al...
Feb 8, 2011 10:48 am
If don't have a automatic process, maybe will be a good project search it. for basic eletronics, low frequencies, large plane copper areas and etc. Rgs Alvaro ...
1102
Alex Babchanik
sanko98837
Feb 8, 2011 12:50 pm
I'm looking for the same chip part layout (48-TSOP). If anyone has it, I'll appreciate it....
1103
Michael V
michael_vale...
Feb 8, 2011 3:15 pm
What's the physical difference between a via and pad of the same dimensions? I've gotten used to using vias to connect traces on different layers, but I don't...
1104
Steve Maroney
computergsteve
Feb 8, 2011 5:50 pm
For one, a pad always goes through all layers. VIAs are meant to be used to connect to layer 1 to layer 2, but not to layer 3 or layer 4, or any similar...
1105
Blair Hogg
blairhogg
Feb 8, 2011 6:16 pm
Generally a via is smaller, has less copper around it in an annular ring, and in some cases may have solder mask over it. Since vias are not usually soldered,...
1106
Michael Valencia
michael_vale...
Feb 8, 2011 6:49 pm
In the Expresspcb program, both pads and vias require the .017" around it. I also looked at the resulting solder mask layer, and both have solder mask. So it...
1107
Michael Valencia
michael_vale...
Feb 8, 2011 7:06 pm
I can take a pad and via, and connect them to the top, bottom, and one and only one of the inner layers, so i still don't see the difference between them in...
1108
expresspcb@yahoogroup...
Feb 8, 2011 7:28 pm
Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the expresspcb group. File : /SMT - TSOP...
1115
augieesposito
Feb 18, 2011 8:02 pm
I am creating a schematic that, like all schematics, is made up of out board wiring, and the circuit board. It has the typical board connections between the...
