A DIY pcb production method suitable for 8-mil spacing?

[DirtyLude]

I have now ordered 1206 resistors.

Don't go 1206, they're huge.

I've gone to 0603 for all my caps, since I can put them closer to the IC. I'd move from 0805 to 0603 for my resistors as well, if I didn't have so many of them. It's easier if they are all the same, so I don't have to mess with part selection when making up a board.

 

[3v0]

I have to give Boncuk credit fot the layout for this PCB. He does a nice job and is much better at making parts.

The header pins on this PCB are in the same order as on the chip to reduce the via count. We have a similar PCB with the ports on contiguous pins but it required vias under the TQFP. I am still searching for a good way to make flat vias for under SMD chips.

I will order some of the longer header pins.

3v0

 

[nike6]

Don't go 1206, they're huge.

I've gone to 0603 for all my caps, since I can put them closer to the IC. I'd move from 0805 to 0603 for my resistors as well, if I didn't have so many of them. It's easier if they are all the same, so I don't have to mess with part selection when making up a board.

well u maybe know I've done away with resistor banks for LED matrix/ LED 7-segment etc.

I've got 500 pcs for a dollar or two, in most cases i use 4.7k.

also I have some 1000s packs of 1/8W carbon film,
and certain values 100s 1/8W metal film.

it's not a big issue, most of my parts are ICs.

what takes a lot of extra space is to have 4 holes in the PCB, at appreciate distance to everything, and having appreciate diameter.

changing to 1206 SMDs maybe saves 8% or 10%, compared to smaller sizes, you can also route tracks between them.

 

[srikanthsamaga]

I use Staples Photo paper. They've changed it to Gloss paper or something; I think it's in a purple envelop now. I'm not certain. I have a stack of the old stuff.

I think if you are starting out, the Pulsar paper is a good deal. If you want to move to cheaper alternatives later you can.

Double siding and other details are all in older posts.

You can always change the pad sizes in the Eagle footprint libraries if it doesn't match your requirements for etching. I had to adjust a few of them for a boardhouse with 8mil trace/spacing limits.

Really, I don't have many chips that aren't QFP, QFN, or TSSOP, all with 0.5mm spacing. If I couldn't etch for them, I'd be screwed.

EDIT: Generally I can do smaller spacing than I can do traces, so for 0.5mm leads, I do 10mil traces and let the spacing suffer. I also find with 8mil traces, the copper can seperate from the board much easier, so you can get pads that break loose if you are a little hard on them.

I have been doing PCbs with ordinary a4 sheets and got best results, But the method is too lengthy and annoying, So I asked if anybody has tried transparencies...?