FR4 PCB quality?

[Miska]

Can there be big quality differencenses between different FR4 boards?

I've used KELAN stuff that Farnell sells. Is pretty expensive (almost ?6/$7 for a single sided 100x160 w/photoresist) but I wanted good quality. Today I found a surplus source selling same size etc. for ?2. These are 1.5mm thick with 0.035mm copper layer. Don't know the brand.

So what could the difference in quality be? Badly attached copper? I'm tempted to buy a big pile of this cheaper PCB but don't want to end up having my precious projects on bad PCB.

Furthermore, how long can I stock unused photoresist laminate?

Should tube projects be made on PCB with a thicker copperlayer?

Cheers, Miska

 

[Emperor-TK]

Biggest variable here is the photoresist. It has an expiration date. Even when new, not all resists are created equal. Bad resist is simply not worth the effort. I'd try one of the cheep ones out first before commiting to buy in quantities.

 

[Miska]

Of course! Stupid me, I should have realized that after developing B&W pictures ever since I was 10... Same thing there with the papers...

I quess this is why some people don't like making their own PCB's. I mean, they probably tried first with a cheap, low quality laminate and got bad traces. I did my first boards with KELAN laminate and got very good results right away!! :grin:

Thanks for help!

Miska