making my own pcb's

[jrz126]

Ok, I'm looking into making my own PCB's and I have a bunch of questions (I'm gonna wirte them as I think of them):

1. Does the ferric chloride require extra shipping charges due to it being a chemical? I might just buy from my local radioshack, is it possible for the chemical to lose it's effect over time?
1A. If it doesn't require extra shpping should I order the crystal or liquid?
1b. How much echant is needed to develope a 6.75" X7.25 double sided 1 oz copper board? (it's about 100 sq inches total).

2. How much easier does the "press n peel" paper make it to print these boards? I read about using photo quality paper and even using pages out of magazines, is it significantly easier to use the P&P (easier enough to drop $10 for 5 sheets)?

3. Where's the best place to buy the drill bits?

4. EDIT: What size heatshink tubing should I buy? I'm going to use the tubing over every LED connection that I have to solder. For these connections, I plan on just wrapping the wire (20awg? I salvaged the wire from inside old printer cables, so whatever common size that is) around the lead and putting a glob of solder on it.

5. EDIT #2: I noticed that in my layout, some of the nets for the IC's start on the top layer. How do I solder these on the final board? Do I just put enough solder on the bottom side and hope it connects? Also, Do I have to worry about the the via holes being under some of the IC components? I would think that the solder would get in the way when I go to put the sockets in.

 

[gerty]

Harbor Freight has the drills, set of 50 for $12.95.. They're used, resharpened
and come in random sizes, but they're sized for pc board work. I bought a set a year ago and I was satisfied.. Be aware they break easily as they are tiny and made from solid carbide, a drill press of some sort is definetly recommended.. As for heat shrink you'll find that you'll use several different sizes , it's real handy.. The most common sizes that I use is 1/16 and 1/8..

 

[John Sorensen]

Do I just put enough solder on the bottom side and hope it connects?

That won't work. Trust me. I use #30 AWG wire to connect layers (vias).

I would think that the solder would get in the way when I go to put the sockets in.

That depends on the socket. Some sockets are "open frame" and you might get away with it. For a DIY once-off project, and density isn't too high, you'll probably be better off if you don't put vias under components.

j.

 

[Dean Huster]

If you have a double-layer board with no plated-thru holes, sockets become a liability ... the intermittent, expensive things are a liability anyway. Dispense with IC sockets and solder them directly to the board and you can solder a lead from both sides if necessary. If you absolutely must use a socket that needs double soldering, the old Molex Soldercons were one iffy way of handling the mess, but I don't know that those are available anymore.

Avoid RS for your stuff. They're 'way too expensive.

Kelvin Electronics has always been a good source for PCB chemicals and other supplies and they have attractive prices, also. Trouble is, I don't know if they will sell to anyone but schools, which really sucks.

Hosfelt Electronics used to sell the carbide resharps, but you could buy all of them in one size rather than having to deal with an assortment like Harbor Freight. I use a Dremel tool in a drill press stand with excellent results. Spins the bit at a few million RPM for great holes. BE DANGED SURE TO WEAR SAFETY GLASSES/GOGGLES WHEN DOING THE DRILLING OPERATION since you never know when a bit will break and send a shard toward your face.

Dean

 

[jrz126]

for the chemicals, Radioshack sells 16 oz for $4.25. I'm probably gonna buy from electronics express, they have 32 oz for $7.50 but if I have to pay a lot extra for shipping of the chemical, then I might as well buy it locally.

 

[Optikon]

Spins the bit at a few million RPM for great holes. BE DANGED SURE TO WEAR SAFETY GLASSES/GOGGLES WHEN DOING THE DRILLING OPERATION since you never know when a bit will break and send a shard toward your face.

Dean

LOL. :shock: A few million RPM and a bit shard would be dangerous indeed!

 

[kentken]

Sodium Persulfate works better then ferric chloride, and is cleaner.

I get mine from: **broken link removed**

Kent

 

[jrz126]

electonics xpress has ammonium persulfate I know it's similar, but what would you recommend?

 

[vaineo]

i don't think they charge extra for shipping it if you buy it in a powdered form, liquid they might.

 

[jrz126]

cool, I'm gonna call them to put my order, so I'll just ask then.

Ok, I'm working on routing the board, what should my track to track, and track to pad spacing be?

 

[jrz126]

ok, new question,
what should I set the size of my VIA holes to? It's defaulting them to .02 drill and .036 pad. I'm making this board myself, and I think that is way too small. I was thinking about changing it to .035 drill and .045 pad. does that sound like it would be ok?