PCB Etching Nightmare

what kind of pan did you use ... glass or pyrex I hope?

Tom Woodrow

Bennet Williams wrote:

No. It was Tupperware. I figured that was OK since most etching tanks use plastic. Even the $150 model uses polyethylene (plastic).

BRW

It's been years since I did this but....After exposing don't you have to remove any unexposed resist using a special solution? You mentioned rinsing but what with? Perhaps it's water but I can't remember.

Did you heat the Ferric Chloride?

It Helps a lot if its at a temperature of 100 F to 120 F or even a little more.

Take care.....Gary

Try some agitation during the etch. Orienting it either vertically or face-down in the etchant speeds things up. Laying it flat with copper-up will take forever.

You say you stirred for 30 minutes. Hmmm. Maybe you need new etchant. The bottle you bought from Radio Shack may have been from 1972.

Blake

It was unused, but it may have been old. The bottle was very dusty.

BRW

No. You don't remove the unexposed resist. The resist is what creates your circuit in the etching tank. You just rinse the board in water.

BRW

No. But I've decided to break down and buy a $40 etch tank with a heater and bubbler. I am also going to try a higher quality board (if price is any indication) - M.G. Chemicals 600 series. It costs $6.50 for a 4" x 6" board vs. the $2.50 for the board I was using. I figure if I throw enough money at this problem, it will go away. I'll probably end up spending so much that I could get 10 boards done at professional PCB house. The problem is, I don't have the PCB layout software that they need.

BRW

There is an abundance of low cost software that can output files used by most pcb houses. What house are you talking to? What software do they need?

Regards, Brad PC Logic

Schematic entry and PCB design software

After exposure, did you rinse off the un-exposed resist with the proper solvent?

Harry C.

Thanks Richard. I'll look into them. It looks like a top-notch organization. Have you used them?

BRW

Not yet. But their customer list reads like "Who's Who" of blue-chip technology companies. I will certainly use them for my next project.

One word of caution. Most of the free software from a pcb house will not produce industry standard files. You will have to go to them for additional copies and so on. Think razor blades here. The entry price is very low, but they get you on every board they make for you. Brad PC Logic

Schematic entry and PCB design software

1.Expose Riston board for approx 90 sec in light box (depends on tubes)

Etching in a heated bubble tank will usually take only minutes depending on freshness of etchant and amount of copper to be removed.

Ross Herbert

Bennet Williams wrote:

This how to do it.

but did you carry out the DP50 stage?

Geo

Geo,

If you are referring to me, yes, I did do the DP50 stage as per instructions

Ross Herbert.

Geo wrote:

It is a nice site. I'd like it better if it also included information on environmentally responsible ways to dispose of the used chemicals and maybe also sold stuff to facilitate doing so.

Allan Adler snipped-for-privacy@zurich.ai.mit.edu

• *
• Disclaimer: I am a guest and *not* a member of the MIT Artificial *
• Intelligence Lab. My actions and comments do not reflect *
• in any way on MIT. Moreover, I am nowhere near the Boston *
• metropolitan area. *
• *