Issue link: https://iconnect007.uberflip.com/i/1471044
14 PCB007 MAGAZINE I JUNE 2022 ird, there's the challenge of finding and training people. I think the biggest problem in North America today is workforce develop- ment and getting people to understand how to troubleshoot and understand where problems come from. On my calls, I'll ask, "Why did this happen?" ey say, "Well, I just turned this button on and I turned that button on." at's not good and it's not the answer that I'm look- ing for. I'm looking for what you're doing here and why you're doing it. Who's training you? at's the problem. Feinberg: Two of the main areas of plating for making circuit boards are finger plating vs. through-hole plating. ey're different. What do you see for someone who may be doing a really good job with finger plating and now they're going to through-hole plating? What do they need to think about? Carano: As far as finger plating, get good tape. Tape tightly and go from there. at's the number one thing. If you can't plate fingers, you should find a job in a pizza shop because it doesn't get much simpler than that. You put the plating in a cell with a lot of agitation, and there's plenty of tape platers out there that deliver on current density and solution move- ment; it's conveyorized. All you have to do is tape and plate it. It's pretty simple. When you put holes in the board, I don't care how many, but as the diameters get smaller, boards get thicker, layer counts get higher, the degree of difficulty becomes signif- icant. You need to understand it's not linear, it's exponential. I'll give you an example. Let's take two boards, two designs. One of them is 0.125" thick with a 20-mil diameter hole, and the other board is 0.125" thick with a 10-mil hole. Now, you might say, "I'm only cutting my diameter in half so it should be easier." No, if you really look at the models that I've built and other models, you'll see that going from a 6:1 aspect ratio board to a 12:1 with the same board thickness, that the degree of difficulty becomes exponentially more difficult. You need to readjust your parameters, your solution flow, and your anode-to-cathode spac- ing, making sure all the maintenance items are there with good cabling and proper rectifica- tion. You may have to go to pulse plating to get that current modulation that you need to get the throwing power into that thicker board. So it's not linear, it is exponential. All you need to do is look at Ohm's Law, mea- sure resistance, take a probe, take your ohmic meter, and just read the resistance between the boards. Two different ratios or two different thicknesses and you will see something signifi- cant, I guarantee you. Happy Holden: One of the things I constantly experimented with was trying to use insulated mesh to create a grid between the anode and the cathode so that I could control the cations in terms of more universal distribution, much like on a triode vacuum tube. Will anybody ever be successful at controlling those cations? Carano: Happy, you're talking about shield- ing. I've worked with adjustable shields my whole life, and that's very similar to shielding. You make the ions work a little bit harder so that you don't get overplating on the top or the bottom of the panels. But again, you can work with adjustable shields but there's enough I think the biggest problem in North America today is workforce development and getting people to understand how to troubleshoot and understand where problems come from.