Electronics permeate the world. They are in nearly everything we use. In Part 3 of WGLT's weeklong series about local manufacturing, we visit a Bloomington company that serves both farms and the armed forces with made-to-order circuit boards.
Static
To get onto the clean, airy, and well-lit production floor of the Zentech facility just off East Empire in Bloomington, you have to put heel straps on your shoes to eliminate electrostatic discharge.
Industrial fans keep humidity and temperature-controlled air flowing throughout the area.
They don't want to zap the electronics produced in the 95,000-square-foot section of an old IRS warehouse. The paint on the floor has an additive that prevents static from building up. And you have to wear a smock that bleeds off any charge your clothes create by rubbing together.
Production Manager Christy Shook said people hand-placing components on printed circuit boards or soldering them in also have to plug into the desks.
“You'll notice those two slots up there, one's black and one's yellow. The black one, the employees, when they're standing on there, also have to plug in. What we call this is for a wrist strap that attaches to the smock, and it goes in. When they're actually working on boards, physically at the table, you will see areas for them to plug into,” said Shook.
![Electrostatic discharge [ESD] is the enemy in any electronics production facility.](https://npr.brightspotcdn.com/dims4/default/1f2b7e3/2147483647/strip/true/crop/4858x3470+0+0/resize/840x600!/format/webp/quality/90/?url=http%3A%2F%2Fnpr-brightspot.s3.amazonaws.com%2Feb%2F84%2Fe41a3c9b44f096c30339b1dd857f%2Fzentech-esd-grounding-sign-bollinger06.jpg)
It might seem a little over the top. After all, Zentech tests everything before it leaves the plant. But Marketing Director Stephanie Austin said damage from static might not turn up right away.
“That's the hard part about it, a latent defect, meaning it's found in the field after the fact, and it fails. And our environments are all mission critical. That's super important to not have happen,” said Austin.
Zentech was founded in 1998 in Baltimore. It has another facility in Dallas. Zentech moved into its Bloomington center in 2015, gutted the place, grounded all the pillars, and put the special flooring in. They are a build-to-print firm, which means the customer has a drawing from which Zentech builds the circuit board assemblies. The boards can have everything between 10 and 2,000 parts.
Customers
A lot of what Zentech produces is for the military aerospace sector. Account Manager Todd Jaglinski is reticent about precise products, but of the top 30 defense contractors Zentech does work for 26 of them. And Austin said the technology changes over time.
“For example, you'd have a lot of on-land equipment in Afghanistan. Now we've pulled out of Afghanistan. So then it'll be different types of drone technology that we're now working on," said Austin.
Zentech also produces circuit boards for other industries — agricultural grain dryers, for instance.
“When you're driving around Central Illinois and you see the big grain silos, and they have the yellow, kind of oval on top of that. We support that customer. The boards that we produce for them; it actually goes in and runs the drying system. It sets the temperature, measures the humidity,” said Jaglinski.
Making circuit boards
The production area at Zentech in Bloomington is set up in a U-shape. Parts come into inventory, flow around the horseshoe through various processes then back out the door for shipping. Jaglinski said initial printing is with a long machine that robotically inserts parts for a given board design. A bare board goes underneath a stencil.
“There'll be solder paste on the top of the stencil. It'll squeegee the solder paste through the apertures on the stencil onto the board. So that's basically putting the solder paste, which is the glue that holds the components on after solder reflow,” said Jaglinski.
There are several long multistage machines for what’s called surface-mount technology. Shook said workers load components into the machines which are programmed to place them on the printed circuit cards.
“There are suction cups that pick and place all the components and place them down on a board. It's screen printed with solder paste. It runs through there as the machine places all the parts, and by the time it comes out to the end, they recheck the components to make sure everything is good, and then it goes through a convection oven to solder it to the board."
They can make rigid flat boards and curved boards and boards that flex. There’s automated quality control as well. Zentech recently bought a 3D Automated Optical Inspection machine.
“It's basically taking a picture of every single part on the board, and it is comparing it to a golden, known good board ... verifying it has the correct part number on it, it has the correct polarity, it's in the correct spot, it's sitting the correct way,” said Jaglinski.
It’s not all automated. Sometimes components go all the way through the board or are placed above the printed card. People do that work.
“If their solder joint is too close to something else and they can't get in there without disturbing the other parts around them, when nobody else can get to it quite like a person,” said Cindi Rutledge, surface-mount technology supervisor.
After surface-mount placement, the circuit board goes through an oven to cause the solder to flow. And It’s tricky. The oven needs careful Goldilocks-just right treatment. If it's not hot enough, the solder won't reflow. If it's too hot, the solder will burn off and the component won’t sit solidly in the board.
“What we do for each product is we do an oven profile. We have a unit that we put through that actually takes temperature readings on individual areas on an assembly. We make sure that the whole assembly is getting the correct temperature to get proper reflow in the reflow oven,” said Jaglinski.
The ovens have four different temperature zones.
Occasionally something will need more direct heat than the oven can give. Those components go to hand soldering.
Soldering
Soldering is an art. To get the tiny amounts of solder where they need to be without spoiling things takes precision and maybe some creativity. People who like little details love this job.
Logan Bardole is an up-and-coming star of soldering, according to the company. He was hand soldering for a hobby and liked it.
"I'm really into, like, retro games and arcade like, hardware and equipment. So I got a few things. They end up being broken. No clue how to fix them at all. So I ended up buying, like, a cheap, $30 Amazon iron, and just kind of learned from trial and error,” said Bardole.
Which games? Bardole says he liked fixing up Neo Geo, Street Fighter, Mortal Kombat, and even Centipede and Pac-Man boards from the 80s.
Logan got all his certifications for Zentech in his first year. That's fast for a training track. He said, though, there’s always something new and a creative new way to approach it. For instance, recently a whole circuit trace lifted off a board.
"Very, very carefully, you have to take an X-Acto and just break off whatever is lifted. We have templates basically that come from a manufacturer, and then you have to glue it down by hand. And you're talking something that's probably the size of like a grain of rice," said Bardole.
And if a board is not designed properly, hand solderers add jumper wires on the board to correct it.
Bardole is not the only hand solderer. Brian Wade actually has a title — fastest solderer in the world. Yes, there’s a competition for that.
A few years ago Wade won it, getting through the U.S. and Canada division before regional champs around the world came together to solder it out.
"The regional is a small circuit board. You have to hand place a couple dozen parts, and it has to be soldered in compliance with IPC Class 3,” said Wade.
IPC Class 3 refers to high-reliability electronics for mission-critical applications, say healthcare, outer space, or war. These are designed to function without failure over extended periods, sometimes in high heat or extreme cold.
“For the world championship, we had an hour to complete it. I was done in about 35 minutes. The second-place guy was done in around 53. I'm pretty fast,” said Wade.
Coating
Whatever comes off the production floor goes to the coating room where Corina Streutker is the supervisor.
“There are several areas on a board that do not need to be coated or are keep-out areas. We'll need to mask those off, spray around them, and then once we spray them, we will look at them under a magnifier and find out what areas, small, little areas, need to be coated, or if their coating got in the wrong area, we'll take it out,” said Streutker.
Streutker uses a machine sprayer for silicone coating. Urethane or acrylic coating happens by hand. Everyone wears hair nets to prevent contamination.
Streutker said if you like to craft or paint or do small little bits of work, coating is for you. The challenge is to make a good-looking quality board in a short time.
“A small little board, the size of a quarter is only going to take a, you know, a minute. If you've got a board the size of 12"x12", it's going to take 40-45, minutes just to touch it up, and then, and then you flip it over, and you'll do the other side,” said Streutker.
She uses a blue light to check the boards before they go out.
Workforce
Zentech workers come from a variety of places. A couple have left for Rivian and then come back.
Christy Shook used to work for a package manufacturer. Cindi Rutledge used to work at Caterpillar. Corina Streutker grew up in California on a dairy farm. Zentech was her first non-milking job. Brian Wade moved from Alton to Bloomington. He’s been doing it a long time. Logan Bardole came to Central Illinois from tiny Mifflinburg, Pennsylvania, nickname “Buggytown.” He’s still in his 20s, a rarity in this field.
Zentech Marketing Director Stephanie Austin said the country is struggling right now to find workers, even as the federal government tries to enact policies to reshore manufacturing and make the U.S. less dependent on foreign sources. Austin said all critical infrastructure depends on electronics.
“A lot of our folks in this industry are aging out, and a lot of our younger generation, though they use all of these electronics, aren't necessarily aware of the amount of complexity that goes into making them,” said Austin.
Austin said Zentech is trying to raise awareness and advocate for the industry, to try to get kids interested in electronics engineering and manufacturing. It works with Heartland Community College and other training institutions and will get workers wherever it possibly can.
Our series Made in Bloomington-Normal continues Thursday with a visit to Symbio Bioculinary, a startup in Bloomington on the cutting edge of food production.
