The big Plasma Cutting debate, Water Tables vs Downdraft Tables. Which works best for your application. Chris Phillip from AKS Cutting Systems breaks down the pros and cons of each. He also talks about how plasma tables work, as well as how AKS became one of the first Cutting table manufactures in the USA.
Narrator: Welcome to the Dusty Jobs Podcast from Imperial Systems. Industry knowledge to make your job easier and safer.
Donovan: Good afternoon, and welcome to Imperial Systems Podcast. We’re here again. We’re glad to have Chris Phillip with us from AKS. How are you doing today Chris?
Chris: Good. Good. I’m doing well. We drove in this morning from just north of here and had a nice little factory tour. It’s just a good day. It’s finally somewhat spring-y out. That’s an advantage.
Donovan: Yeah, nice weather day today. We’ve been working with you guys on different products for how many years now, with AKS?
Chris: Probably since really your inception into dust collection and plasma, I believe. So four or five years now, at least.
Donovan: We’ve had a good long relationship, you could say. For everybody out there listening who doesn’t know who you are, or who AKS, how about you give us a little bit of background on yourself. Let’s start out with you. Tell us about yourself first and then tell us about AKS.
Chris: Sure. So, I’m Chris Phillip. I’m one of the regional sales managers AKS Cutting Systems and my territory is eastern PA, so starting at State College and going east, Maryland up to Maine and New York State. In that territory I manage somewhere around, on a good day seven to eight dealers, on a bad day three or four dealers, depending on who’s doing their job that day. That’s what I do. I drive around. I live in Cleveland, Ohio, right about twelve minutes from our factory. I drive around and fly around and go meet new people who want to get into the world of plasma cutting or want to get into the world of laser cutting and really need a plasma table or people who want to get a waterjet as well. That’s also a world I dabble in as well.
AKS has been around now for, boy, 120 years. My great-grandfather purchased the business in the late forties I think is the most accurate story I’ve heard so far, and my grandfather, Dale Phillip, ran the business for fifty years. Maybe a little longer than that, somewhere around there. My dad, three or four years ago, took over the presidency. My grandfather is still CEO of the company, and I got out of that office as fast as possible and got on the road. I wouldn’t trade it for the world. I love being on the road.
Donovan: You could say plasmas in your blood almost.
Donovan: Not technically. Not actually.
Chris: Actually, technically, it can.
Donovan: Oh, that’s true!
Chris: Theres plasma in your blood. You need it there. That’s actually a really great little story. When my grandfather first got into the plasma industry, a guy called him out of Luxembourg or something. Somewhere – Switzerland or something. He said, “Hey, have you ever worked with plasma before?” We made automotive assembly lines. We made gauges to measure distribution caps for airbag deployment, any kind of gauges for nuclear rod insertion systems, making high speed battery assembly lines…we were all over the place. Imploding torpedos with liquid helium, all sorts of random stuff. We were the essence of a job shop. The guy called him and said, “Hey have you ever done anything with plasma?” This is like in the early 80s.
So my grandfather says, “No, we don’t do anything in the medical business.” He didn’t even know that plasma was a thing that you could cut with. Obviously now everybody knows that plasma is one of the three main technologies that you use to cut steel, and stainless steel, and aluminum plate. When we started in this twenty-five, well, boy, thirty-five years ago now, we had no idea what we were doing.
Donovan: Thirty-five years ago you guys were probably one of the first ones in the states to be using this technology.
Chris: Definitely. We were actually exporting them to Europe because for some reason the European market place started using CNC cutting technology. It seems at least to me a little bit quicker than the United States steel processing centers. Now it’s everywhere. Now we have over 1,500 installations and we make 100 or 120 machines a year.
Donovan: Now, when you say 120 – because you guys carry a variety of different types of machines, correct?
Donovan: So you’re talking total machines, or are we talking about just plasma tables? What are we talking about?
Chris: Yeah, total machines. For every five plasma tables we sell, we sell about one waterjet, which is in line with the market distribution as well. When you look at how many waterjets are sold nationally and how many plasma tables are sold nationally that’s about the ratio as well.
Donovan: So, kind of like your grandfather, when I see a plasma table working I am like, “How does this thing even do what it’s doing?” It’s interesting to watch it cut, and you’re like, “What is going on here?” Now, can you tell us, for people that are a little bit ignorant like me what is the actual technology? What is it doing there?
Chris: No, I can’t, because even after doing this and living in it I’m still pretty amazed by it every day that I see it. I can give you a rough metaphor of what it’s doing. You’re taking a tremendous amount of energy. Usually it’s 480V 3 phase, 67 amps. So, a lot of power, maybe 70 kW of power into this system. So, you think your lasers in the world – if you get a 10 kW laser, wow. That’s big time. That’s big time. You’re cutting half inch plate. We’re taking seven times that and we’re putting it into an area about this big, maybe an eighth of an inch big.
How it gets there is kind of interesting though. So you get this three wave form electricity, AC electricity coming into your shop. It’s going like this through the air, and there’s this device called a chopper. It’s actually a really old piece of technology, but because of the power levels that you’re dealing with you’ve got to use them. It’s the only thing that’s robust enough to deal with this. What the chopper does is kind of like what the power supply on your laptop does. It takes that AC power and turns it into DC. So it actually chops up those waveforms – that’s why it’s called a chopper – and it makes it into a nice positive line. Hopefully. That’s the idea, unless you’ve got dirty power. That’s a separate conversation. We then take that and somehow it gets from the power supply, the big black box that Hypertherm makes. That box is 80% chopper. That’s the big thing that you’re buying in there, and then a lot of oscilloscopes and other pieces of technology to make sure that line is as straight as it can be.
Donovan: So 80% percent chopper, 20% magic?
Chris: Yup. Yeah. Somewhere…20, 25, maybe it’s over 100%. I’m not sure but its a lot. Then that goes into the torch body, and I’m definitely cutting out a lot of parts here but there’s high frequency stuff that’s going on. It gets to the torch body. It gets to the nozzle, to the electrode, and that electrode. That’s basically, I believe it’s the cathode in this relationship. It’s going to start arcing back and forth, and then you run a gas through it, and the gas turns into plasma. So plasmas the fourth state of matter, right? So that gas…you know, you’ve got solid, liquid, gas, plasma. When you super excite a gas with electricity, 60,000 watts of electricity in area this big, that’s a way to get that going. You do that and then run a gas through it at a high pressure and that gas actually becomes magnetic as it turns into a plasma. That wants to then grab something, right? It’s magnetic. So it grabs the steel plate that’s right below it. When it hits that steel plate, that 70,000 watts of power is also the temperature of the surface of the sun.
Chris: So, it doesn’t just melt it. It actually ionizes the material. It changes state again and turns it basically into electricity, at least a small portion of that material. Most of it gets melted, and then you have 150 psi assist gas that comes out that then actually blows the material out of the way. That’s basically the gist of how plasma works. We’re taking super high voltage electricity, arcing it, running a gas through it, and letting it do it’s thing.
Donovan: In a controlled pattern.
Chris: In as controlled as we can get, yeah. That’s the part that people always want to know. They say, “What’s the accuracy of your plasma table?” They’ve got three machining centers. “What’s the accuracy of your plasma table? Can it hold five tenths? Can it hold ten tenths?” The answer is imagine trying to hold a candle, and you want to know where that flame is. It’s really, really hard. Theres ways to do it. You can measure it, but it’s tricky. Obviously just like a candle one of the byproducts of having that flame is a lot of dust.
Donovan: Well, yeah.
Chris: Which takes us to the reason why we’re here on the Imperial podcast.
Donovan: That’s where we step in and start helping out with that. Now, from my base knowledge on plasma tables and boy I have a lot more know from just that conversation.
Chris: It’s all wrong. It’s all wrong. Any service technicians that are listening right now just close your ears to that last five minutes. It’s going to hurt.
Donovan: As that chemical process is happening that’s allowing that to cut that metal there’s obviously some byproducts and that’s what we’re talking about. There’s smoke, and from what I understand there’s two ways that basically the industry uses to capture that. That’s a bed of water underneath it or actual sucking that smoke down through the table. Is that…am I getting anything wrong here?
Chris: That’s the two methods that I know of. The third method is you just don’t care enough and you let it fill up your shop.
Donovan: I’m sure you’ve been in some shop…
Chris: It gets interesting. You don’t want to be in those for too long.
Donovan: I know we had one time out here where for some reason when someone changed the filters in our own collector they forgot to engage them so they were actually up tight and we had some blow through on our plasma smoke and very quickly we knew in our shop as everything started to turn orange that we had done something wrong.
Chris: You guys cut a lot of mild steel so that definitely makes sense. It’s interesting. You can actually tell what product you’re cutting or what material you’re cutting based on the color of the smoke. Your aluminums its going to be a whiter smoke and on your mild steels, your carbon-based steels it’s orange. What is burning metal? We all know what burning metal really is. It’s oxidation. It is extremely accelerated oxidation. So what you’ve got there, the byproduct of cutting this material, along with the slag that falls off and the part that’s made, that stuff that isn’t there had to go somewhere. I know there’s a lot of magic in the box. But there’s not much magic on the table. That’s pretty simple. The answer to that is that it oxidizes and it becomes that smoke. The reason it looks all orange is because or rust. It’s rust. It’s rust flakes that are flying everywhere through the air. They’re just a lot smaller than what you consider rust.
Donovan: Well, that makes a lot of sense. So, when we’re talking about the water based tables and we’re talking about the air based tables, can you kind of tell us a little bit…I mean I’m sure each one has some advantages, some disadvantages. Can you tell us a little bit more and unpack if someone’s listening to this and trying to decide if they should get a water based table or “Should I get an air based table?” What would be some things that they should think about?
Chris: Well, I’ll prep that question by saying that I am, and this is no accolade to Imperial, I’m 100% downdraft.
Chris: 100% downdraft, and the reason being is because of that idea that we started with this conversation. Controlling the candle. We’ve figured out that you can just have a candle waving in the air. You can have a plasma torch that’s just doing it’s thing like we did back in the early 80s when we didn’t really know what we were doing. Since then there has been all sorts of developments. There is the different PSI assist gas. You can take that candle flame and if you run a high speed current of air up the side of that candle, guess what? You stabilize that candle flame, right? It’s called a shield gas. Same thing that we do. We run a cut gas that gets electrified and turned into the plasma arc. Then there is also a gas on the outside of that, just like a welder does, that isolates that gas, the plasma arc, from ambient air. We don’t really know what’s in the ambient. Theres a lot of nitrogen. Theres other stuff. Who knows? By doing that, by isolating that flame from atmosphere, you really include the quality of your cut.
Donovan: Right, it gives it more of a controlled environment to live in. You’re saying on a downdraft table then that helps assist with that, right?
Chris: We’re getting there. We’re getting closer. So after they did those types of shield gas type things, they were still cutting, plus or minus, twenty, twenty five thousandths of an inch. Maybe more than that. Fifty thousandths of an inch. You think it’s minuscule but a human hair is about five thousandths of an inch. So we’re cutting hairs here, literally. That’s what they were living at when they started doing that. They started looking at other variables. What else can we change? At that point, basically everybody was using a water table. They just said, “It captures it and it works.” Somebody eventually had the idea of, “Well, we know that by cutting this we are obviously causing a lot of thermal changes in the material, and maybe if that was more consistent we would cut better.” Meaning, “Why are we quenching the bottom of the plate with water?” This is a thermal process. We’re melting stuff. What if we just let air be underneath the plate? That improved the quality of cutting. You don’t get as much dross. When you cut the material, obviously some of it is liquid and it’s going to build on the bottom of the plate. If you cool it right away, more of it’s going to build on the bottom of the plate. Makes sense, right?
Chris: Also, it causes more thermal things to occur with the material. So, in my experience across the board, if I want to show somebody a really good part…you know, the system we have in our facility, when we cut samples for customers all day long, it’s a downdraft system, 110%. It would never be a water table.
Donovan: I got you, because you just get a little more of an accurate cut. You get a better cut.
Chris: I’ve had this conversation, obviously, literally a couple hundred times with people trying to decide between a water table and a downdraft table. I should say this. There are two huge factors in determining where a customer is actually going to end up between plasma and water jet. The first one is their space. Huge. In the plasma world the dust collector is honestly kind of seen as a pain, you know? I’ve got this big thing that I’ve got to deal with. It takes filters. I’ve got to do stuff to it. For some reason a lot of these guys look at the water table and they say, “Oh, I just fill it up with a hose and you’re good to go.” Then they’re surprised when somebody knocks on their door and says, “Hey, have you bought your 5,000 gallons of plasma table additive to add to your water every month to keep it from becoming a cesspool in the middle of your shop? “Whoa, what’s this?” So that’s definitely a big thing, that people think that it’s easier to have a water table.
Donovan: I think a lot of people don’t – once the water is in there, it’s hard to know what to do to get rid of it, too. I know we’ve had some calls like that in our own facility. We don’t deal with that so we’re not really experts.
Chris: What do you say to that?
Donovan: We say that they have to contact someone else that’s a hazardous waste manufacturer or disposal. “We’re not able to help you with that. Sorry.” If you want to get a downdraft table we know what to do with those filters when they’re done. That’s another question we usually get, what to do with this water. The best answer I’ve come up with, I don’t know if you know a better one, is to contact your local hazardous waste disposal people.
Chris: Yeah, you can actually contact a sewer cleaning company.
Donovan: Oh, okay.
Chris: They’ll bring in a pump truck and they’ll take an eight inch hose set up on some diaphragm pump, and they’ll take that eight inch hose and suck out your whole table dry in about forty five seconds, as long as they can access the table. They have to be able to back a truck up through your shop, and that’s usually the catching point because if somebody buys a water table, one of the bigger reasons why they want to do that is space. Two big factors: space, and the other one I actually haven’t gotten to yet, but it’s what they’ve already owned in the past. Usually if they’re buying it, it’s because they have piles of steel everywhere. Theres two rolling machines in the way. Theres a brake and there’s no way they can get a truck to the table. So they say, “That’s great. What else?” The answer to that is buy yourself a little sump pump, put it in there, get a 55 gallon bucket, and start pumping that thing out and dumping it down the drain until you have a wet sludge of empty table and then you have to go in there. Maybe if you have a guy who might be on his way out the door or something you can tell him to go clean out the water table because I wouldn’t want to do it. You’re just left with the gunk that builds up in the table that’s sat there for maybe a year with the water stagnant and all the drop outs and stuff. It gets gross. You can do it. People do it all the time. A lot of people still do it. The reason a lot of people do it is that second reason. It’s what they know. A lot of people if they had a water table they’re just going to get another water table. They don’t see the up front cost of a dust collector as advantageous because they’re blind to the dross they’re dealing with, the extra rust that they’re dealing with, all the extra stuff that the downdraft system helps alleviate the cost of down the line.
Donovan: Yeah, if you don’t know, you don’t know. So, do you feel like we’ve covered everything with the downdraft table setup? You know more than I do. If theres anything else out there that might be good for someone to know.
Chris: Yeah, I mean, I guess the only other thing that people definitely worry about with downdraft systems is the possibilities of explosions. That’s obviously a big thing, especially when you’re cutting aluminum. Powdered aluminum is literally what’s used to make military grade explosives. So, one of the byproducts of cutting aluminum on a table is powdered aluminum, basically. It’s the dust that’s created from the cutting, that white dust. With your spark arrestor properly maintained and the systems that you guys have offered, we cannot say with the couple hundred installations that we have that we have had an issue with the system being maintained and used they way it should be. The spark arrestor in particular is…I was just poking around and if you haven’t seen one on the inside look it up. They have some good cross sections on Imperial’s website. You can’t drop big drops into it. You’ve got to clean it out once in a while. That can be hard to get people to accept once in a while. If you maintain it, it shouldn’t be an issue.
Donovan: That’s why we build the clean out door on it, so you can do that, so you can inspect it. Everyone’s inspection level is different and how often you need to do it. Some of that comes down to the operation. Sometimes that comes down to the operator on that piece of equipment. You’re right. It’s good to poke your head into that every once in a while and make sure it’s good whether it’s every six months…we always, and I’m sure you guys do too, we always encourage preventative maintenance on everything. That’s with every piece of equipment you have in the shop. Anybody who’s running a shop knows that you’ve got to look at stuff every once in a while, right?
Okay, so, wet versus dry, I think we’ve got a really good feel for that, where we’re at, what the industry is like. So, I’m going to ask you a question and I know you’re not a doctor. I’m not a doctor, but one of the big questions we get people looking up is plasma smoke. What is the health implications for that, if I’m breathing that in? People get worried about that. I’m sure you’ve gotten asked that question too, being what you do for years and years and years. I’d love to hear what your answer is on that.
Chris: Cutting stainless steel in particular is a known carcinogen. That’s something that is factually know. You don’t want to breathe in the dust that’s creating from cutting stainless steel. Hexochromium variant gas, that’s the byproduct. Apparently that means its bad for you.
Donovan: *laughing* The name is just scary itself.
Chris: Aluminum, one of the byproducts of aluminum is hydrogen gas, which, something I didn’t touch on with a water table is with aluminum, you get hydrogen gas build up under the plate. That will eventually blow up. You’re worried about your dust collector blowing up once every fifteen years. If you don’t have a properly maintained bubbler system inside your water table you could have an explosion once a week on that. I actually saw one where a quarter inch plate of aluminum, they hit a pocket of hydrogen gas underneath it, and it looked like a thanker when through it. It hit the beam. The beam lifted up. It was a lot of, “Whoa, that was neat.”
Donovan: We’ll just pause here for a second on the dangers of smoke and I want to talk about one thing. If you have a wet table, are you saying that still doesn’t collect everything that the byproducts are? Are you saying you still might need a ventilation system on that? You’ve seen a lot more of these in the field. You’re talking about it could possibly blow up. Is that something that even on a wet table you might still want to consider? I’m going to let you speak to that.
Chris: Sure, definitely. In an ideal setting, if you’re using your water table properly, meaning you’re running your water about half way up the side of your plate. It has an internal bladder system so when you take your one inch plate of steel and you put it on it, it is up to the bottom of the plate. That’s really important. You can’t have a gap. You can’t have an air gap there. If you have an air gap, the smoke just goes out from underneath the plate and you might as well not have anything. So you’ve got to keep that water up. Well, by having that water up then you deal with all the issues that the guys down the line don’t want. That after the pain of a capital expense up front goes away, your production guys say, “Well every part I get off this machine has dross on it, and there’s flash rust on the bottom. Lower the water.” So they lower the water just a little bit. Now their dust collection went down from 95% or so to like 10%, but their parts turn out great. They say, “Well, I have a water table, so let’s just not worry about it. Theres a lot less dross because you’re not quenching the slag as it comes off the part. You’re running a current through steel in water. You get rust, right?
Chris: You can flash rust a part in a couple seconds, especially when it’s submerged in water. You can literally watch the rust grow on a piece of steel. It’s kind of wild.
Donovan: So you’re saying when people do that, when they drop that water level then…
Chris: Yeah, then they’re not even using the water table. They have the water table. They’re maintaining it. They’re cleaning it. They’re doing everything they need to do. They paid more for the water table on the base system than a downdraft system, at least the ones I sell. Our downdraft tables are cheaper than our water tables. But you still have smoke that gets out. So now you’re dealing with all the negatives of the capital costs of a water table and very few of the positives. That’s after six months. You got back into a shop and sure enough, you see that they’re running it below where they should.
Donovan: We’ll just throw this out there. If that happens, and you guys need some other type of collection system, Chris, you can definitely help them out with that. You can help them figure out a solution for that. Whether it’s a hood, whether it’s whatever…
Chris: I liked your ambient system out there in your factory. That’s a nice system.
Donovan: It’s working really well for us.
Chris: I could see that in a lot of shops.
Donovan: It’s a good solution. We’ve talked about that on a previous episode with Jeremiah, so if anybody is listening and they want to go back and look at industrial setups that’s one of the things. You can go back to that podcast episode and listen to that and Jeremiah can walk you through what an ambient system is. Alright, so that dangers of plasma – we’re coming back around to the health implications. So, a lot of it comes down to what you’re cutting.
Chris: Yeah, at the end of the day I don’t know if mild steel smoke is actually poisonous. You know, like you said, we’re not doctors, but I’ve watched guys have to breathe it in and it looks a lot like welding fumes and it doesn’t look nice. You can be around a plasma table and watch it cut one inch plate for five minutes and literally watch smoke billow off the table in rolling fumes. This stuff, you’ll watch it settle, and everything around you, the whole shop is covered in orange. It can’t be good for your lungs. I can’t believe it would be. You know, if you walk away from something coughing…
Donovan: That’s probably a good indicator.
Donovan: Well, Chris, I think we’ve talked a lot about how different tables work and everything. Is there anything else that you think people should know about out there or can you think of anything else we haven’t touched on that might be beneficial?
Chris: Yeah, sure. So, the last thing that I leave you with is understanding that when you’re making this decision between a water table or a downdraft system we’re in between technologies. Laser cutting or plasma cutting, all that type of stuff…get samples. Get samples from your supplier, honestly. I can get you some samples cut on a water table or cut on a downdraft system and there’s notable differences. When you hand those to an operations guy and he looks at those two parts and he says, “Well this one is going to take me five minutes of grinding to prep. This ones going to take me thirty seconds to prep.” That’s the game. That’s it. Those five minutes add up very quickly. All of a sudden you’re employing two more people just to grind the parts because the water table is set too low and you’re not even collecting the dust anyways and you’re dealing with bad parts. I think the water table back in the day made sense, but now we’ve gotten all these other variable solved to the point that we’re looking for other things. The next variable is sticking with downdraft.
Donovan: And efficiency and just trying to…if they’re trained to weld, you want them to be welding. You know what I mean? You don’t want them to be messing with parts more than they have to. You want them to do the job you’re paying them to do. I get it. Uptime, productive time, is helping people make money. That’s what you guys want to do, that’s what we want to do. We want people to be productive, and we want them to be in the healthiest and safest environment that they can. That’s what we’re trying to do on this podcast is help people understand what’s a good decision for them to be healthy. That’s what you guys are doing over at AKS, trying to create a good, healthy shop environment.
Donovan: Thanks for coming on. I really appreciate it. Everyone who is listening, you can check us out on social media. You can like, subscribe, check us out there. AKS, do you guys have a lot of social media?
Chris: Yeah, we have all that stuff too.
Donovan: So find us all on Twitter, LinkedIn, YouTube, all of that. Chris is glad to talk to you. I’m glad to talk to you if you have any questions. You can check us out there. Until next time, stay healthy, stay safe and we’ll be looking forward to talking to you again.
Chris: You go it. Thank you for having me on.
Donovan: Yup, thanks for coming.
Narrator: Thanks for listening to the Dusty Jobs Podcast. Breathe better, work safer.