Brett Tollgaard from Sunrez discusses their new leading edge protection solution, created using a durable UV-cure resin system. Using this solution reduces downtime due to quick cure times and strengthens leading edges for years to come.

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Bret Tollgaard: Bret, welcome back to the program. Thanks for having me. Appreciate it.

Allen Hall: A lot has happened at Sunrez and you guys are the magic UV cure resin systems that everybody is using at the moment, but there’s a bunch of new products that are coming out that I think a lot of operators and ISPs need to be aware of.

One of ’em. Is a fill of material that looks great when you’re trying to fix the leading edges, which are just mangled from all the dirt and debris and rain. It’s not something you can just kind of smooth over very easily. And a lot of times operators spend a bunch of times sanding, grinding, trying to get it where they can apply some sort of liquidy coating to it, and it never really looks great and it’s not really smooth.

Bret Tollgaard: Sunrez has fixed that. We sure have. We’ve got a lot of customer feedback about some of the things that they’d like us to expand our UV cure portfolio on, and one of the big ones was leading edge protection. There’s been a ton of different solutions and stuff used over the years. Some with success, some.

Slightly less mild [00:01:00] success. Uh, and so we thought it was an opportunity kind of right for the picking. And so, uh, the chemist spent a reasonable amount of time trying to develop a highly filled, uh, UV curable resin system that will live up to all the abrasion, whether it’s rain, uh, you know, particulates in the air, et cetera.

And so we’ve undergone some really reasonable rain erosion testing thus far, and it’s shown to be a pretty good result. And so it’s been a slightly soft rollout as we really kind of finalize the formula in the system. But we really do think it’s a product that the, uh, customers are gonna love, whether it’s a pre impregnated, uh, fiberglass version, or potentially a, a putty version as well.

Joel Saxum: I mean, the LEP market is, you’re always hearing about new LEP, right? There’s this LEP test, there’s a whole conference devoted to leading edge erosion that. The DTU puts on, but it’s because it’s such a prevalent issue, right? Like. Alan and I in the field looking at reviewing blade damages for lightning and things.

But we see all, all kinds of leading edge erosion. That is, it’s crazy how annuity these turbines, some of these turbines are a [00:02:00] year, two, three years old, they’re still in warranty and the leading edges look like they’ve been hit with a sandblaster. It’s crazy. So the fact that you guys are working on something and what we really like, of course, about the UV cured products is that you get up there, you put it on, boom, you hit it with the uv.

You come off the tower, you turn it back on. ’cause a lot of operators, and this is, this is where sun really shines. A lot of operators are always talking about downtime. Downtime. When we talk about installing strike tape, how long do I need to leave the turbine off before? Well, we’ve working on some solutions.

We don’t have to, uh, but. It’s a, it’s a very common thing and I really, what I really enjoy about what you said was customer feedback. So that means that you guys are in the market, you’re trusted in the market, and people feel, feel good enough to come back to you and say, Hey, what about this? What about this?

What about that?

Bret Tollgaard: Yeah. It’s kind of similar to our pre pprs. We originally offered those in 300 millimeter by 750 liter flat sheets. Uh, millimeter, excuse me. It got [00:03:00] everyone kind of on the game experiencing some of it. And then with some more customer feedback, we said, Hey, how can we improve the product, the packaging, et cetera.

And they said, 10 meter long rolls of this exact same product would be fantastic. We have less overlaps. We can cut to size, get to shape a little easier, uh, and so we’re always constantly trying to get more customer feedback so we can adapt and tailor our products to the markets that we’re in. And with that LEP is just a tremendous opportunity to really.

Try to, uh, fast track some of the opportunities to get blades back, uh, spinning quicker

Allen Hall: because there’s really two ways of attacking the leading edge erosion problem. And I think United States is a little bit different than what would happen typically in Europe, uh, especially up north where it’s mostly rain impact.

What happens in onshore for the United States is I think a lot of dirt impact dust. Mm-hmm. Dust, dust, dirt, right. Bugs

Joel Saxum: till tillable soil. Whenever we see turbines near or downwind of tillable soil, the leading edge erosion always seems to be bad.

Allen Hall: So you’re kind of getting hit with a [00:04:00] sandblaster. Yeah.

Yeah. And that’s what it’s like. Tip speeds are 200 miles an hour, 90 meters a second. You’re hitting all this debris in the air and it just beats the heck out of these blades. That’s why the OEMs are having problems in those areas. Kansas, Iowa, all those areas are a problem. So the soft materials aren’t necessarily the best for that environment.

Mm-hmm. Great For offshore. A lot of places

Joel Saxum: Absorbing rain. Droplets

Allen Hall: rain, yes. And the testing shows that, but in the Midwest, in the United States and some of the areas, India, another place really harsh, where soft is probably the not the right solution. Something a little more durable, harder wear resistant.

Is the right solution and that’s what Sunwest

Bret Tollgaard: has developed, correct? Yeah. At the end of the day, everybody wants a rubber rock. Something that can take and withstand, maybe deflect some of the energy coming at it at the same time too. Being sturdy and strong enough. Uh, to have all the wear and abrasion resistance.

And so once again, we’ve been formulating UV cure resins for [00:05:00] decades. Yeah. And so we’ve had filled products, unfilled products, et cetera, and you manipulate some of the different concentrations of different additives in there and you can really kind of tailor and tweak the performance. And so. Uh, with that we have the ability to, once again, kind of pre impregnate some fiber in case people want to just wrap and do something kind of similar to the other film type applications.

Uh, but then once again, we also are able to provide that in a putty form and so we can change and adapt the viscosity to meet a certain customer’s needs. And really kind of then based on more potential OEM and ISP feedback. As to the processes that they’d both, uh, like us to explore the most, we can certainly go down that path, uh, a little quicker

Joel Saxum: with a putty.

So I’m thinking, in my mind, I’m picturing a really nasty leading edge ocean problem on a blade. Is there a thickness limit to a UV cured product?

Bret Tollgaard: There is. And the more filler you add, the more difficult it is to penetrate through all of that. Yeah. And the, the pre impregnated repair patches, we, uh, have right now, the 73 55 resin formula, we can truly do an inch or a half inch thick, excuse me, of prereq.

[00:06:00] So fiberglass and resin, right? Um, so 12 millimeters in under 10 minutes. So a

Joel Saxum: pretty, there’s nothing that you’re gonna run into that’s gonna be worse than that. Oh, and, and that’s

Bret Tollgaard: just it. So the more fillers you add, it can change the color, it can change the wavelengths, uh, that actually penetrate through that, uh, resin.

So we do a lot of testing, um, to really dial in a photo initiated package to maximize that with the, uh, materials that we have inside the resin. And so this new, uh, system that we’re working on is our 73 0 3 resin formula. Uh, and it’s proving to be a pretty resilient system. Uh, we’ve done quarter inch thick trials thus far.

As we thought that would kind of gonna be the maximum that people were gonna be looking at. But we do have the capacity to do more if required

Allen Hall: because the, the magic, and this is hard for engineers to think about when you want something that’s really stable on the leading edge of a blade, what you’re trying to avoid is a sort of a layering system.

If you look at a lot of [00:07:00] epoxies that are apply that are. Structural epoxies, what they are is sort of a cross-linking process, and that cross-linking process also makes it sort of breakable. Mm-hmm. So if you hit it just right, it wants to fracture like a glass almost. It’s not that way, but it’s similar, right?

So the magic that sun rests has done is said, okay. I’m gonna take a system that’s cross-linked together, but also a little amorphous to take those impacts without fracturing and wearing away, because it’s the chipping and that’s what you see on leading edges for a lot of the epoxy. Yeah. It doesn’t look like it’s a, doesn’t look like it’s been a braided.

Yeah, it is, but it’s fracturing. So you’re getting these like mini explosions that are happening in a sense, and it just wears away. And then you’re exposing fiber. And fiber doesn’t like that. Mm-hmm. And then it just starts to wear burl into where Joel’s pointed out, you can put your fist in some of these blades.

Yeah. That are only a year or two old is crazy. Yeah. And I [00:08:00] think that’s where the industry sort of missed one of those areas. You could design a material. That could be quick to apply. Could UV curve could be relatively simple. You’re not mixing anything and fix these blades relatively quickly. There hasn’t been that solution.

Everything’s been a two part mix. It. Maybe even heat it up before you apply it. It’s soft. It takes hours. Secure all that. Stuff, the complex chemistry. You need to be a chemistry professor to apply some of these things to, why don’t I just put this coating on? It’s super tough, super durable. It’s going to get me past my Repower 10 year.

And I leave it alone.

Joel Saxum: Yep.

Allen Hall: I think that’s the difference. I

Joel Saxum: think another important thing we’re, we’re, so we’re in Nashville here, right? A-C-P-O-M-S. So you have a lot of ISPs that are here, and we’ve got ISP friends from all over the world. Uh, but we are, we’re hanging out with a bunch of Canadians today and they have an issue with, Hey, we can only put LEP on, or we can only do certain repairs from the [00:09:00] end of May.

To mid-September, you know, and that’s it. Yeah. So their repair season is so short that they have to change their business models around how to get people in because of it now being that UV cured, that season all of a sudden blows, blows the doors wide open. As long as your fingers aren’t freezing, you can be up there doing it.

Yeah. It’s

Allen Hall: not blowing snow.

Joel Saxum: Yeah, exactly.

Allen Hall: Actively raining hard. You could actually apply this material and protect your blades and stop messing around. Yeah, the messing around part is what kills me. Because you’ll hear operatives say, we tried that leading as protection, now we’re moving to this one, and now next year we’re gonna try another one.

Like, good lord, we’ve been on this problem for I feel like forever, and somebody

Bret Tollgaard: needs to solve it and leave it alone. Well, we try to live by the KISS principle for a majority of our things, right? That’s why our pre pprs, they’re peel and stick. You can pre consolidate it down tower if you want to build, you know, much larger versions.

Um, you can over laminate stuff over the top, but the fact that it’s peel and stick, expose it to the sun and or our light when you’re [00:10:00] ready. Is really the kind of most simple solution that you’re truly going to get.

Joel Saxum: I think. Uh, an interesting thing that I’d like to get across to the users here as well is Sunrez as a company, you guys have been working in the defense sector, like you’ve done all kinds of things For how long has the company been around for?

Bret Tollgaard: We’ve been around since 1986, so we have almost 40 years of just pure UV curing experience.

Joel Saxum: Yeah, and that’s, and that’s. It’s rare to find someone that specialized with that much experience. Mm-hmm. So you guys, while, while UV products may be new to refresh to the wind industry, they’re not new or fresh to Suns, suns knows what they’re doing.

Bret Tollgaard: That is correct. And we’d really like to tailor and adapt our products to every individual market. And so wind is vastly growing, uh, with our, in the materials and the products and the SKUs that we’re starting to offer into this market. Yeah. Um, but as we said, based on customer feedback, really kind of tailoring and tweaking systems and the LEP system, there is just no true winner.

And so we’ve been working on something over the winter that we think was gonna be a great op, uh, product to roll out. So now we’re working with [00:11:00] some other partners to really try to get this out into the right people’s hands to do testing and verification and prove, uh, you know, the concept is really there.

Yeah,

Allen Hall: it’s definitely

Bret Tollgaard: there. I’m not worried about it,

Allen Hall: that now the, the, the next effort really is the robotic application of suns materials in general. Unless you’ve kept your ear to the ground, you haven’t realized that there’s a lot of suns materials being applied via a rows robots today. A lot more than I thought.

You want to talk about how far advanced that that progress is? We, we’ve been

Bret Tollgaard: working with them for a couple of years and it’s gets back to the same kind of principle, right? If you’ve got a material that you can put on the. Consolidate and cure, that just simplifies every single thing. So with robots in particular, whether it’s a pre impregnated patch, a squeezable tube of putty, liquid resin, it’s much easier for a robot to go apply and then cure.

Yeah, and so similar with any kind of person, the reduced cycle time saves everybody money. Move on to the next repair. Get in and out before you increment weather [00:12:00] comes through or the winds start to pick up. And the robotic side of things has such an opportunity to grow, uh, and is generally just becoming a more and more safe practice as well.

Joel Saxum: Yeah. Application wise, you have OEM approval with some of your products too?

Bret Tollgaard: We do, and we are in the process of many more.

Joel Saxum: Yeah.

Bret Tollgaard: Um, we’re once again starting to gain a lot of traction in this market, and end of 2024, beginning of 2025, has been some opportunities from the exponential growth within the wind industry as more OEMs jump on board for a variety of different types of products that will solve a bunch of different needs.

And so LEP, once again, being one of them. Um, but there are some really great opportunities that are starting to come our way with more OEM support

Allen Hall: and OEMs have approved Sun Rose materials with the robot application today.

Bret Tollgaard: They are being installed in a broad variety of places and we have sold a lot of prereg into that market.

Allen Hall: And, and that’s an economic equation that’s being besides the [00:13:00] engineering right? Obviously the engineering is right to, to show structure. You can do these things. Yes. But the math works on the economy side that it’s more efficient to use a robot more consistent, to use a robot to apply a UV cured material than to put a couple of technicians on a rope to try to do this several hundred times.

Yes, the repeatability is the issue because you can’t have the same technicians doing all these blades. But you can’t have the same robot do it universally. I think that’s the

Bret Tollgaard: game changer. I think so as well. And the documentation process, the quality control they have the ability to see everything in all of their computers to really guarantee that every single repair has done the appropriate way.

Allen Hall: And isn’t that as an OAM you want? Because you’re trying to de-risk it. The reason you’re out there in the first place is because you have a problem. The worst thing is that you get out there to repair the problem and you create a secondary problem. And you can’t go back and fix it or you don’t know what caused it.

Theones has eliminated that for the most part, from what I can tell, because the data sets [00:14:00] are there. They know what the temperature was, they know what the humidity was, they know where they were they were doing, they know what time of day it happened. They have all that data to show that they’re inside the box where this is gonna be successful.

That’s a game changer. Yeah. For the industry.

Joel Saxum: And when you’re also Rupa. Okay, so we always talk about there’s a shortage of technicians and skilled technicians and trying to scale that part of it. You’re removing the need for a technician to basically be a chemist. Yes. How many times have we seen two part materials mixed with like someone’s finger or something like, like that stuff happens, right?

It does. We talked about it off offline a little bit. There are

Bret Tollgaard: some cowboys out there. Yeah, so, but

Joel Saxum: doing the, using the UV pre Prague or using a UV material, like it makes things simple. You can work with it, peel off the cover, boom, hit it with the light, you’re done. There’s no, there’s no messing around.

There’s no, ah, you know the humidity’s 76% today and the temperature’s 81 degrees in a and a half. Ah, man, we can’t do this. It also reduces downtime, makes repairs more efficient because there’s not as much weather time you. Uh, I mean, you, you, as you’ve said, [00:15:00] traction in 20 24, 20 to five. Right now, UV cured products are taking the industry kind of by storm.

Bret Tollgaard: Yeah. Yeah. And I’ve gotta say, aone has been absolutely fantastic to work with. They have some extremely intelligent people on that team, great engineer, and they really know how to make a successful product. Yeah. Uh, and so incorporating the fact, the fact they want to incorporate our UV products to really help exemplify that.

Uh, it has been a blessing for us and we’re really looking forward to see where the rest of, uh, that technology can kind of take, um, some different curing and, you know, repair opportunities. The same thing as this for Sun.

Allen Hall: One of the issues early on when we started working with you was how much of this can you produce?

Where’s it produced at? How fast can you get it on site? Having visited your facility a couple of times now, you can make a lot of material.

Bret Tollgaard: We can truly, very quickly. Yeah. We, we have, we, we buy resin, you know, buy the truckload. So we have 40,000 pounds to 120,000 pounds of resin on site at all times. We can make literally tons of [00:16:00] prereg a day.

And so there’s a tremendous opportunity for growth and volume even beyond where we’re at. Um, but yeah, we do have the capacity to bring in a tremendous amount more material. Free preg resin, putty wise and, and more.

Allen Hall: The thing about sun also is that stuff doesn’t have to be put in a freezer. The traceability doesn’t have to be there.

It’s gonna come to you in a sealed package. So is versatile.

Bret Tollgaard: You’re not throwing it out at the end of every season. Exactly. We, we guarantee 12 month shelf life on all of our products, but the reality is we’ve got stuff that’s 15, 20, even almost 30 years old that still cures, uh, just fine. And so as long as you keep it in your UV protected container.

You can really kind of, uh, recertify anything for several years beyond its, uh, original expiration date.

Allen Hall: If you think about how much material is thrown away Oh, waste because of it expired. It’s insane. Yeah. It waste, it truly is. It’s a huge waste. And,

Joel Saxum: and materials in the wind industry are expensive. They are like all the, all the glues, resins and systems like that stuff is not cheap and it’s, and [00:17:00] there is a lot of waste.

Bret Tollgaard: Yeah. And, and one of the big pushes that we had, you know, once again at the end of last year was the introduction of our new non flammable resins. No VOCs, no have. So it makes shipping, transportation, storage so much easier, literally worldwide, as all these other countries have different regulations. Um, and so yeah, moving to our new, you know, resin formulas that are.

All non flammable has also really been a big game changer for us. That

Allen Hall: allows you to ship ’em overnight on an airplane easy instead of being on a truck or on a ship. That’s huge. Correct? Right.

Bret Tollgaard: Most of the repairs that we’ve been receiving and and calls to action have been for emergency repairs. Yes. They need stuff the very next day, so we’ll get.

Stuff turned around ASAP on an airplane to their final destination. Do that with another Preprint provider. They’re gonna tell you it’s gonna be two or three weeks, not gonna happen.

Allen Hall: No, it’s

Bret Tollgaard: not gonna happen. Or I mean specialty, you know, refrigerated components to actually get things to certain areas.

Sure. All of our stuff kept in normal warehouse ambient conditions. And the reality is guys will leave these in the back of their trailer. Right. It needs to be a r uh, rugged. [00:18:00] Industrial prereg that can live up to the actual application processes and storage conditions that the reality of, uh, you know, our onsite teams actually have access to.

Allen Hall: Now, let’s talk about something that we haven’t really discussed too far, but I saw it up close, was you have the mechanical testing facilities at Sun rests to verify. The product does what you say it’s going to do mechanically, which a lot of operators and ISPs are like, oh, it’s a pre-reg, but you’re doing all the mechanical checks in house, correct?

You’re, it is back to Joel’s point, you guys have been around a long time, so it gets you the time to build all that infrastructure to do pre pprs properly. So when you’re, they’re shipping material, you’ve already validated that this stuff works and you checked it out mechanically. I know when you’re. In, in the lab and you’re playing with new materials.

I just hear all the activity like, oh, we’re, we’re pole testing this. We’re doing all the mechanical allowables, so we’re not guessing at [00:19:00] it. That’s different. Yeah. And particularly in the United States because this is manufactured in the US in America, which

Bret Tollgaard: all of a sudden is a big problem. Yeah, yeah.

Well, it benefits us, you know, being such an, uh, an old established company is we’ve been in the r and d space. For true decades. So we have a hundred kilo Newton Instron, uh, on site that we do a lot of the mechanical testing with. We have a DSC as well where we can actually measure the degree of cure of an as cured component.

So we can do an exact layout the way that someone’s gonna do it in the field with the same amount of light intensity for the same duration. We can measure the cross thickness of it to make sure that the, uh, you know, material on the backside is gonna be the same as the front. And same thing with, you know, prepregs and everything else.

So we can do mechanical testing, adhesion testing, pull test, et cetera, and also make sure that it is 99% cured. There’s not gonna be any uncross link components left in it, and that we’re achieving the right mechanical and thermal stability properties of the, uh, the material,

Allen Hall: right? So all you [00:20:00] blade engineers out there that are not familiar with UV cure materials, Sunrez has the data.

Stop. I hear this a lot. Like, oh, do they have the data? I want to see all the structural data. Do own individual test. Right. Come on, we,

Bret Tollgaard: we do have TDSs of all of our pre pprs. Yes. All the putty and everything as well. No, we are not an accredited certified lab. We’ve been doing this for decades. Uh, but I can tell you all the OEMs that have been revalidating our materials, there’s a reason we’re still selling it into the industry.

I like that word,

Joel Saxum: revalidating. Yeah, it’s

Bret Tollgaard: what it is. It, it is, and I, I respect, you know, everyone’s, you know, kind of cautiousness of really investigating a new material. A lot of people just don’t really believe until they see it firsthand, the, you know, the ability to cure the way we do. Like we’re over at Booth 1 29 here at the show and seeing people’s faces of a prereg flash some light on it, and in 60 seconds you have a completely cured part.

It’s pretty incredible to actually witness, because that

Allen Hall: was the knock [00:21:00] five years ago on UV Cure materials from other companies. Is that it didn’t cure outright or the chemical properties weren’t right, or the structural properties weren’t what they said it was. They were on the data sheet. Yes. True. I know those companies.

I know who you’re talking about. That’s not sun rests.

Bret Tollgaard: Correct. And we’re not the only UV cure player in the world. Right. But we are only one of the few, uh, that offer a UV cure pre preg. But then we also have completely different formulas to some of the things that are also out there on the market. And so one of the big benefits of our pre preg is you have a perfectly wet out sheet of fiberglass when you’re out in the field and you’re wetting out by hand.

Even if you do a vacuum consolidation and you’re pulling and you’re heating. It takes time to properly wet out all that fiber if you’re doing any kind of hand lamination and then you’re trying to UV cure or do something else afterwards. You just don’t get the same quality of a truly manufactured pre impregnated part, in my personal opinion.

Of course. Yeah. But that is one [00:22:00] of the big distinguishing, you know, functions of Sunrez as the materials that we offer and how they perform differently to the other things that are on the market. Yeah.

Joel Saxum: I heard from someone the other day that they’ve applied 3,600 of your UV patches and not one of ’em has failed.

Bret Tollgaard: We definitely pride ourselves, like every single part that we make, every single piece that we impregnate, we have a complete track record of we. I know I can tell you exact amount of resin that went into it. I can tell you the fiber that went into it. I can give you all of those data sheets to really.

Compile, uh, you know, a really, really good track record of a material traceability, but then b, success in the field because if anyone actually had issues, which once again should never happen. ’cause of all the checks and balances we have, the reactivity checks and stuff that we do. But if by, you know, some really, really important misfortune, someone had a product that didn’t act right, I know exactly what batch record it came from.

I know all of the other prerequisites that were manufactured with the same material, the same resin on the same day, [00:23:00] so we can go back to all the other customers in case there ever was an issue. And so we’ve yet to have one, we’ve yet to ever ship out material that didn’t cure and didn’t do as, uh, as advertised.

And we’ve sold millions upon millions of pounds of resin, uh, and thousands of miles of pre preg. But, uh, yeah, we do have all those checks and balances in place as well.

Allen Hall: So for the engineer or the OEM or the ISP. Operators that have not heard of Sunrez and want to find out more,

Bret Tollgaard: where did they go? So we are truly starting to finally build up a website, uh, that has all of the information that people want.

So we’re putting SOPs on there, we’re linking, uh, videos on our YouTube page and everything to it as well. Because at the end of the day, now that we are starting to get as much exposure as we are, people are coming to us with the same questions. How does this work? What are the best processes? Gimme some hints, tips and tricks.

And so we’re developing all that content. Now, we’re rolling out more every single month, so by the time this airs, we’ll hopefully have even a couple more videos out. Um, but yeah, [00:24:00] sun rez.com, youtube.com/sun Rez, uh, are the best places to go to find some of the quick content. And of course, just reach out.

We’re available by phone, email, um, you can get to us on our website and everything as well. Yeah. And that’s

Allen Hall: Sunrez, S-U-N-R-E z.com. That’s correct. Brett, thank you so much for being on the podcast. Appreciate the time and thanks

Bret Tollgaard: for having me back, guys.

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