After years of reviewing technology products, Linus Sebastian, the face of the popular YouTube channel Linus Tech Tips, decided to show the world how it’s done properly: the LTT screwdriver received universal praise from both hobbyists and professionals, often described as “The one you always need!” But how does one make a best-in-class screwdriver? As it turns out, 3D printing played a significant role in the process. We sat down with Kyle Tharratt, the project leader, to discuss their creative process and the three-year-long journey from the initial idea to customers. Watch the studio tour at LTT.

The LTT screwdriver has received a lot of attention for its unique design and functionality. What sets this screwdriver apart from others on the market?

The LTT screwdriver is our take on a best-in-class multi-bit ratcheting screwdriver. The body is based on Megapro’s long-standing and reliable design but has been significantly modified to suit our needs. We aimed to create an extremely durable screwdriver made from high-quality materials, featuring an ergonomic grip that fits naturally in your hand and reduces fatigue during use. That sounds self-evident, but there aren’t that many screwdrivers like that! Ours has details that help provide an unparalleled user experience, like easily accessible in-handle bit storage, a strong magnet for superior bit and screw holding, a knurled shaft for precision control, and an ultra-low back-drag ratchet. I’m extremely happy with our result, as are hundreds of thousands of customers!

What was your role in the project?

I was the project leader on the LTT screwdriver. However, I don’t want it to sound too fancy, it was a project many people here contributed to. Making the screwdriver took us three years and was also my first project at Linus Media Group.

What was the state of the project when you started?

On my first day, we had just an idea and a rough handle model. That was the work of Alex Clark. He knew what Linus wanted in general, but didn’t know exactly what features the model should have. Part of Alex’s design philosophy is to make a ton of different versions and have Linus try them all. To do that, we used our Original Prusa MK3 to make all the physical prototypes Linus got to try and play with. After his feedback, Alex went back to make more iterations until he came to the final design: a three-sided design that sits naturally in your palm and just beautifully fits. Thanks to that design, you have a more comfortable screwdriving experience.

With the handle ready, what was your next step in the process?

We had a design for the outside of the handle, as well as options for the end cap and the selector. Linus had already chosen the selector he liked, so my first goal was to choose what end cap we would go with. And that wasn’t easy. The design came from a hired company that pitched us four options. And Linus had… well… objections to each of the four versions we had. (laughs) So what I did was I 3D printed the whole screwdriver and sanded down some layers to make it look as close to the final product as possible. I used the PrusaSlicer’s feature of inserting a pause to put magnets in the handle and about 17 different end caps that I designed. Then I had Linus hold the screwdriver, and I changed the end caps until he felt one that he wanted. We eventually landed at something that was very close to the final look, only more square, kind of boxy-looking. A little bit of SolidWorks later, trying different
angles and prototypes, we were ready, and Linus wrote the check to the tooling company. And boy, was it a six-figure kind of expensive! And it came down to me to have the final word – whether we are ready.

Were you nervous about spending all that money?

What do you think? (laughs) Before making the big decision, I used the SL1 to make an as-close-to-accurate prototype – just to be sure. The resin-printed model was as dimensionally accurate as I could make it with what technology I had: it had the final selector, handle, and end cap, as well as all the internal features. I gave it to Linus, saying, “This is what we’re going to make.” And we went for it.

Why did you go for the black body and an orange cap?

A funny story is that I didn’t have the working end-cap from the injection molding company when we prepared to present the working prototype. But I had the 3D-printed one. The screwdriver was supposed to be all-black with the injection-molded part, but I popped the 3D-printed orange one on, gave it to Linus, and said, “This is prototype number one.” And he put it on Twitter about 20 minutes later. And that’s how the orange screwdriver came to be: everyone responded, “The orange one is great, I want that!” That story might be fun to tell, but it shows how accurate the 3D-printed prototypes were. I could just take one and put it on a final product, and it worked like a charm.

What is it like to design tools and products for Linus?

Linus is a discovery-type creator. He creates by experiencing and discussing how he thinks it could be improved. So the best thing is to put something physical in his hand. This is how Alex progressed with his handle – Linus had a vague image of a better screwdriver than he had used at the time. So Alex put an idea in his hand, and he responded by giving him feedback. So, other iterations were made, and that led to more ideas.

What’s the most significant advantage for a manufacturing engineer like you when using 3D printing?

3D printing was essential in creating the screwdriver, and it is used in all our engineering projects at the Creative Warehouse because it cuts the time spent talking to Linus. (laughs) As I described, it’s best to approach him with something physical, and that cuts down the whole development cycle. It takes just a couple of hours to 3D print things. So, we can make seven to eight examples of what we’re trying to create in a week. When you’re choosing between options, I find it better to create many different prototypes rather than one at a time. You can simply put aside the ones Linus hates and combine the features he liked on others. In a way, it gives us a better way to communicate with Linus – gives us a channel to the part of his mind where he has all these great ideas. It turns them into real things. If we just asked him, “What should we do?” he’d say, “Make the best screwdriver in the world!” That would be it. (laughs) With 3D printing, you get quick feedback, direction, and more ideas to work with.

Wouldn’t a CAD model presentation be more effective?

Showing Linus CAD models doesn’t always work; it’s just not the same. The same goes for a render – it might work for a t-shirt design, but not when you need to pay attention to stuff like feeling the handle in your palm or measuring weight… The weight is a great example – it can tell you a lot about a product. If you pick up a screwdriver and it’s light, nine times out of ten, people will say it’s cheap. When you pick up a screwdriver, you need to feel some heft.
When you have to deal with a guy like Linus, who has a perception of quality, he needs to be able to pick it up and feel confident about it: “If this is going to be the final part, then I’m happy.” Without a 3D printer, you’re stuck doing things that require traditional subtractive manufacturing, which comes with a lot of complexity and time. If you’re trying to give form to your thoughts and ideas, 3D printing can take you most of the way there.

Does 3D printing make sense cost-wise?

The more you can keep the prototyping cost down, the more prototypes you can make. Simple math, right? Every time you make a product, there are costs, and there has to be a business case made with it. When pitching new products to the top-level management, I have to consider the engineering time and prototyping costs. Even though you might not see that underlined on the revenue minus costs sheet, it does count. If we made a successful screwdriver but at a cost of millions and millions for prototyping, we’d never see any profit from the product. But thanks to 3D printing, we could cut those costs down while still effectively prototyping! Basically, you don’t want to spend thousands when you can spend hundreds, right? Time is money. Spending a month on a prototype that Linus picks up and hates – that’s not money well spent, right? Therefore, 3D print, iterate, fail – but fail cheap – try again.

Do you remember when you first started 3D printing?

I’ve been an advocate of 3D printing since its early days – back when you had to control the printer through a command line and had to print from the weird ABS stuff that didn’t deserve to be called filament. My first 3D printer was a MendelMax 1.5 that I built by myself, and it lasted just one print. (laughs) I completely destroyed the extruder. My interest in the technology grew later when PLA became available – and since then, I have always had multiple 3D printers at home and work. As a mechanical designer, you can’t NOT have one, in my opinion. But that’s just me. (smiles) Aside from PLA and TPU, I only use PA12 from an SLS 3D printer. Only because that is the closest thing I can make to a final product, it has properties similar to those of our injection-molded stuff. And we can predict all kinds of problems with it.

Will there come a day when you’ll be using FDM-printed items as final products?

That’s already happening – if you print something and someone buys it, it’s a final product! (smiles) For example, NERF accessories are mostly 3D-printed and sell like candy. There are plenty of print farms out there, and they do a great job! As for us, the day might come, but it’s not something we are focused on right now because it’s not our core business.

Jakub Kmošek and Štěpán Feik