Looking to elevate certain high-performance components used within its Carmel AM systems, XJet found a more efficient and economical way to design and manufacture. XJet CBO, Dror Danai, explains how a ‘Eureka!’ moment led XJet to start 3D printing its own parts and jigs.

Our R&D team is constantly looking at ways to improve the performance and operation of XJet AM systems, so we continually redesign parts to move the system closer and closer to the perfection we’re aiming for, after all, the company motto is that it’s all about the details!

One of the parts we reviewed recently was our roller assembly. It’s an essential device, crucial to printing level surfaces and ensuring straight edges. If the surface alignment of each layer is not accurate, it can impact each additional layer deposited – affecting the overall accuracy of the part. With 24 printing heads and 512 nozzles on each printing head, the roller performs an essential task flattening each layer.

Most of our engineers and designers have a lot of experience in developing AM systems. This time we were looking to solve the challenge in a new way, rather than doing what we did before, so we broke down the problem – which is when one of our mechanical engineers had an epiphany.

The challenge was, because of the position of the roller assembly near some electronics, the parts needed high surface electrical resistivity, and in addition, both parts needed high flexural strength to function as intended. Whilst I describe this as a challenge, when you lay out the problem like that, we quickly saw the brief is a perfect fit for our own zirconia ceramic material – which has very high flexural strength, abrasion resistance and is electrically resistant.

It sounds obvious – we build systems for ceramic part production – so of course we should be producing ceramic parts ourselves. However, AM systems have previously been a combination of metal and plastic parts to get all the properties needed for each function – we hadn’t had parts like this made from ceramic before. Accurate, easy to manufacture technical ceramics hadn’t been available, so designers and engineers have to get their heads around a new way of thinking. It’s the same as when designers had to shift from traditional manufacturing methods and all the concerns that came with it, to all the opportunities and freedom afforded by additive manufacturing. We now have that for ceramic.

So now the roller registration pin door and roller pin lifter are XJet ceramic parts. As it says in the name – the roller pin lifter is used to lift and lower the indicator calibration pin. The calibration pin door provides safe storage for the pin when not in use. Together they enable easier, better and more accurate roller calibration. The result is absolute level surfaces and straight edges, and even more accurate parts.

Whilst our initial focus had been on precision engineering and improving the quality of parts, by going through the process we discovered that we’d also found a quicker and more cost-effective way of producing these parts. Because we needed a relatively low quantity, and plastic or Teflon parts would require a costly mold, we reaped the advantages of additive manufacturing; slashing the cost of a set of two lifter pins by 61% vs. CNC manufacturing and the cost of a pin door by 52% with XJet NanoParticle Jetting.

In addition to producing these parts for the Carmel AM system, we also produced a part for the roller bearing assembly jig in ceramic. The complex geometry of the part was going to make it an extraordinarily complicated job for CNC manufacturing, but also as a jig, we just need a one-off until the part wears out and molds are costly for one-off parts. Additive manufacturing was the obvious choice for the part, and once again, we had the right material.

The part needed to demonstrate high electrical and thermal insulation, because the device is heated to 70-80° C to make assembly easier and material needed to be hard enough to cope with the recurring action. This time, XJet alumina material was the perfect fit.

As a business, XJet’s passion has always been about making the impossible possible – creating new things that simply haven’t been achievable before. However, this time, we’ve demonstrated a simple cost-saving exercise, whilst also producing new and better parts.

We have challenged ourselves to “walks the talk” and make parts using our own technology and systems. Do you face any challenges with mechanical parts? Have you ever considered using AM with technical ceramics to resolve such challenges?
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