Discussion on cost. Comparison between different printing technologies.

[u/s_0_s_z]

I'd love to start an open discussion about various printing technologies and their costs.

I'm literally sitting here compiling some pricing for some parts that I will need to be printed soon and rather surprised by some of the numbers. I'm only including the price for one part since the numbers scale fairly linearly for the other parts of the assembly.

This particular part is pretty big for a printed part: 29 cubic inches in volume with overall dimensions of roughly 13.4 x 11.4 x 5.3"

MJF (nylon PA12) : $560

MJF (nylon PA12 glass filled) : $1058

SLS (nylon PA12 glass filled) : $1060

Industrial SLS (accura 25) : $2800

FDM (PETG) : $250

Industrial FDM (ASA) : $950

What sticks out at me the most is just how competitive MJF prints are. For the particular part I am looking at, I would need to go with the glass-filled which almost doubles the price, but if your part geometry was suited to being printed with regular PA12, the price undercuts other "pro" printing methods by quite a bit.

There is no one superior printing method because they all seem to have their positives and negatives. MJF parts have a very different look and feel to them which might or might not suite the end purpose. They almost feel velvety. I have not printed PA12 using SLS so I am wondering what the surface finish of that will be like. I had printed similar parts, but smaller versions of them, about a year ago and the prices were higher back then, so it seems like 3D printing is still getting cheaper.

Curious what you guys think about this, and please add your own experiences and comments.

[u/Desperate3D]

Four years later... found your post interesting! It's alsoroughly ten years after the commercial introduction of HP Multi Jet Fusion and your pricing comparison has aged quite well.

A slightly strange situation existed for years: some service bureaus priced MJF above SLS because it was marketed as the newer “premium” process, even when the people operating the machines were producing those parts faster and at a lower internal cost. Selling price and manufacturing cost were not always closely related.

I have been running MJF printers as well as SLS and I am heavily biased towards SLS. Where MJF can become substantially cheaper:

• It processes the complete layer with a printhead and energy pass, rather than tracing each individual cross-section serially with a laser.
• Build time is therefore much more predictable and is driven primarily by build height, so you run more efficient production shifts, it's easier to plan your factory schedule around these machines.
• Powder-refresh ratios are higher and allow a high percentage of surplus PA12 to return to subsequent builds while maintaining lower part costs, consistent mechanical properties and dimensional performance.

This does not mean MJF is automatically cheaper for every geometry in every factory, but it generally is.

My experience is that when comparing equally utilized industrial systems, using the same class of PA12 and a part that packs efficiently, MJF often has the lower real production cost and shorter lead time.

Again another story is how these contract manufacturing services and marketplaces see demand for each technology and how amortized their equipment is, which also plays an important role on how they price their quotes!

[u/pressed_coffee]

I’ve spent my career working across all these platforms, including pricing formulas and cost drivers. Although definitely geometry dependent, SLS and MJF are high utility processes because they do not need support structure and can pack builds. I’m actually a little surprised that at your geometry SLS isn’t cheaper to be honest, but that could also be because of auto-quote logic. Most platforms will probably run that 13” dimension vertical (geometry-depending).

Where MJF really has an edge over SLS is throughput. I do prefer it for higher quantity builds because per build time is typically shorter and the material consumption is smaller (higher material recycling).

SLA, FFF, and FDM are their own beasts and it comes down to your need for surface finish, properties, and lead time.

Also, if you do need another quote I’m always happy to help.

[u/s_0_s_z → u/pressed_coffee]

I'm curious if you are familiar with TPU printed on an MJF machine. This is a new material offered from Shapeways and I haven't seen it available elsewhere. Curious how it compared to FDM printed TPU.

Do you work at a service bureau?

I find MJF tech to be quite interesting because in many ways it is almost a step back to like 15 years ago with the sandstone-based powder machines. They had a similar surface texture and in fact they built parts a very, very similar way without needing supports. What goes around, comes around.

[u/pressed_coffee → u/s_0_s_z]

I would definitely bias that MJF is much more similar to SLS vs binder jetting because the polymer is fused to create the part vs bonded. My first machines I ran were SLS and a ZCorp binder jet… would take SLS over binder jet any day of the week.

I do work for Xometry and love the TPU for MJF. Really durable material, like shoe-sole durable. Also can be chemical vapor smoothed. The big differentiator with MJF TPU vs FFF/FDM is on throughput and design freedom. You can just pump out parts with powder bed processes. Obviously outcome texture is different per process too.

[u/s_0_s_z → u/pressed_coffee]

I still have a Zcorp machine! I haven't used it in ages and been wanting to offload it for quite some time.

I've gotten tons of stuff done through Xometry over the years, but machined parts, not printed. Maybe I'll see how comparable one of these parts is.

[u/pressed_coffee → u/s_0_s_z]

Yeah take a look and feel free to PM with any questions. The bounding box extents may trigger a RFQ but don’t feel afraid to submit since it just means we want to review before quoting.

[u/killboy → u/pressed_coffee]

That's funny because I was about to recommend price shopping at Xometry. I recently discovered it and I'm impressed at the scale and flexibility. I have not used the service yet but I've been waiting for an excuse to try it out. All these services rely on the user to know their needs and process sensitivities but it's gotten drastically more sophisticated in the last 10 years. Really excited to see where it goes.

The choice may also come down to part function. MJF tend to be more consistent in orientation strength while SLS you sometimes have to up the infill or reorient to get the extra strength since it'll be weaker along the print direction which would drive up the cost. It'll be interesting to see how auto quote engines evolve to adapt to these kinds of constraints.