Prototype Build

3D Print bed material choices

By | Prototype Build | 3 Comments

Robox® has a removable print bed, it simply clips in on top of the heater element. This allows us to provide a range of bed surfaces for different fused filament fabrication (FFF) or machining purposes when a different head is fitted to Robox. We are testing several materials to select one to be the standard bed for shipping with Robox, additional beds will be available that provide different performance on certain prints.

A lot of Robox users will tend to make most of their prints using PLA because it gives good results very quickly and easily with lower print temperatures and less shrinkage as it cools. ABS is much better for prototypes and items that will be used for more than display or visual checks, it is very strong and can be machined following printing, eg sanded or drilled without melting.

Our tests have shown that there are a few bed materials that have all the right properties to make an excellent all round print bed, we are testing the best way to make these beds remain flat over a range of temperatures and remain usable after a large number of prints, importantly they must be able to transfer heat into the printed parts to control shrinkage and the part must remain stuck to the surface.

Currently Glass and ThermoSurface are standing out as good options. We could supply the first FFF versions of Robox with either of these beds and it would perform very well.

We are tending to use a ThermoSurface sheet as our print bed as most of our prints these days are in ABS. The ThermoSurface bed when used in a controlled environment allows us to print objects using ABS that would often detach from the bed or warp and cause unwanted variations in the shape and finish of the printed part if we printed using a glass bed.

The perfectly flat surface of the bed is very important for many printed parts, particularly larger parts, ThermoSurface can deform much more than glass. This can effect the bottom surface of the part and the heat transfer from the heated bed underneath.
Glass on the other hand is naturally flat and extremely stable through a huge range of temperature or chemical environments. If we were only to offer printing in PLA then the glass bed would be an excellent option.

Glass is cheaper than any of the other materials we are testing, it can be simply cut to shape while other beds will require molding or other processes to work as we intend them too.

What would users want? A cheaper option that will cover the majority of their printing needs? Or a more expensive option that will allow a bigger range of materials and model shapes but which may need replacing after a certain number of prints? The various beds we make will all be available as add on or replacement items so a user can have the best properties of all of these beds. The question is which one do we include in the first package?


The image in this post is from


A quick espresso cup design that can be spiral printed - haven't had time to test the design yet, the Robox sample is being used by Peter at the moment!

3D Printed future: Designing for Spiral Printing

By | Chris Elsworthy Design Blog, Prototype Build | 5 Comments

Over the weekend, between taking the kids to birthday parties (Happy Birthday Addy!) and clubs, I experimented with Robox and spiral printing. Having downloaded the obligatory vases and sliced them using the Slic3r experimental spiral print function, it was really quick to get some good results and I was pleased with the performance of Robox. After getting bored with vases, I CAD’ed up a Robox version and printed it, which was good but left me thinking there must be more to spiral print than vases…


Vases 100mm tall, 0.15mm layer height, 1mm wall printed using the 0.8mm nozzle.

The quality of prints were fantastic, in-fact some of the best surface finishes I’ve seen from a 3D printer, but what I was most impressed with was the speed and ease they were produced. One of the benefits of Robox is that due to it’s large nozzle (0.8mm), we can print a single outside perimeter that is 1mm thick, meaning great quality rigid prints, fast.

Why can’t everything be this easy to print?  –  We need to start designing products and parts that take advantage of this new manufacturing technique – I don’t just mean orienting them in the build chamber and slapping a flat bottom on so the part will stick to the bed, but really designing things that can be better if made with a 3D printer. One of the things we’ve been printing a lot in the office is a whole lot of espresso cups (don’t ask why, you’ll find out later) which are taking ages… but spiral printing could not only make them quicker to print but also have a better surface finish and introduce more features. Why not design the cup so each layer has a single profile, handle and all, and vary the wall thickness where needed? You could even have an inner and outer wall like a Thermos flask to keep your coffee hot and the outer surface of the cup cool.

First prints on our prototype

By | Prototype Build | 2 Comments

We have been printing with the first complete prototype, the results are very promising. In fact the hardware is working just as we imagined it, just a few tweaks to improve the speed, the accuracy is spectacular!

Every imperfection in our test prints is just down to tuning in the print parameters. Between the software and firmware we can set everything we need too thanks to Ian and Ben W’s hard work. There is still a lot more work to do to make all this control accessible to Robox users.

Our intent is to allow the user to simply press print and get a good result every time. The building blocks are in place and we now have complete control of every aspect of the print process, now its time to tune the system.


Exciting times! – Robox® Dual nozzle 3d printer prototype testing

By | Prototype Build | 2 Comments

I’m watching over Chris Elsworthy’s shoulder – actually under his armpit…he is a tall man – while eating my lunch.

There is a definite sense of excitement in the office.  We are usually heads down working hard to bring the many elements of Robox from plan to reality. Right now though, everyone is watching Chris’s desk.

Following closely behind some unrepeatable language and burned fingers there is a print happening in one of our prototype Robox dual nozzle 3d printer units.
This print is the first of its kind, not the content but the method. It has come from months of work on electronics, firmware and software as well as a very simple but ingenious mechanical nozzle change system.

2 different size nozzles operating on a single set of instructions to build an object. Using the fine nozzle for the outline and details while using the large nozzle to fill the parts. There is a lot of fine tuning to do but the test print I can see is progressing really fast. Hours of sketching, theory, coding and design have finally come to this AND ITS AWESOME!

Chris E, Ian H and Ben W, nice work chaps.