It has been a little while since we last updated you on where we are with the dual material head, but I hope we can be forgiven for the lack of communication – especially as the real reason for this is that the entire CEL team have had their heads down testing the latest prototypes for faults, fact finding, and future proofing.
But we feel an update now is timely, as we are getting so close to being able to launch the new head to market; we really are almost at the end of what feels like a very long development journey.
Software is the biggest challenge as there really isn’t a good dual material system on the market to use as a template and both the slice engines we currently use aren’t able to deal with dual material prints in a consistent manner. This means we essentially had to start from scratch creating innovative software for this particular hardware development.
Before we get deep into the dual material system progress it’s worth mentioning what we’ve done to the software in preparation for this momentous task.
For the release of AutoMaker 1.02 we spent a good amount of time restructuring and developing the post processor. We gained a much better understanding of where and how to open and close the needle valves, how to integrate the material the needle ejected into the model and how this is going to affect dual material printing.
For the upcoming version of AutoMaker we’ve actually recoded the post processor from scratch, our new level of understanding was restricted by our previous work. This updated thinking has gone into the current version of AutoMaker and is the backbone of dual-material capable AutoMaker version 2.
Right back to dual material and where we are now….
There are a lot of new requirements needed to take a multitude of models and turn them into a multi material print. We wanted the ability to take a 3D model, break it into individual parts and allow the user to easily select which part was going to be assigned to which material.
Because most models which require multiple materials will need two or more separate parts, we wanted to add Group/Ungroup and model splitting. The Group/Ungroup and model splitting all have to be combined with the original transform functions so that we keep the parts’ relative position.
After we started to look closely at the model files AutoMaker was expected to handle we found a very high percentage had imperfections – not normally a problem as the slice engines do some simple repair work – but a bigger problem if you’re trying to bisect the data and then add back in the missing vertexes, polylines and faces. We’ve not fully finished this aspect of the software and currently only warn users of the imperfection in the models that may cause problems later.
We now have a software tool that allows us to perform all of the above functions and it’s helping us finish the development of all the hardware.
The development of the software will continue up to and beyond the date you receive your new hardware, but for the first version of AutoMaker which is capable of doing dual material prints we have tried to keep the functionality to a minimum so that we can ensure stability.
After a few false starts we’ve now got working dual material heads and an innovative second reel holder complete with reader. We are also taking a very close look at the management of the Bowden tubes and cables between the x-carriage and chassis.
We were worried that the differing flexibility in filaments would affect the homing accuracy and thus distort the mapping of the bed giving poor first layers. We’ve made a fancy new cable chain to take the data and power cable and slightly constrained the Bowden tubes which now both reference the X-rails rather than the carriage.. (sorry if this is too geeky), basically we have more stuff to help improve probing and tidiness.
Another thing that only the people in the know would notice is that we have added a USB socket into the build chamber. It’s been there from the beginning – hidden away in the centre of the reel – but we’ve never got round to exposing it. We thought as we were designing a new PCB for the dual reel holder we would add the missing plug so you can start playing with it too.
The needle valve system has been extremely important in the quality of printing that Robox can achieve when talking about single material prints, removing all the stringing from one island to the next. When you use this innovative system with a dual material head it starts to become even more impressive.
All the dual material prints we’ve seen from other manufacturers have to include some sort of wipe tower, ooze screen, long cool down / heat up period, or purge sequence. None of this is necessary if your print head can stop the flow of material at its nozzle tip like the Robox can. Our very first print from the new system was one of the best we’ve seen. So now we’ve worked out how the system works, we’ve got working samples, and we are producing great print results.
The final step is to ensure that all materials will flow through the new hardware smoothly, tidy-up the interface and test, test, test… I can’t tell you how big a chunk of work this last section is. We need to try every single combination of user input and output and not just once, on one machine. This needs hundreds of times on many printers by many different people to ensure that all the logic we’ve put into the software and hardware doesn’t crumble when given to a user who hasn’t been involved in the development. With this in mind we’re now at the stage where we’re asking some of our customers who have placed pre-orders to beta test the first batch of hardware from the final production line.
So all in all, we’re really, really close. If it sounds like we’re no further forward than last time – bearing in mind we finished our last update by saying we were “testing, testing, testing” – please be assured we are. But after testing comes tweaking, and then more testing!
So the final date is……???
We can’t say for sure, at the moment things are looking great and we hope to be able to launch the dual material head end of November, as per our last post. If not then, early December. But to reiterate the sentiments we made last time, we will only release the head if we’re confident it’s going to produce excellent results for everyone.
THANK YOU once again for your unwavering support, stick with us, as in just a couple of months the Robox 3D printer will make its mark as something completely different from anything else out there on the market – and we want you there with us to enjoy the ride.
Oh you want a picture of a dual material print? Well….here is a sample of what we have to come.