The TAZ Pro has two extruders which allows me to try and use dissolvable PVA support. Support is simple enough but hard to remove from the print cleanly, so using PVA allows extra options - just dissolve it!
I have had to play with the Simpify3D settings a bit as the settings for the TAZ 6 did not quite work. I am not sure if the bed is different, the nozzle, or what but my prints were almost welded to the bed. I have tweak the settings for nice clean prints with nGen now. The next challenge was settings for PVA supports.
I ordered some from RS (yes, the price was not silly, strangely), part 174-0082. Well, actually I ordered from someone else, and realised wrong diameter, after opening it, D'Oh, but now I have the right stuff I googled a bit to find temperature.
It is funny stuff, and I ended up printing at 205C which is apparently on the high side. I could also see from simply feeding the filament that it came out thick and slow (around 1mm).
The key setting needed to stop it just curling up was speed - it needs to be very slow. In the end I ran with 2x multiplier, 1mm wide, 20% print speed, and that actually worked. Well, mostly (the eyes went a tad wonky, but worked).
For a start, the PVA comes away from the model really easily, so that is a good start.
Then, put in warm water for a while to remove the last bits, and yay, it worked.
Now to try something more complex with enclosed parts that simply could not have been printed before.
I have been 3D printing for a long time - and even coded a slicer once.
I have tried many printers. My current favourite for cost and performance is the LulzBot TAZ. We have a TAZ 6 at the office and (even though not on the A&A web site) we do 3D printing if you want.
It is a nice heated bed, which works well, especially with my filament of choice ColorFabb nGen.
I have been using to make cases for various electronics / R&D.
Sadly I slightly fried my TAZ 6 units. I have a new controller board on the way, but decided to check what they have now, and saw the TAZ Pro. So I ordered one and to my surprise it arrived in a couple of days (in spite of warnings of back orders and long lead times). Nice.
It is nice...
But is it worth the price (around £5k)?
Well, possible. It has some nice features and works very well. I have only been playing with it for a day now, but I can make some comments. The bed levelling is faster and seems more consistent. The Z axis is belt driven meaning it can easily use Z moves when moving from one part to another (far too slow when Z axis is screw). The big thing is the dual extruder.
Cura?
LulzBot recommend Cura, a good, free, 3D slicer. It works well, and makes some impressive prints, but...
It seems way slower than I am used to (I used Simplify 3D before)
The prints, whilst nice, and precise, seems brittle. I expect minor tweaks to settings would help.
It expects nGen to be glue sticked to the bed - and I know it can be printed without, but needs hotter bed for first layer. I tried that and it worked.
Somehow the prints were distorted. I am not sure if cooling is right. I am sure it could be tweaked.
However, it did work, as I say. And the reason I tried it is that Simplify3D, which I was using, had no profile for the new printer.
But, Simplify3D support emailed me one, within a few hours of asking. It works!
Simplify3D
Whilst I do not usually end up recommending paid-for software, this is good. It works well. It is way faster. It is not perfect, but nothing it, but it is nice to use. So I recommend it.
Dual Extruder
This is the first time I have used a dual extruder. But the TAZ Pro does it really well. The heads are motorised to retract completely out of the way. The full bed size is still available to both extruders. It really works well.
There are several reasons to use a dual extruder.
Two colour prints - obviously. To be honest this is a pretty minor use case. But it works well.
Mixed materials - combine fixed brittle material and flexible rubber to make complex designs - not tried it yet, but fun possibility.
Using dissolvable supports - this is likely to be the main use.
The dissolvable supports will be subject of another blog when the PVA reel arrives. Basically, 3D printing like this cannot always print what you want as some things are "in mid air". Using support material works, but has to be cut/broken off, and is impossible to do "inside" some designs. Using dissolvable supports allows the impossible to be printed, and then put in warm water for a while. I look forward to it.
The dual head working is impressive...
In the mean time - two colour test print...
Any downsides
The only one so far is the heads are covered by a safety guard with warning about being hot - which means you cannot see what is printed as it prints. Ironically it means you cannot see the print head, and can end up burning your finger when trying to adjust something because you cannot see where your finger is. Elf 'n' safety gone mad, IMHO. If it always "just works" then I guess it is not a problem. TBH they should have designed with angled plastic to make a guard that allowed viewing of the actual print head. This may seem trivial but I do feel is more important than they realise. Even ignoring the practical aspects of knowing a print is not working right ASAP, seeing what is being printed it important for selling the whole idea of 3D printing...
