Well, many many months later, and having advanced ginormously in my 3D print / printer knowledge, I have some commentary to add to this thread I started.
First, Brent is a superb employee, and has been extremely helpful to me. A few criticisms of AO’s product and marketing strategy that follow do not reflect at all on the rank and file personnel, who were fantastic before the closure.
First, the pertinent feedback now that I’ve done a ton of printing in brass, copper, bronze, and steel: I can complete complex prints with a nozzle as small as 0.35, but IT IS EXTREMELY FINICKY!!! You will need to go through an experimentation process with any nozzle size below 0.5, for your printer, to tune speed, flow, temperature, retractions, to get it to print successfully without clogging. If it’s going to clog it usually will within the first 30 minutes or so of a print.
Similar for wood filled filaments – same tuning process. However, the relationship between temp and flow rate is even more sensitive here, as too hot, or too little flux (flow rate) can result in the wood particles cooking (too much) and therefore burning, then clogging the nozzle.
For wood, the time in the melt zone, and temperature, control how much the wood material “cooks” and darkens. This is really useful for varying the color of the extrusion a little bit using print speed as a way to control the time in the melt zone. However, too hot and too long, it will burn and clog the nozzle.
Criticism of AO Product strategy
I was rather pissed off when, after learning enough to no longer be a noob (I’m an engineer as a starting point), that I was tricked into spending hundreds of $$ on another “print head” to get 0.25mm extrusion widths.
You see, the cautions about changing nozzles in the documentation for the Mini 2 (and every other printer) is just complete BS. Total. AO tries to scare the complete noobie that removing and replacing the nozzle is really advised against, but if you do make sure you have special tools (torque wrench) and hot-tighten to 30 in-lb.
The bit about the tool and properly torquing are correct (although 30in-lb is a bit too much for E3D brass nozzles – 26 much better). While there’s plenty to learn first about changing a nozzle, it better not be anything more technically sophisticated than what you’re ready for, or you’re really not going to be doing much with your 3D printer – you’re too unskilled and ignorant of basic things you’ll need to know simply to use it for much at all.
Okay, so anyone that wants a different nozzle size to print with, go for it! Go to E3D’s website and order a bunch! Basic brass nozzles are just under U$6. Get every size! I decided to upgrade my heater block to nickel plated copper, and went ahead and got every size of plated copper nozzle (they’re about 2x the price). I’m am VERY GLAD I did this. I change nozzles all the time to best suit what I’m trying to print, the detail, desired resolution and quality, etc. In this way I can perfectly balance these variables, as well as speed and material use.
The SL print head got used a few times until I got savvy to how NOT delicate the machine was, did some googling, and dove in. It has since been cannabalized to fix my original printhead on a few occasions.
Man, if you can’t remove a nozzle I don’t know how you’re going to do anything more involved than printing Hello Kitty keychain dongles. Anything interesting is going to eventually result in a clog, jammed piece of broken filament in the heatbreak, or a dozen other things that happen when you branch out beyond Hello Kitty.
AO, ya been bought now, so this is really all moot. Still, it was about the worst thing about the company, really just a ripoff. $400 to get a $6 nozzle from Lulzbot instead of E3D. Not good.