eldrick

The Bondtech also has finer control over extrusion "resolution" than Ultimaker versions: it uses a higher number of E-steps per mm of filament. I haven't tried to test the effects of this, but it should result in slightly better feature definition, particularly with smaller nozzles.

The brown spots do indicate degradation from heat. I drilled some holes in the metal cover under the driver area, to improve cooling there.

I use Izzy's design. It leaves good ventilation around the print head, and gives easy access for cleaning it. https://www.youmagine.com/designs/um2-fan-duct

a) use a different duct design that does not get so close to the print-head, b) print it with ABS or polycarbonate, which tolerate higher temps than PLA

Not an Ultimaker employee, but I'd bet you would cook the driver electronics trying to drive more than three times the designed-in power capacity. But go ahead, try it, and the please post a picture of the brown spots on the board where components used to be.

PC needs to be printed at high temps. Set the temperature to 260, and print very slowly - perhaps 20-25mm/sec and you might get through that print.,

I found brown spots on the circuit board around the drivers after a couple of thousand hours of use with the standard 25w heater. I'd say that 50w is a fast way to burn it out unless you arrange for additional cooling.

Keep an eye out for browning on the UM2 circuit board - 50w is twice what the drivers and connecting traces were designed for, and could overheat things down there. I drilled several holes in the bottom of the metal board cover for a bit of extra ventilation while using a 35w heater.

If you use the Tinkercad firmware, the retract and advance speeds are taken care of, and I cannot imagine anyone not using the Tinkercad version. You can also easily set the E-steps with it, so you don't even need the Bondtech file. Repeat - you do NOT need to screw around recompiling the firmware.

The freezer is good advice, but using a putty knife on a hard-stuck part will sometimes take a divot out of the glass, leaving it stuck to the print. You will find whole threads on the topic.

The Cura "Random" option is not even remotely random. If you print a small cone with a slow taper (maybe 50mm tall, with a 5mm taper), you will discover that the "random" locations are aligned in quarter- to half-inch-long segments, leaving multiple very visible diagonal scars on the piece. Apparently the "random" location depends on the diameter of the piece, in a very regular way that is not random at all. So I'll continue using Kisslicer when seam visibility matters.

Random is not always a great strategy for the seam, because it leaves blivets/divots all over all the visible parts of a print. Back is simply silly. Is one supposed to rotate the part on the bed to get the seam where you want it, using Back? Crude. The real problem with the z-seam is that Ultimaker/Cura pretends that it is invisible, so they have not bothered to implement best practices to manage it. Kisslicer is no longer being developed, but it has the best set of solutions for the seam so far.

Cura has never handled the seam well. If you want to control where it occurs and/or how wide an angle it is randomized over, use Kisslicer instead.

Perhaps you could point out that the Ultimakers are safety certified and get the policy changed: Under SAFETY AND COMPLIANCE at https://ultimaker.com/en/products/ultimaker-2-plus/specifications

For anyone concerned about increased noise from the Bondtech feeder, just put 2-3mm of damping material between the mounting plate and the Ultimaker. Felt or sorbothane will work well. I hadn't realized how much noise the extruder motor (OEM or Bondtech) transmits to the frame of the machine. With this tweak, my UM2 is quieter than it was originally.

Consider using Tinkergnomes modified firmware - it adds a lot of functions that would be useful to you in setting up your machine.

Or try Makergeeks.com. The filament I've tried from them is quality stuff, and they are down around US$20-25 for a full Kg spool, shipped.

Real Men & Alpha Programmers don't do documentation.

BTW, with glue or gluestick, soaking the plate will dissolve the glue and release the part, but it takes at least overnight.

Nonsense.

Seriously, why do you have such a hard time understanding that auto-slicing is not something that works for everyone? The only argument I have seen from you is "it works fine for me". Every other argument I have seen from users saying that they want to be able to disable it is something I have faced too. As soon as you do anything more than "load stil" -> "save/print" it's a big hassle. Today I was playing with some small objects in Cura and there were times when the UI did not respond immediately to my actions. It can't be rocket science implementing a setting to disable auto-slicing and add a "Slice me now" button. Get over yourself - if you don't like the way Cura works, use something else. No-one is much interested in your griping about how you don't like a software package you got for free. Try Simplify3D - by paying for it, you get the rights to harass the developers. Or use Kisslicer. It never gets updated, so there's no point in whining about how it works.

You will also find that there is some missing print volume because there is no second extruder, which would be needed to get close to the right edge.

Do you have the current to the feeder motor set to 1200ma? (You can check/set with TinkerGnome's firmware.) If the current is too high, the steppers can warm up pretty quickly, and many people have set theirs up with the stock feeder to increase motor torque and reduce filament slippage.

I don't disagree, but for $100, it might be a fun toy.

Actually, all the issues mentioned in this thread so far have been addressed on their Kickstarter page. For $100, I'm in.