They prevent the loss of magnetism that happens in ferromagnets when temperature rises above their max working temperature point, until it reaches its curie temperature and completely demagnetizes.
Most motor magnets have the working temperature limit somewhere in the 80-160 range. Its never really stated properly and I wouldn't trust Chinese motors to use the proper materials.
You might want to check the temp rating on the linear rails. Most of them are rated around 85c and the plastic parts are nylon which melts at around 120. It's possible the thermal expansion binds them beyond that.
You'll also want to use grease that works at high temperatures and doesn't melt away.
In a cnc program you want to adjust your toolpath based on measurements. So in one point you might see that the features are slightly too small. So you add cutter comp to cut a tiny bit smaller. You can also use it to walk your holes to a specific tolerance(for example). Add cutter comp to undersize the hole. Then walk back the offset and repeatedly run that program segment.
Cncs are not accurate like you imagine 3d printers to be. The machining process often requires fine tuning to get proper results and continuously regenerating the program is very slow and unnecessary. Just better to change a single value on the console and get on with it
3dprintingnerd has a video on YouTube that shows the bed a bit better. It's basically individual pcb heaters with their own thermistors hooked up to a central "hub" that's under the bed. It also allowed things like segmented heating, hotspot measurement and compensation and heating only specific areas of the bed.
It's a pretty neat concept, albeit a complex one.
Lacks a 3 post leveling. A pretty basic feature.
Worth it is a very subjective term. One basic thing those people trying to make their printers very fast is that the easiest way to remove vibrations is to make your frame heavier. Just by adding enough mass to the frame you can make a print head of several kg move at 1000mm/sec.
Just ask essentium. Or pnp machines.
i didn’t mean actual stewart platform, just the kinematics of it since what you’re trying to do is mathematically very similar to it with the two platform rotation axes.
Anyway, a 3 dof parallel platform is a simpler stewart platform. In this diagram, You can count the x1 and y1 rotation axes and you get the height of the point B from the I actuators and trigonometry.
If you look at this Instructables link, i’d think you get what you want when the T vector is the height and is constrained to the base Z vector.
At least thats my understading of the math.
Have you though about looking at Stewart platform kinematics? It's a pretty similar in concept, it just has more movable axes.
Not true. In CNC world the 5 axis programs are supplied as tool vector coordinates (X, Y, Z for the tip, I, J, K for the vectot point) and it's the machine itself that applies the appropriate transformations to run the machine. The CAM software doesn't need any machine specific information to create the code, though specific limitations of individual machines are not taken into account(there's Sim software for that).
The same approach would have to be done on th slicer in order to not lock it for a specific machine configuration that it's designed for. You're right about that.
Linuxcnc is a machine controller, like duet and RRF. The G-code is largely the same, aside from some codes that might be specific to machining or 3D printing. If you had a slicer that would output a 5 axis G-code with the standard tool vector co-ordinates, you could build a 5 axis printer with linuxcnc. Though it’s missing the more advanced 3D printing focused features.
a non-planar printing is simply anything that uses the 3rd axis while printing to create non-planar layers. techically mesh bed compensation falls in to that. kind of. though its not printing non-planar layers.
there is already a fork of slic3r that does non-planar printing. some guy did it as a masters thesis in germany a few years back. People have made machines for 5 axis printing, or a tlting bed printers. Mostly for university work. They just aren’t usable in the real work because there’s no slicer to run them. i don’t see it as a chicken-or-egg problem because the hardware has never been the problem. Making the 5 axis hardware is quite easy. Even the matrix transformations for a 5 axis 3d printer aren’t that complex if you use the BC trunnion method, which mostly comes down to two matrix transformations since no work offset coordinates are needed.
Linuxcnc actually has that, has had for years. It’s just not very usable in a machining context and there’s no slicer to try it with a 3d printer.
3D printing didn’t really kick off until a workable slicer emerged. Its the most complex problem to solve.
thats honestly the wrong way to go about it. The slicers would need to be developed first, then the hardware. A normal 3D printer can already do non-planar printing. There’s no modifications required(though you would need a special nozzle for optimal performance). for a true 5 axis printing only a simple trunnion with 2 motors is needed. which is trivial to make with a 3d printed parts .
I get it, im more of a hardware guy myself. But this really is putting the cart before the horse(or climbing a tree ass first as we say). We’d need slicer support before any hardware work is really usable. and i dont see any work being done on that front. If i remember the slic3r maintainers were quite hesitant to bring the non-planar slicing work into the mainline slic3r. which is a shame.