I feel obligated/compelled (mostly compelled, sorry) to point out that these are not speed controllers per se, but voltage regulators. Speed controllers would include some way of measuring the RPMs of the spindle, and feeding that back to the controller. It will slow down the router, but don’t fool yourself into thinking you’ve gotten actual speed control. Even the 30K RPM of the DW660 is no-load speed, and can’t really be considered a reliable speed under load (although DeWalt does a pretty good job with their controls). If you look at the speed controller project here, you’ll see that it’s non-trivial, and requires some surgery on the tool in order to jerry-rig a tachometer in there, and then get the feedback loop right. It’s another microcontroller just to manage the tool speed.
And yes, I’m picking nits, there’s no need to point that out to me. These voltage regulators work well enough for most of our performance envelopes, so it’s not really a critical deal, even if you’re talking about cutting plastics and metals.
A potentiometer would waste a ton of power and heat up with hundreds of watts and burn up. An SCR based dimmer switches on and off quickly so it’s fully on or off but only a percentage of the time.
There’s a balance with all three. The main problem is heat and stability.
If you can’t slow down the speed, you can get away with increasing feed and decreasing DOC/WOC… To a degree.
FSWizard (app) says you can go 20000 Rpm (but that’s with flush coolant) with carbide 4 tooth. 30000 is a bit scary. I say scary because since aluminum gets gummy and can grab the tool. I’ve had parts rip right out the vice because of this. 30000 is fast, will get hot and might just grab your part of you’re not keeping it cool and clean off chips
Is there any rigidity improvements on the z axis? Is the hole pattern in the conduit the same? I am putting the primo core on my machine and know the z axis is interchangeable. Is there any point to me having the new one?
Does Universal Gcode Sender work with Marlin? It looks like a really useful software. I could flash grbl to my ramps, would grbl make spindle speed control easier? Is it harder to setup or use? Right now I plan to control my spindle with the fan gcode on Marlin but if on grbl I could use the dedicated spindle speed control that would be great.
Edit: Found a grbl build. I think I’m gonna use it, flash and test it now real quick.
I’m not using a RAMPS board, but I found setting up spindle control in grbl very straightforward. Haven’t cut anything yet, but have tested variable speed and the tool noise changes when I play with the RPM buttons in cncjs.
There is a “Spindle & Laser control” section in Configuration_adv.h
I haven’t done this (yet), but I think you need to uncomment #define SPINDLE_LASER_ENABLE then flash the firmware. Maybe someone with more experience can add details.
It’s some deep Eldritch magicks that Jeffe and Anttix conjured up that will auto-build Marlin based on certain config files. If a certain configuration is deemed popular or common enough, it could be blessed, and get an auto-build config. Then, anytime they pull the newest build from Marlin, or apply a custom patch while waiting for a PR to go through, it will automagically rebuild Marlin for all the configurations.
