32 bit Upgrade to Ramps!!

I found this on Kickstarter and am in for a 3 pack. I run several printers (transitioned to MKS 1.4 on 3 of them) but this might be a worthwhile improvement to the remaining Ramps/Mega setups and 2x Deltas I’m building. Now what to do with the 3rd board…

I plan to run my MPCNC as a router/laser system and will play around with this board to see if I can get any improvements although so far the machine is impressive as is. The 3D printing community seems to feel a 32 bit board is a huge improvement over the old 8 bit for speed and precision; a lot of discussion on it revolves around Deltas though.

Anyone have experience with 32 bit systems?

https://www.kickstarter.com/projects/1245051645/re-arm-for-ramps-simple-32-bit-upgrade

About this project

The RAMPS v1.4, a simple and versatile shield that sits on top of an 8-bit Arduino Mega that runs thousands of machines worldwide. If you are into DIY 3D printing, CNC machining and laser cutting you have most likely come across or used this board as it is the most popular controller option out there. It does however have limitations, especially with the 8-bit Arduino Mega powering it. This presents a good opportunity for speed and feature upgrades with 32-bit controllers gaining popularity due to its advantages in speed and capabilities. Some RAMPS users are feeling the limits of its 8-bit Arduino Mega MCU specially with Delta 3D printers and high micro stepping drivers.

Tired of slow 8 bit processing, print artifacts and poor LCD performance? Re-Arm for RAMPS is your 32 bit solution.

What is the RE-ARM board?

RE-ARM is a 100Mhz, 32-bit ARM controller with the popular Arduino MEGA footprint. It’s a plug-in replacement for the Arduino Mega in your RAMPS setup for a quick and easy upgrade to 32-bit goodness.

It runs the awesome Smoothieware firmware by Arthur Wolf.

We are not really processor limited on a ramps. The only wall we hit is steps per second(calculation max) on the z axis but if we go any faster we will lose all torque anyway. I guess the easiest way to break it down is we do 2D math with each step, and really only 2 axis at a time, x and y move, then the z steps up, and x and y move doing a trig angle formula with each step. Even with bed leveling on on a 3D printer it is 3 axis but still basic math, no problem.

When you run a delta you are simultaneously doing 3D math on all three motion axis at the same time. Way more calculations. Even then the ramps is fine, its the guys that feel the need to push the speed of there deltas way up, The overclockers if you will. I am not a delta fan so I do not know what the speed limit is on a ramps but I do know we are in the clear by a far margin. Don’t quote me on this but I think the TinyG is the only board running a 4th motion equation on each axis so they need a bit more power, Maybe. We have linear accel, the tiny g has s curve accel…nice…

It would seem to be a Delta specific thing and even then may not be necessary. I’ve played with speeds on my Prusa style printers and there’s an upper limit to quality that’s nowhere near the speed max and is highly dependent on the filament material. Running faster just isn’t practical so if that’s the only benefit, it’s likely not worth the hassle. 32 bit sure seems to be the buzz words of the moment!

I used to build gaming PCs and try overclocking everything to the point of implosion just to see how high a score and max FPS I could get on the benchmarks… running the machines at those settings for any practical reason proved pointless though when 30FPS was good enough for most games. I guess it boils down to bragging rights over usefulness.

Exactly…but careful. There are some people that don’t believe in physics or something and say you can print as fast as your machine will go with no loss of quality or strength. I stopped arguing with them. I feel layer need time to bond together, and overhangs need time to cool between layers.

If you search there are even a few threads here about it. But man, if you look at some of the delta speed threads …jeez it gets ugly. For me the highest strength I get is about 30-35mm/s PLA, above that I feel layer bonding starts to suffer. This is all my personal opinion, just so no one gets all huffy puffy about it.

People who say they get 500mm/s on a delta (or something like that) are not actually timing it. Acceleration limits the speed you can attain in practice. Smoothie is pretty awesome from a convenience standpoint though – especially in the ability to set the stepper current in software. You can get an MKS Sbase (Smoothie clone) with DRV8825s built in for $50, so I don’t really see the advantage of using a crappy RAMPS board on top of it for the same price, especially when you lose the ability to set current in software.

Well, the E3D folks claim prints with big layer height not only print faster volume wise, but have greater strength.

As I’ve mentioned elsewhere, I switched to a volcano, and started printing all my parts with a layer height of 0.6mm and a layer width of 1mm.

I finished my prints some time ago (rest of work delayed by house move), with a total time of around 28 hours, and they are insanely strong. When I take for instance the XYZ part, and try to twist it hard with both hands, at 0.26 layer height with a standard nozzle, I can hear the cracking sound of delamination. With the volcano printed part, it is clearly more rigid and resistant to this shear force.

The the most plausible claim I’ve heard is that wider layers give greater inter-layer bonding. See this video from 7:48 for a semi scientific test of layer adhesion at different layer heights.

Nozzle size is a whole different subject.

I am able to print two xy pieces in 15 hours with a .5mm nozzle, and not changing the movement speed at all. Nozzle diameter physically lays down more material increasing surface area and contact time. With a .5mm nozzle I can turn up the speed and still keep the same contact time because of the increased surface area and the increased volume carries with it more heat capacity, I agree because physics agrees.

I forgot to mention, I’m using the 1mm nozzle for that 0.6mm layer height.

To me it’s been a revelation, because I’m far more interested in printing mechanically functional parts than parts that look smooth.

I’m just curious why you haven’t gone right up to the 1mm nozzle or beyond for your stock parts. Very few of the parts (tool mount and top/bottom corners) have required lowering of the layer width to print successfully.

Hello Vicious,

Happy new year everyone,

I was reading your reply over here (November 14, 2016 at 8:18 am #20964) about the calculations/microsteping/torque.
Could one way to get more steps per second and holding on to torque be upgrading the stepper motors to 0.9 angle instead of 1.8?

I saw some that hold 58oz/inch and even 66oz/inch. This is Less than the 76oz/inch in your bundle, but they take 400 turns instead of 200 on a full revolution.

If micro stepping loses torque and precision, would this actually mean that we could get a better balance between precision/torque?

Just a thought,
Joao

This might interest you then

https://oshpark.com/shared_projects/lTd6zhHq

Links and everything above, runs teacup but at 32bits it should be FAAAAAST!

In my opinion, the only case it could be useful to get more computational power would be if we wanted to make some kind of position feedback on our machines, to go from passive steppers to close loop control.

I’m not sure Marlin or any open source firmware can handle this?

I’ve been testing with the arduino with the ramps 1.4 and it isn’t fast enough. I also have the re-arm and got the motors working. This is a good start and it is FAAAAAAAAAAAAST.

I need the motor speed for my 100w laser project (also on this forum). For engraving i need more speed.
I made a movie from the quick test. I will try to get that online so you can see the difference.

Did someone get the rest working as well?
I got stuck on the pwm ports (for the laser)

I have the ramps speed firmware limited. Stepper power drops off dramatically at above 60rpms for all the nema 17’s I have looked at. If you need more physical speed you have to do it with larger pulleys, not by turning the stepper faster. But you really need to move faster than 190mm/s?