Bigtree Tech disappointment

I bought the SKR 1.1 Pro with TMC 6150 drivers from them which looked like a good deal. Sadly i ran into trouble when the board did not work as advertised. Even though i tried Bigtree Techs own Marlin fork as well as the official one it refused to work. [reprap.org]
I contacted their support, which i had to do already because they did not send the drivers on first try, and got a fast but completely useless reply.
Since then i am stuck in a loop of them asking for my configuration and me pointing them to my fork of their Marlin version.
The SKR 1.3 i got at the same time thankfully forks fine.

I wonder if their good rating on Aliexpress is a fake or my trouble a fluke.
Do you have any experience with them?

Cheers
Björn

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

With "good deals", so often you get what you pay for. A genuine Duet 3 would have given you 6 TMC5160 drivers built in, web server and Ethernet port, optional dedicated link to a RPi, 240MHz ARM M7 processor, almost unlimited expansion via CAN bus, firmware configuration without rebuilding the firmware, and - most importantly - support. But I expect you paid a lot less for your SKR.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Is the Duet 3 available now? It wasn't when i was looking for a new board.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Quote
Srek
Is the Duet 3 available now? It wasn't when i was looking for a new board.

The first batch went on preorder last month, but has sold out and is shipping now. We'll probably open a new pre-order soon for the next batch, which will ship in November. The first production expansion boards will ship around the same time or a little earlier.

Realistically, Duet 3 is overkill for most 3D printer users, which is why we're continuing with Duet 2 production. We're planning to refresh the Duet 2 design next year.

Here's a snap of my current Duet 3 test setup (main board + 3 expansion boards). I must get more stepper motors, so that I can test a system with more expansion boards!



Edited 1 time(s). Last edit at 09/13/2019 11:42AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
Do you have any experience with them?

I have tested the SKR 1.3 board and I liked it a lot using Marlin 2.

However, I have not interacted with them.

I like that SKR 1.3 does include both serial and SPI wiring on-board for several types of TMC driver chips.

My guess is with companies like this the support is you.

The 1.3 works fine for me as well, it is only the 1.1 Pro that doesn’t.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

So far it seems that the SKR Pro does not get along with a high Z step count. If i use the correct number of steps i have to reduce movement speed to make it work.
Maybe the board is just to slow to process the number of steps/mm i need (6464) at normal movement speed.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Quote
Srek
So far it seems that the SKR Pro does not get along with a high Z step count. If i use the correct number of steps i have to reduce movement speed to make it work.
Maybe the board is just to slow to process the number of steps/mm i need (6464) at normal movement speed.

Is that 6464 steps/mm for X and Y? If so then I am not surprised. Movement at 100mm/sec would require >600k steps/sec. On Duet 2 we reckon that 200k steps/sec is about the limit for a 120MHz ARM Cortex M4 processor. But I'll see whether Duet 3 can do better.

Why is your steps/mm so high? Are you using high native microstepping perhaps? Or fine-pitch leadscrews?

Edited 1 time(s). Last edit at 09/22/2019 02:25PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

No, for Z. It is M8 rod with an additonal belt reduction on a 0.9° stepper.
It does not seem to be the only or even main problem though. While reducing homing speed does resolve the initial issue of Z not moving after initial homing try there seems to be another issue. Whenever a certain speed is exceeded the motors become non functional. For some reason the board processes the first Z move at a way to high speed and goes about 5mm to far G1.
Z0.18 F300 results in a very fast Z movement to ca+5mm
As for the Duet 3, i still can't find any sales options, can you please include a link to a shop that has it available.
Cheers
Björn

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Check out the Kilpper Firmware.

I've installed on an Ender5 (128p 8-bit controller) and it's pretty good. You'll need a Raspberry Pi on the system too, but OctoPi gives a pretty nice Web Front End, and you can plug in a Webcam.

I've heard it can achive higher step rates than standard Marlin (I think the Klipper Firmware doesn't actually parse the GCode, so it can focus simply on motion and control. The Raspberry Pi parses the G Code and then creates lower level commands to be sent to the Controller.


I also have the Duet3D, it's a totally different beast from the 8 bit stuff, but there is a price difference... Seriously check out Klipper though, it's made my Ender5 quieter and prints appear to be slightly better.. but that could just be placebo! lol


I also have the SKR (non Pro) and specifically wanted the better stepper drivers so was very annoyed to find it's still a matter of hacking stuff. I'm easily capable of doing that, but I simply don't think that should be needed.

I used this video for installing Klipper:
[www.youtube.com]


Main website;
[www.klipper3d.org]


I'm not involved in the project, I read about it on a Facebook group a few months ago and decided to try the Ender with it.


I've not opted for the Duet3D for the Ender5 as I'd need to design a mounting plate, patch the cables and expect the Wifi reception would be poor as the base in fully enclosed Metal (and earthed).

"I also have the SKR (non Pro) and specifically wanted the better stepper drivers so was very annoyed to find it's still a matter of hacking stuff. I'm easily capable of doing that, but I simply don't think that should be needed."

Please elaborate on this statement. What drivers and what hacking is required?

I think he refers to the need to do explicit wiring for the 6150 on the SKR 1.3. The 1.1 pro only needs jumpers set to make the 5160 work.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Nice, Bigtreetech told me that their board does not support Dual X, which sounds like a lame excuse to me.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Unsurprisingly they went back on that statement and gave me some changes to pins.h that actually made a difference. It only shifted the problem though.
Now z homing works fine, but the moment i execute gcode from file Z does not move. If i manually enter gcode all axis including Z move fine, it is only with printing from file that z does not work. This not only happens if i print from SD card but also when i print a file via repetier host.
I'm stumped

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

That is a common issue of badly configured firmware, and is quite Independent of the controller

Your Z max feed rate is probably to high

The control panel sends a G1 Z?? F?? where the feed rate is slow.
but when you print from USB or SD the Feed rate is inherited from when ever it was set last

find the section of configuration.h

/**
* Default Max Feed Rate (mm/s)
* Override with M203
* X, Y, Z, E0 [, E1[, E2[, E3[, E4]]]]
*/
#define DEFAULT_MAX_FEEDRATE { 300, 300, 5, 25 }

change the Z value (5 in this example) to a lower value 3 or 2.

Edited 1 time(s). Last edit at 10/27/2019 07:12AM by Dust.

THANK YOU!
I have no idea why this only happens on this board, i have three other printers running marlin 2 on a SKR 1.3 or RUMBA and i never had this problem.
Some initial movements are in slow mo now, but i can live with this in exchange for a working printer

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

If your acceleration is slower and or your stepper driver current limit is higher you can achieve higher feed rates. Depends on your hardware...

I'll have to check, this is the first time i use the 5160 drivers. The thing that wonders me most is that the exact same printer worked fine with a RADDS, until i had an electronics failure and had to replace the board. I used the same basic settings for speed and acceleration i used with the RADDS and with the RUMB in the second identical printer. Due to that i never thought that speed or acceleration might be wrong.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]