Scara Setup

Dougal1957

@DannyDefe:

No problem with testing, we just installed Duets on the large scara.

I have implemented continuous rotation and my simulations on a bench set up (not an actual printer) seem to indicate it is working. So please try the 1.21RC2 release when it is available a few minutes from now. To enable continuous rotation of a joint, set the min and max angle ranges for that joint in the M669 command such that max - min > 360. Then the min and max values won't be used to limit the travel, however one of them will still be used to determine the position when homed.

David

Are you close to committing this yet have seen the Whatsnew.md but Git is still showing 1.21RC1

DannyDefe

David I was able to reduce the steps per/ degree down to 736. You were correct because after adjusting some parameters I was able to hold connection over WiFi and complete the Homing sequence. The scara moves at a good fast rate during the Homing sequence, but now the problem is as soon as the print starts it slows down to less than a snail's pace. No matter what speed I set in the g code it just barely moves , it's as if the processor is choking. What do you think

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dc42

Please post your config.g file.

DannyDefe

; SCARA #2SHOP
M111 S0 ; Debug off
M550 SCARA ; Machine name and Netbios name (can be anything you like)
M551 Preprap ; Machine password (used for FTP)
;*** If you have more than one Duet on your network, they must all have different MAC addresses, so change the last digits
M540 P0xBE:0xEF:0xDE:0xAD:0xFE:0xED ; MAC Address

;*** Networking
M552 S1 ; Turn network on

;*** Ethernet networking: Adjust the IP address and gateway in the following 2 lines to suit your network
M552 P192.168.1.14 ; (0 = DHCP)
M554 P192.168.1.255 ; Gateway
M553 P255.255.255.0 ; Netmask

M555 P2 ; Set output to look like Marlin
G21 ; Work in mm
G90 ; Send absolute coordinates…
M83 ; ...but relative extruder moves

; Disable Fan 1 thermostatic mode

M584 X5 Y6 Z7 E3 ;Set drive mapping
; Axis and motor configuration
M569 P5 S0 R0 T4 ; Drive 0 goes forwards X
M569 P6 S0 R0 T4 ; Drive 1 goes forwards Y
M569 P7 S0 R0 T4 ; Drive 2 goes forwards Z
;M569 P8 S0 R0 T4 ; Drive 3 goes forwards E
M569 P3 S0 ; Drive 3 goes backwards E
M669 K4 P453.75 D458.75 A-90:90 B-156:156 C0:0:0 T1 ; set SCARA mode and parameters
;M669 K0;

;Endstop configuration
M574 X1 Y2 Z2 S0 ; M574 X2 Y2 Z2 S1set endstop configuration (all endstops at high end, active high)
;*** The homed height is deliberately set too high in the following - you will adjust it during calibration

M666 X0 Y0 Z0
M208 S1 X-90 Y-126 Z-1 ; Axis minima
M208 X90 Y1156 Z150 ; Axis maxima Z WAS 100 ; put your endstop adjustments here, or let auto calibration find them
M350 X1 Y1 Z1 E16 E2 I1 ; Set 1x microstepping with interpolation
M92 X736.36 Y736.36 ; Steps/degree for proximal and distal joints M92 X415.726492 Y273.504273
M92 Z6600 E350 ; Steps/mm for Z and E
M906 X0 Y0 Z0 E1500 I60 ; Set motor currents (mA) and increase idle current to 60%
M201 X100 Y100Z1000 E1000 ; Accelerations (mm/s^2)
M203 X1000Y1000Z5000 E1000 ; Maximum speeds (mm/min) 1000
M566 X10 Y10 Z500 E1200 ; Maximum instant speed changes mm/minute

M581 Z1 S1 C1 ;Configure external trigger

; Thermistors
;M305 P0 T100000 B3950 R4700 H30 L0 ; Put your own H and/or L values here to set the bed thermistor ADC correction
;M305 P1 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set first nozzle thermistor ADC correction
;M305 P2 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set 2nd nozzle thermistor ADC correction

; Tool definitions
M563 P0 D0 H1
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R00 S00 ; Set initial tool 0 active and standby temperatures to 0C

M92 E663:663 ; Set extruder steps per mm

;*** If you are using axis compensation, put the figures in the following command
;M556 S78 X0 Y0 Z0 ; Axis compensation here

M208 S1 Z200 ;M208 S1 Z-0.2 ; set minimum Z

;T0 ; select first hot end

; Pressure advance
;M572 D0 S0.5

; Misc
M83
M117 Use https://configurator.reprapfirmware.org/ to set up your printer config
M302 P1
M563 P0 D0 T1 ;enable cold extrusion.

; Heaters
;M143 H1 S260 ; Maximum heater temperature
M140 H-1 ; No bed heater
;M305 P1 T100000 B4138 C0 R4700 ; Thermistor parameters for heater 1
;M307 H1 A577.0 C199.0 D9.8 S1.00 B0
M665 H100
TO

DannyDefe

Did you get a chance to look at my settings, it's been awhile

dc42

Hi Danny,

If you send normal G1 commands (no S1 or S2 parameter) from the command line to move the head in X and Y, what speeds are you able to achieve?

DannyDefe

I'm able to achieve relatively high speeds, so it's completely different when it starts to run the program , it as if the processor can handle it.
Like when I'm homing or moving into position to start the print

dc42

Please share the GCode file you are trying to print.

DannyDefe

link to g-code

https://www.dropbox.com/s/vsrvgqxz7i9x0yo/cyln1%282%29.gcode?dl=0

dc42

What I can see in that file is that your extrusion amounts are huge compared to the normal range of 3D printing, around 60000mm/min or 1000mm/sec. However, in the config.g file you posted earlier, the maximum extrusion speed in the M203 command is 1000mm/min, which is only 1/60 of the speed you are calling for. No wonder it moves slowly!

So the first thing to check is whether you have entered the correct units in your slicer. Perhaps your slicer is commanding 60x the amount of extrusion that you really want. For example, the first extruding move in that file commands 0.5mm of XY movement and 6mm of extrusion. Is that what you intended? If it is, read on.

If you increase the maximum extrusion speed in M203 to 60000 or greater, you are likely to face three further problem:

1. The acceleration limit (1000mm/sec^2) in your M203 command means it will take a whole second to accelerate up to 1000mm/sec. So you will need to increase acceleration, assuming your extruder hardware can support higher.

2. Your E steps/mm is 350, so at 1000mm/sec this would require a step pulse rate of 350kHz which is right at the limit of the maximum pulse rate that a Duet WiFi/Ethernet can provide when only one motor is moving. So I suggest you reduce E microstepping to x8 or x4 in order to reduce the steps/mm.

3. At such high motor speeds you may lose torque. Use the motor speed/voltage calculator at http://reprapfirmware.org/ to check whether you have enough drive voltage to maintain extruder motor torque at the extrusion speeds you are looking for.

DannyDefe

David I'm using hybrid steppers so the voltage is not a problem because it has external power supply to the steppers. My minimum counts per Revolution is 800 selected on the hybrid steppers, I can't go any lower. So I don't use microstepping

The extruder High count might be misrepresented, I generated this file and that was left over from a print that I did on another platform. But I'll definitely check and make sure before the next test. Unfortunately I had to break it down because we have to go to a large show coming up in Pittsburgh. So I had to go back to my old platform.

DannyDefe

David
I'm back after the show and would like to get this up and running. I have a complete installation on the big Scara now.

All of the extruder speeds have been corrected but it essentially does the same thing. It homes perfectly at relatively high speeds without a problem. Then it starts to print and everything slows down, the distal arm just slowly comes in and crashes.
links included the G-Code and a photo of the board installation.

The prox switch is worked exceptionally well so if anyone else needs a 5 volt switch I would recommend these. We need the prox switch on the proximal base in order to do continuous rotation.
[[url]https://www.dropbox.com/s/lp2tysdk2q5g7ff/20180326_170037.jpg?dl=0]

[[url]https://www.dropbox.com/s/3sir48tk8nz2xfn/20180326_170049.jpg?dl=0]

[[url]https://www.dropbox.com/s/35qs8g7ggpwc7dt/56 TEST.gcode?dl=0]