Delta Radius VS Printable Radius? Duet Setup

[Qdeathstar]

Hi,

I did try google for this but, what is the difference between delta radius and printable radius? I know i can print a 190mm circle on my printer, (the enclosure limits me a little bit) so that is an 85mm radius... is the Delta radius the printable radius minus the radius of the effector? What would that be for a rostock max v2?

[DeltaCon]

The two have no interaction.
Imagine a marble hanging on a thread. If you swing it in one direction, the projected line on the surface is a straight line. But if you look from aside you can see a path that can be described as a segment of a circle, with the hanging point of the thread as the middle. Radius is the length of the rope. Because of the hotend hanging from above, it makes a similar curve if the deltaradius would not compensate for this effect.

Printable radius you already figured out yourself

[Qdeathstar]

so, how do you figure out what that value is?

[Qdeathstar]

delta radius
looks like it's from where the carriages meet the arms to where the arms meet the effector

[DeltaCon]

Which machine do you have?
Do you have stock arms?
Why do you think the value is off?

If you set your nozzle to Z1 you see a gap between the bed and the nozzle.
Jog the nozzle around in the X and Y plane and play close attention if the gap gets bigger or smaller to the edges of the bed.
If the gap is bigger at the edges you need to raise the value in firmware and vice versa.
Small steps pleas, like 0.05 until you are confident to take bigger ones.

For more accurate calibration you need to get your self comfortable using the paperdrag method, or get some kind of probe.
Earlier I used a digital dial indicator and a mount for it that you can place instead of the hot end. Accurate, but PITA.
Searching this forum will lead to better suggestions.

[DeltaCon]

I am sorry Qdeathstar, I misunderstood your question to be about the horizontal radius...
You found your answer

[Qdeathstar]

i am setting up a wifi duet and isn't a initial value set. i have stock arms, carriages and a 713maker effector.

[Qdeathstar]

what should the horizontal radius normally be?

[Xenocrates]

what should the horizontal radius normally be?

Around 140-144, depending on the carriage set (I have 144.6 as mine in my Duet with the injection molded ones)

[Qdeathstar]

Thanks! I wasn't too far off then... I measured 143.5



If you are familiar with the Duet, do you know if you can change a setting that will let you jog the controls without homing first? I can't home ATM because the steppers are moving down toward the bed, instead of up toward the endstops, and im not sure if that is an issue with stepper direction or if its just that there is a setting in the Duet to tell it where the endstop is (up or down)....

[Xenocrates]

Thanks! I wasn't too far off then... I measured 143.5



If you are familiar with the Duet, do you know if you can change a setting that will let you jog the controls without homing first? I can't home ATM because the steppers are moving down toward the bed, instead of up toward the endstops, and im not sure if that is an issue with stepper direction or if its just that there is a setting in the Duet to tell it where the endstop is (up or down)....

I have always been able to jog at the paneldue without homing. The answer to your issue though, is both. Homedelta is a config file, and I found the stepper directions to be as follows:

Code: Select all

; Axis and motor configuration

M569 P0 S1							; Drive 0 goes forwards

M569 P1 S0							; Drive 1 goes backwards
M569 P2 S1							; Drive 2 goes forwards

M569 P3 S1							; Drive 3 goes forwards

M569 P4 S1							; Drive 4 goes forwards

M574 X2 Y2 Z2 S1					; set endstop configuration (all endstops at high end, active high)

And my homedelta.g is

Code: Select all

; Homing file for RepRapFirmware on Mini Kossel

G91							; use relative positioning

;******* Change F250 in the following line to F2500 when you are finished commissioning

;******* Change 320 in the following to a higher value if your Kossel has taller towers

G1 S1 X600 Y600 Z600 F250	; move all carriages up 600mm, stopping at the endstops

G1 S2 X-3 Y-3 Z-3			; move all carriages down 3mm

G1 S1 X6 Y6 Z6 F250			; move carriages slowly up 6mm, stopping at the endstops

G1 Z-5 F2000				; down a few mm so that we can centre the head

G90							; back to absolute positioning

G1 X0 Y0 F2000				; centre the head and set a reasonable feed rate

[Qdeathstar]

Thanks for the help, Ive got auto cal completing... it is absolutely insane how much the stepper drivers effect the sound of the machine. Now the loudest part is the fans! I can barely hear the motors moving, and i don't even have dampers installed.

Actually, just as i was typing this the head took a nose dive into the bed while completing the last part of the auto cal!?

[Qdeathstar]

Got that issue fixed, looks like... but...

oops
https://www.duet3d.com/forum/thread.php?id=413&p=1
berd air is a no-go directly hooked up to the duet, found out the hard way... worked fine on the Rambo

[Qdeathstar]

...



I have an extra pwm slot that isn't being used atm, and i am wondering how hard it would be to use that as the part fan controller (after getting an ssr)... if it's doable (google is unclear) then i'd feel more comfortable doing that; the mosfet for the fans is smaller than i've soldered before....

do i still need a diode to protect the SSR?

[Xenocrates]

...



I have an extra pwm slot that isn't being used atm, and i am wondering how hard it would be to use that as the part fan controller (after getting an ssr)... if it's doable (google is unclear) then i'd feel more comfortable doing that; the mosfet for the fans is smaller than i've soldered before....

do i still need a diode to protect the SSR?

It's doable using one of the remapping commands (or since you're using an SSR in theory you may be able to use designated fan headers on expansion connector). If you get a good SSR, you shouldn't need a diode. The major issue with the duet's MOSFETs was heat dissipation, which ssr's can handle a lot more than 1w. Many are designed for situations where they might dissipate 50w with a heatsink attached. They are often used to drive motors and heating coils, so the field collapse spiking the voltage shouldn't bother them too much.

[Qdeathstar]

i got this one comming.. it's not a crydon? but i was thinking s center it's just for a fan, it would be ok (since who cares if it fails closed).

https://www.amazon.com/gp/product/B0058 ... UTF8&psc=1

OFC, i do not have much experience with this, so if i am guessing wrong please tell me.


Also, when you do the auto tune on the Duet, does this look right for the G-code to set the PID in the config?

M307 H1 A406.6 C160.8 D15.3 B0 S1 ;PID setting for hot end

Code: Select all

9:39:15 AMM307 H1
Heater 1 model: gain 406.6, time constant 160.8, dead time 15.3, max PWM 1.00, in use: yes, mode: PID
Setpoint change: P4.6, I0.03, D49.4
Load change: P4.6, I0.15, D49.4
9:38:56 AMAuto tune heater 1 with PWM=0.50 completed in 489 sec, maximum temperature reached 227.6C
Use M307 H1 to see the result
9:30:46 AMM303 H1 P0.5 S240
Auto tuning heater 1 - do not leave printer unattended