Z endstop at high end should set Z position to maximum

thomas_rudloff

Deleting the malicious line from homez.g and homeall.g does the trick. DC42 mentioned somewhere that the firmware sets the value correct upon hitting the end stop. So no need to mess it up.

The PT1000 does not work on the bed thermistor input either. It tells a short when connected and an open circuit when disconnected. I measure a slightly different voltage. Does someone save a few Cents by not using 0.1% resistors or does the CPU have such a bad reference voltage?

Phaedrux

@thomas_rudloff said in Z endstop at high end should set Z position to maximum:

Deleting the malicious line from homez.g and homeall.g does the trick.

What did you delete from the homing files?
Did you correct the z axis minima and maxima?

Phaedrux

Is this on a meastro or wifi board?

thomas_rudloff

Oh sorry, I need some practice on reporting here. It is a Maestro board. Now with the latest release software. Just for completeness.

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool v2 on Mon Jul 29 2019 18:46:55 GMT+0200 (Central European Summer Time)
G91 ; relative positioning
G1 Z5 F6000 S2 ; lift Z relative to current position
G1 S1 Z165 F1800 ; move Z up until the endstop is triggered
;G92 Z0 ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
;G91 ; relative positioning
;G1 S2 Z5 F100 ; lift Z relative to current position
;G90 ; absolute positioning

I set back the range to positive values from zero like it was before I started trying different configuration.

I have the three Z stepper on three external TB6600 (modified the opto-coupler of this garbage to make it work) and a 74HC245 as driver (the only suitable chip conrad had in stock) together with a fancy circuitry for synchronization at the Z stop I developed. But this was a mistake either. The board can do this better. I read today. So I will change this to the internal drive and use a TB6600 for the extruder. Or better the add on board. We will see. I hope I will find the article about Z axis synchronization with Z probing again. It looked like it was made for me.

en_passant

@thomas_rudloff said in Z endstop at high end should set Z position to maximum:

Thanks,

I thought of problems of the RC either and will try the release today. Last time I looked, this seemed to be the latest version. The problem is, that this is too complex to know everything at the beginning. I can do root cause analysis on aircraft electronic failures, but I am an absolute beginner on Duett. So please guide me.

Concerning the Z Axis settings: This was my latest setup. It has the advantage of setting the Z value to zero manually. The config tool does not set to maximum in any configuration I tried. Is the source code available? I will fix it myself if no one does.

It is to early to tweak the config files by hand. I still have to do some improvements on the hardware.

Just picked this one up as it sounds similar to the issue I was having (feel free to look at my numerous posts vis a vis upgrading my board/ firmware/ gcode #basically-a-new-printer) and really must say... oh. my. god.

Between the wikis and the forums, this place is an absolute treasure trove of information! The folks here have cultivated/ created/ generated one of the best open-source resources (personally) I've ever seen. The participation from people a) willing to help and b) able to help is outstanding; without having to wait 3 weeks for the 1 guy who doesn't have his arse facing the sky to send a semi-helpful reply.

remember this is open-source and has multiple applications and many many many more methods of doing so;
remember you're free to chose another platform (if you're struggling with duet, go have fun with octoprint...);
ask nicely and show some humility - coming here (where resides some clever folks from my observations) throwing the bosses weekly buzzwords like RCA isn't going to win you any favours and either is banging the drum about aircraft electronics like it's going to impress anyone

... fortunately, the people with the noodles are so nice they continue to help regardless

e_p
just-another-newcomer-seeking-help, CEng RAeS [... Avionics, hehe ]

Phaedrux

@thomas_rudloff said in Z endstop at high end should set Z position to maximum:

M305 P0 X503 R ; Configure PT1000 for heater 0

I think your PT1000 config line is missing some parameters.

https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors

thomas_rudloff

Oh, now I see it thanks. I chose the PT1000 because, if I understood right what I read, are supported without adapter and was able to buy some at Conrad on a Saturday. Meanwhile I ordered a thermocouple adapter board, that is, hopefully, on the way today. I have K-types at home. Now I recall that printers usually use 100k NTC for the bed. Is this the NTC the way to go for best serviceability? Precission is not that much an issue on my opinion, because you need to tweak to filament and bed anyway.

A Former User

@thomas_rudloff said in Z endstop at high end should set Z position to maximum:

Oh, now I see it thanks. I chose the PT1000 because, if I understood right what I read, are supported without adapter and was able to buy some at Conrad on a Saturday. Meanwhile I ordered a thermocouple adapter board, that is, hopefully, on the way today. I have K-types at home. Now I recall that printers usually use 100k NTC for the bed. Is this the NTC the way to go for best serviceability? Precission is not that much an issue on my opinion, because you need to tweak to filament and bed anyway.

NTC and PT1000 are both supported without adapters. Thermocouple and PT100 adapter boards are available. Its mainly a question of accuracy, operating temperature and cost, pick two type of deal.

Oh sorry, I need some practice on reporting here

You'll find most of this applicable to the internet and life in general as well; https://forum.duet3d.com/topic/5909/guide-for-posting-requests-for-help

nophead

@thomas_rudloff NTCs are fine for beds. I use 1% Epcos B57861S104F40 epoxy bead thermistors that come with PTFE covered leads. I attach them with JB-Weld.

At typical bed temperatures 1% is only a degree or so so I don't see any point in being more accurate. It would be a good bed that has less temperature difference across its surface.

thomas_rudloff

Thanks to all

Just deleting the R does the trick. I read somewhere that on newer boards the defaults are OK.