3DTouch deploys too soon after probe

Hi!

My 3DTouch(BLtouch clone) has the following issue:
*3Dtouch deploys
*Z-axis moves down
*The tip of 3DTouch touches the buildplate
*The tip retracts
*Z-axis starts moving up
*3Dtouch deploys for 2nd probing too soon, hitting the buildplate on retract

Is there somewhere in Marlin I can add more delay before the 2nd deployment of the probe?

[marlinfw.org]

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Kind regards
Imqqmi

NFAN CoreXY printer:
[reprap.org]

M400 you say..

How would I go about writing this? Guess this should be in the start Gcode then? But all I do probing wise is a G28. I dont think I can put an M400 inside this G28 can I?

You can use G28 to level once and G29 do level the whole bed with auto bed leveling. Since you have a 3Dtouch I suggest you use G29 but you need to set up the perimeters in Marlin. Anyway, you can put the M400 after the G28 so that it first finished the moves of G28 before doing the next thing basically.

So:
G28
M400

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http://www.marinusdebeer.nl/

It is between the moves inside the G28/G29 I have the problem. Putting a M400 outside of these didnt make it better. Thanks anyway

It's only possible to change the behaviour of the G28 and G29 homing and levelling routines by changing the source code. I did something like that with a servo probe that retracted before the z axis lifted up a bit, making the probe bump into the bed. My change was for an older version on marlin though, and I've scrapped the i3 clone 3D printer and build a corexy that doesn't need levelling (using duet 2 wifi, so no marlin anymore).

It shouldn't be hard to do a M400 like instruction in the source code if you know your way around C code. If that's not an option you could do a feature request on the marlin github page. Maybe someone else has done a mod you may be able to integrate into your version.

I just had a look at the configuration.h file, there's a bltouch specific setting:

#define BLTOUCH_DELAY 375

Did you try this? I'm not sure what it does exactly but might be worth a shot. The code should look like this:

#define BLTOUCH
#if ENABLED(BLTOUCH)
  #define BLTOUCH_DELAY 375   // (ms) Enable and increase if needed
#endif

There's also this:

#define Z_CLEARANCE_DEPLOY_PROBE   10 // Z Clearance for Deploy/Stow
#define Z_CLEARANCE_BETWEEN_PROBES  5 // Z Clearance between probe points
#define Z_CLEARANCE_MULTI_PROBE     5 // Z Clearance between multiple probes

Did you try increasing the clearance?

---

--
Kind regards
Imqqmi

NFAN CoreXY printer:
[reprap.org]