z-stop don't work immediately

I've a random problem with my zortrax m200.

Is it a problem ? Is not a problem ?

Since i don’t know and so i ask.

Problem is that sometime, random, the plate do not stop immediately when it touch the nozzle.

Some time i can see the spring a little compress because z-axis do not stop immediately but this ONLY in the center because for example in the home position the plate stop immediately every time.

So what happen ? Happen that in the center of my plate i've some "little" funnel caused by nozzle.

Some week ago i try to apply this fix: http://forum.zortrax.com/index.php?/topic/2371-auto-calibration-failed-noozle-crash-into-plate/#entry26702

with a wire from the hotend to the extruder but no change for me.

So the question is ... it's normal or not ?

Either nozzle is dirty or perforated plate could have been damaged. 

How i can check if the plate (700 hours of work) is damaged ?

How i can check if the plate (700 hours of work) is damaged ?

You can look at connector and platform itself, if it looks similar to my photos - its most likely it but after 700 hours of printing, its 99,99% probability thats Platform fault and it requires replacing.

You can look at connector and platform itself, if it looks similar to my photos - its most likely it but after 700 hours of printing, its 99,99% probability thats Platform fault and it requires replacing.

By looking at those pictures it seems the build plate was not leveled properly! ;D

I find that a sharpened spatula will extend the life of the build plate because it is less likely to take a chunk out of the surface when less pressure needs to be applied. I would also be inclined to say "get a new perforated plate" after 700 hours of printing!

700 hours and change the plate? I have had 2-3 plates changed due to warranty reasons and they still look nice, not abused like in the pics above. My plates have 7000 printing hours on them. No metal is showing and no white paint has come off either.

Marcin my plate is not like your :)

It's like new,

Here u can see the z-stop "hard":

https://www.youtube.com/watch?v=1_rETC63eO0&feature=youtu.be

place a small square piece of aluminum foil into the place where the nozle is touching the perf board just only for calibration and remove it before the print. It seems that your perf board is damaged from a nozzle impact in that place and has a bad contact with the nozzle.

Believe me guys, I've seen Perforated plates in much worse condition (<100 hours) but your plate looks nice, it has been treated well. If you are sure that wasn't dirty nozzle and small connector is not broken, I would go for replacing plate in first place. If that wont help however, you can reach us through Support Form, so we can find suitable solution (http://support.zortrax.com/support-form/). 

The key here is not "My plate has stood up to x000 hours of printing without breaking" the issue is not all plates are like the few displayed here. Some plates will stand up to a beating and last for a long time and some will just be defective out of the box and only show issues after 20 hours of printing or more.

Just because I run 4 M200's and only 3 of them have never had a perforated board replacement does not mean the fourth will be the same. Unfortunately not all plates are created with the same standard.

-NS

Well here is my take on it.. The printer uses conductivity to determine zero.. You have a really nice insulator hanging from the nozzle right before impact. I generally remove that small piece of filament with the tweezers right before contact with the plate. I also use a brass brush to keep nozzle and center square clean. Just a thought..

Actual i've fixed the problem with a third part nozzle that have a major contact face with the plate.

The top of the nozzle is not rounded, it's flat.

Tested for 9 print work until now, 0 problem with the z-stop.

My problem is that in the plate there's a little zone broken from two hole and the standard nozzle have a bad contact in that zone.

Since i don't know why is broken in that zone, when i discovered the problem immediately i put (one month ago) a cable from the hotend to the extruder but i think it was too late.

I'm planning to build with the late my own nozzle similar that in the photos but with a biggest flat surface to increase contact area and avoid other hole in my plate.

As Kyle, mentioned I always grab the pre extruded filament that comes out and try to brush or remove right before the print.  It's not a huge problem if you don't obviously but it's definitely a barrier for that initial electrical contact.

Curious if you ever have print issues. with a wide flat nozzle end.  Keep us posted.  I would image this has to have some draft angle built in as you don't want the head to start peeling up already printed filament layers while printing.