Brand new prusa mini: Z needs to adjust on every new print.  

RE: Brand new prusa mini: Z needs to adjust on every new print.

Because it makes not sense from practical print of view but from price/sales point of view it makes and that's why it's a super-duper special feature 🙂

RE: Brand new prusa mini: Z needs to adjust on every new print.

Posted by: @simon-10

[...] Sorry thats bullshit!

You get what was on the label on the box on the day you paid for it. If something is truly defective, definitely work with support to get it fixed or replaced under warranty. Otherwise, buying a product does not entitle you to life-long free hardware upgrades. This is very similar to the process that we went through with the original Mk3 PINDAv1 probes.

Definitely avoid buying a car. I've paid a hell of a lot more for a car that had well-known issues that were fixed in subsequent years but never addressed on mine. New products with improvements come out all the time. At least Prusa is providing a relatively inexpensive upgrade path for those who feel they "must" have it.

RE: Brand new prusa mini: Z needs to adjust on every new print.

@bobstro

This is not life-free hardware upgrades, this is a design that was launched too early because they wanted to take advantage of the generated hype and that it's defective and does not work as advertised. This is like shipping a mobile phone with a defective battery or a laptop with a keyboard that breaks easily, it's not consumers fault to buy them.

RE: Brand new prusa mini: Z needs to adjust on every new print.

The problem here I think the Mini as it was is somewhere in the middle between defective and underperforming.

For the people where 9 out of 10 prints worked, it's fair to say that increasing reliability is a feature upgrade for which it's fair to charge money. In this case I don't think that there are false promises made about what the printer can do, only that the quality is not as good as hoped for, but the problem with all products in general is that you can often only try to judge the quality by the reputation of the company or the price and people have high expectations of Prusa, but on the other hand it is clear that you can expect less for half the price of the MK3. In this case it is more a problem of what kind of expectations are raised and fulfilled.

For people where 9 out of 10 prints fail because the sensor is so inaccurate that the first layers become more inconsistent as if you just leave the bed as it is without the sensor you can assume that the printer is defective and not suitable for the purpose it was sold for. In this case it is clear that there is a defect where the manufacturer even has the duty to remove it.

Which of the cases now rather applies is a question how well or badly the sensor functions with each individual printer.

RE: Brand new prusa mini: Z needs to adjust on every new print.

I had previously contacted prusa before about the Z issue, and just sent them another email about it. They're sending me the new SuperPINDA as an RMA for the MINDA free of charge. They said it should be dispatched today, so if they're sending them out, MAYBE the new firmware is almost ready. 

RE: Brand new prusa mini: Z needs to adjust on every new print.

I just tried to get them to replace mine no luck I will just keep doing my 5 min warm up it has helped out a lot but still not perfect 

RE: Brand new prusa mini: Z needs to adjust on every new print.

Posted by: @danielo

 

This is not life-free hardware upgrades, this is a design that was launched too early because they wanted to take advantage of the generated hype and that it's defective and does not work as advertised.

Some -- and certainly not all -- users are having problems.

• Many people are quite happy with the Mini as an inexpensive printer as-is. A look at the non-support forums shows many people raving about the printer and its results. A design defect would affect all users.
• A relatively small number have received defective MINDA probes and Prusa has replaced them. That is a defective part, not a design defect.
• Some people are being told that they need to have realistic expectations for a low-cost printer. They may have to adjust startup times and just aren't happy about it, even if there are reasonable workarounds and firmware upgrades that fix the problem. The Mini was not sold originally as having a temperature-compensated leveling mechanism. One is available as an upgrade now. Paying for upgrades is normal.

It's awesome that Prusa is replacing probes free of charge in many cases. I can understand why they're not providing an upgraded part for free for every Mini ever sold. If somebody paid for and received a Mini that is functional but they just feel entitled to a free upgrade, Prusa is under no obligation to provide free hardware upgrades. If they do, it's an example of their excellent customer service.

This is like shipping a mobile phone with a defective battery or a laptop with a keyboard that breaks easily, it's not consumers fault to buy them.

If the battery is truly defective, yes. If the owner is simply expecting it to perform the same as the battery on their higher-end phone, no. In any case, an odd defective battery is not a design defect affecting every user. A defective battery should be replaced. That doesn't mean every customer that purchased a functional phone with a basic battery is entitled to an upgraded battery when a new model is released.

RE: Brand new prusa mini: Z needs to adjust on every new print.

@skreelink

Apparently the SuperPINDA will work with the current firmware, which I admit surprised me, but as they are already shipping the Mini+ it must be functional!

RE: Brand new prusa mini: Z needs to adjust on every new print.

Posted by: @gordon-w

@skreelink

Apparently the SuperPINDA will work with the current firmware, which I admit surprised me, but as they are already shipping the Mini+ it must be functional!

Actually, that makes sense... They did say it does not have a thermistor, and instead the probe itself is temperature-independent. Thus, it shouldn't need any changes to the firmware. They just had to update the MK3S firmware to not look for thermistor values, which in the Mini, never had. It should just act like the regular MINDA, just without the temperature drift.

RE: Brand new prusa mini: Z needs to adjust on every new print.

The Mini was not sold originally as having a temperature-compensated leveling mechanism. One is available as an upgrade now. Paying for upgrades is normal

No, it was sold as a farm-ready workhouse 3D-printer. Having to cooldown between prints, warm it up for 3 or 5 minutes and babysit every first layer is not what I would choose for a printing farm.

Many of the users may be printing once a day, or even once a month, that's why they are not having any of those problems.

I didn't had them at first either, it was when I tried to squeeze it a bit more when they appeared. In any case, I'm more than happy to pay for an upgrade that will make my mini the printer it was advertised.

RE: Brand new prusa mini: Z needs to adjust on every new print.

Just updating you guys, my SPINDA came in today, got it all installed aaaand wow. It's apparently more sensitive and reads much further away. My original Z- for my smooth sheet was -0.920, after correctly installing the SPINDA 3 times using the tip of a ziptie (calipers measure it to be 0.9mm) my Z- was all the way down to -1.800! Almost a full mm difference. This of course, would not do, as my textured sheet needs about 0.25-0.3mm play since it's thinner, the max Z- is -2.000. I ended up using the middle of the ziptie to give myself leeway and now my Z offsets are -1.500 PEI and -1.800 TXT. Works for me, easy to remember until the sheet save feature appears in the firmware.

So my suggestion to anyone who gets one: Use the thicker part of the ziptie or something up to ~1.5mm thick to get the SPINDA high enough to Z adjust correctly. I guess the solution to heat creep in the probe was to just make it work further away.

RE: Brand new prusa mini: Z needs to adjust on every new print.

@skreelink

Thanks for the feedback. I think that the sensor has a higher switching distance of about 2-4mm.

RE: Brand new prusa mini: Z needs to adjust on every new print.

I'm definitely having issues with this. Normally I run Z-axis calibration by printing a large single layer octagon and typically I print a few of those back to back in order to pick the right Z offset. Doing several prints back to back means that all the printing parts get up to temp and stay nice and warm, so when I'm printing the last final octagon to confirm the Z offset, the PINDA probe is also nice and toasty. The problem with this is that next time I run a print, with the printer starting from cold, the first layer is typically printed too high and you can see this by looking at the bottom of the printed model. If you print the same model for the second or third time, things warm up and the first layer goes back to looking normal.

This is why, as per suggestions above, on startup I typically lower the whole carriage so it sits just above the platform and hit Preheat. I leave that for 5-10min and then proceed with normal printing. It's an annoying workaround and definitely something I'd class as a flaw of the printer.

RE: Brand new prusa mini: Z needs to adjust on every new print.

I want to chime in here that getting a SuperPINDA completely fixed the issues which I had with my printer. It is reliable and works well now. I'm slightly irked I had to pay to replace a completely inadequate sensor with a functional one after months of troubleshooting, workarounds, ruined nozzles and scored steel plates, etc. But I have to admit that with the new sensor, the MINI (and by extension the MINI+) are everything originally advertised and work exceptionally well for the price point and size.

If you're still coming here via search engines, trying to fix your MINI, and your sensor is orange? Buy the replacement and install it. Your printer will become many orders of magnitude more reliable.

RE: Brand new prusa mini: Z needs to adjust on every new print.

Well I had similar issues on my mini delivered in early November.  The first print of the day (from cold startup) would always fail the first layer, and upon close inspection, was visibly printing higher than the calibration done prior.  Reprint would usually be successful. It seems that's because the MINDA was triggering at a different distance when only slightly warmer after the first attempted print.  I got on chat support and the tech seemed to need proof.  I ended up making a youtube video (while on chat) of an attempted print from fully cooled off and one just after that failed print where the first layer was clearly different.  I had to show that the offset was the same on both.  This seemed to satisfy and so he had a superPINDA mailed my way.  I gotta say if I wasn't an experienced user with a readily available means of making a quick youtube video, this would have been virtually impossible to have pulled off during a live chat.  It took over an hour and some quick mobile to youtube with pointing out the differences and providing time stamps.  I'm grateful that they're sending me a superPINDA but at the same time they initially provided me with a sensor that has sucked up quite a bit of wasted time troubleshooting.  Do all MINDAs suck?  Or are some like mine more sensitive than others and I got unlucky?  I'm guessing it's the latter as every first cold print failing would really frustrate beginners.  I'm glad they've sorted it out with this new sensor.  However, I think the moment someone reports an issue with the original MINDA, they should just send out the new part with no fuss.  My 2 cents.

RE: Brand new prusa mini: Z needs to adjust on every new print.

I installed my SuperPINDA a few days ago and haven't had to change the Z since. I've done at least a dozen prints since then. I used to change the Z before every print.

RE: Brand new prusa mini: Z needs to adjust on every new print.

Hi,

I received the new SuperPinda for free from Prusa Support. Its working great now. 
No issues with Z high. Everything is very reliable.