MK3S to MK3S+ upgrade kit  

RE: MK3S to MK3S+ upgrade kit

Can someone explain the graphs?  I am not sure what they are showing.  

RE: MK3S to MK3S+ upgrade kit

@tim-2

Making a guess at the data.  5 sensors are used and no increase in deviation up to  from 0 -100 degrees C. (Another words freezing at 32 degrees F to Boiling 212 degrees F)  Does this sound right?  I would love to see a magnetic spectrograph of an object on a bed plate how the sensor sees each magnet.

RE: MK3S to MK3S+ upgrade kit

@matt-2

Hi Matt, I believe that the Mk2, Mk2S and Mini, had 3 wire Pinda/Minda sensors, the Mk3/Mk3S had 4 wire Pinda with Thermistor, and the Mk3S+ and Mini+  have reverted to the three wire pinda with better temperature stability.

regards Joan

RE: MK3S to MK3S+ upgrade kit

@joantabb

Very interesting.  You would think the heat sensor would help and not hurt sensitivity.  

RE: MK3S to MK3S+ upgrade kit

@david-10

My guess at the plots is they show five sensors of a type (the new SPINDA) and their respective trigger points as they are heated.  The two plots are RANGE and HYSTERESIS.

Range is the initial trigger point.  So when Prusa is moving the extruder down to the sense point, the plot of the left is key.

Hysteresis is the "backlash" the sensors have. When Prusa moves the extruder up for a resample, how far up does the extruder need to move before the sensor 'undetects' the surface.  Between the two, the info tells Prusa how far they need to move the extruder up and down to take several altitude readings. And, the data also says not to use the upwards undetect point for anything useful. 

More info on Hysteresis: https://en.wikipedia.org/wiki/Hysteresis

RE: MK3S to MK3S+ upgrade kit

@david-10

As for field sensitivity - Omron has a good tech sheet somewhere on their site that describes the sensitivity pattern for shielded and unshielded inductive proximity detectors. Worth reading if you are an information hound like me.

RE: MK3S to MK3S+ upgrade kit

@joantabb

Yes, that's right. Having upgraded the v1 PINDA from my MINI, and the v2 PINDA from my MK3S, I can confirm that the v2 sensor added a fourth wire to allow for a thermistor output, and the v3 (Super)PINDA went back to three presumably as the performance was now so consistent that it wasn't worth the extra money to keep the thermistor in there.

Also, I note that the v1 PINDA has a yellow tip, the v2 tip is grey, and the v3 is black. This is from my statistically insignificant sample size of four PINDAs that may be down to pure chance rather than be a reliable fact.

RE: MK3S to MK3S+ upgrade kit

@matt-2

Fascinating stuff on the Pinda.  Hopefully, this perfects the standard.  

RE: MK3S to MK3S+ upgrade kit

@tim-2

The graphs do not exactly show the precision you would want.  Then again, maybe I am too demanding.  

RE: MK3S to MK3S+ upgrade kit

@cwbullet

Sure they do.  The latest SPINDA is doing a wonderful job.  

I think what you are confusing is accuracy versus repeatability. The plots say nothing about repeatability. 

Sure, each printer needs to be calibrated to the SPINDA installed: so there is the need to further calibrate the accuracy using Z-offset.  Once calibrated, the repeatability is very very good.

RE: MK3S to MK3S+ upgrade kit

@matt-2

I think if you shop around you can buy the SPINDA version in a variety of colors .. black, grey, white... lol. Or, be creative, make a ring in whatever color you want. Though, I might avoid metal filled polymers for my ring. lol.

RE: MK3S to MK3S+ upgrade kit

@tim-2

Do you have any links?

RE: MK3S to MK3S+ upgrade kit

@cwbullet

No - but eventually I will find the part Prusa is using so I won't have to pay $50USD for shipping a $20 part. Or I'll find an Omron sensor to fit.

RE: MK3S to MK3S+ upgrade kit

@tim-2

I hope you are right.  The shortages are killing hobbyists.  

RE: MK3S to MK3S+ upgrade kit

I'm putting the Super PINDA through its paces.  I've recently discovered PRUSA's PC (polycarbonate) 265-285 degrees C Bed 100-120 degrees C.  This makes pretty good gear bearings also known as planetary gears.  I was expecting a thermal drift from the sensor and I have not after hours of printing. After 6 bearings x 3.5 hours and 1 Han Solo (in-cased in carbonite for all the Starwars fans) .  I'm impressed!

RE: MK3S to MK3S+ upgrade kit

Prusa is noticeably silent and they missed the April dates for product availability and Prusa Control.  

RE: MK3S to MK3S+ upgrade kit

@cwbullet

In the latest Prusa Live webcast they mentioned the component shortage and from their comments it's quite obvious that it is severely impacting their product plans and timelines.

RE: MK3S to MK3S+ upgrade kit

@cwbullet and @Tim: spinda is

labelled: Pepperl + Fuchs NBN 2,5-8GM35-E1-Y

RE: MK3S to MK3S+ upgrade kit

@fuchsr

Thanks.  I wonder what is impacting Prusa Control?

RE: MK3S to MK3S+ upgrade kit

Don't know. Frankly, with my former CIO hat on, I wonder why they even bother. Given pretty decent alternatives such as Octoprint, Astroprint , etc, you have to come up with some extraordinary features to justify putting precious developer resources on it. I'd put my emphasis on print farm management but then again how many of their customers actually run a print farm?