Well first i tried a PEI surface on a glas bed and black alunminium beneath. Big surprise it didn´t work. The deviations were extreme. The map looked like a landscape with a lot of mountains. Then i managed to get some PEI without the glue sheet preinstalled. As adviced i use a oven coating on it and placed it for two hours 170° in my domestic oven.

First impression after the installation. I´ve never expected that level of accuracy. I don´t remember the values but they were amazing and the repeatability...

But i had to use a little force to get some printings of the PEI. Doing so caused the coating to be partially seperated from the PEI. Luckily i use 3 Point Leveling to correct the tilt and the places where the sensor measures are still intact. But i´m afraid sooner or later the PEI will be unuseable for the Mini IR again...

I thought i share my experiences and ask for suggestions. Are PEI and the Mini IR a impasse?

David Crocker's Solutions blog

Scroll down to Bed Surface and there it is in the last paragraph. But it is necessary to have a PEI Sheet without glue on it and a seperate adhesive sheet like the 3M 468MP. But as i already stated i´m not satisfied with the result yet. Maybe the coating didn´t "connect" to the PEI sufficiently... Might depend on the used spray. I can´t find the one i used but this one seems similar BBQ and Stove Paint

Perhaps try a longer or higher temperature in the oven. I don´t know how far you can go though.

Well first i tried a PEI surface on a glas bed and black alunminium beneath. Big surprise it didn´t work. The deviations were extreme. The map looked like a landscape with a lot of mountains. Then i managed to get some PEI without the glue sheet preinstalled. As adviced i use a oven coating on it and placed it for two hours 170° in my domestic oven.

First impression after the installation. I´ve never expected that level of accuracy. I don´t remember the values but they were amazing and the repeatability...

But i had to use a little force to get some printings of the PEI. Doing so caused the coating to be partially seperated from the PEI. Luckily i use 3 Point Leveling to correct the tilt and the places where the sensor measures are still intact. But i´m afraid sooner or later the PEI will be unuseable for the Mini IR again...

I thought i share my experiences and ask for suggestions. Are PEI and the Mini IR a impasse?

Thanks for all the answers. I´m convinced. Especially seeing that there is developement and dedication is reassuring. I´m looking forward to see the filament sensors emerge. And sorry the point about the Bed Leveling... i´ve obviously overlooked that or simply searched with the wrong words...

Concerning the feed sensors: Will it be possible to use them to calibrate the extrusion speed? e.g. running an extrusion and comparing the intented steps/distances with the measurements so you can finetune the maximum extrusion speed?

I´m currently evaluating two different electronics and firmwares for my next printer a CoreXY machine. I´m not sure though if there is a eletronic/firmware fullfill all my wishes. Maybe someone has some experience on it.

1. MABL A "motorised auto bed leveling" (https://www.youtube.com/watch?v=76bUTPKNloM) supported by a combination of DUE + RADDS and the repetier firmware with a height sensor and three z axis motors. Can the same be done on a Duet? Does the Duet support repetier?

2. Filament feed sensor like the FTS by Sparklab. It uses two wheels, a Hall-E-Endstop and a magnet to measure the movement of the filament and compare it to the steps of the extruder. Thus it is capable of detecting runouts, jams and even to slow down the print. Theoretically it could even be used to autocalibrate new filament. But at least the aforementioned options are already supported by repetier. Can RepRapFirmware and duet do the same?

3. PT100 simply an option i´d like to have but requires soldering and tinkering with the RADDS solution. One of the reasons i´d prefer the duet as is seems to me a better out of the box solution. Clean and easy. Also the ease of use and configuring seems to be intriguing. I´m not sure if RADDS/repetier can compete there.

Thanks.