Answered Missing layers from print and heater problems

well, it could be the heater core or the thermistor... (or anything really)
However all of the electronics (all of them) for the R1/R1+ can be had in a kit for less than $50. From Amazon. Via Prime

The thermistor and heater core are not in the all-in-one kits (unless you include a hotend) but they are cheap.

Specifically we need to know exactly which printer model you have to help point you to the correct hotend parts.

 

That is good enough

The Robo beta, the Robo R1 and the Robo R1+ all look almost identical (they are not).

The R1+ uses a slightly customized version of the RepRap Hexagon hotend.
'Slightly' customized because the thermistor is a specific canister style that only Robo used.
Try these folks for that :

https://www.partsbuilt.com/robo-parts/

(example of the thermsitor: https://www.partsbuilt.com/robo-r1-compatible-thermistor/)

If they are out of stock on an item -- email them and let them know you want it.


For the kits (all the other electronics) you can find an assortment of those on Amazon -- here are some examples (not recommendations -- just examples):

https://smile.amazon.com/Aokin-Printer-Controller-Arduino-Heatsink/dp/B07Q5R6YSK/

https://smile.amazon.com/Eiechip-CNC-3D-Printer-Kit/dp/B07BKVPZ71

https://smile.amazon.com/Quimat-Printer-Controller-Arduino-Upgraded/dp/B06XS8G1BB

Quality-wise they will all likely be the same.



Bear in mind that with the R1+ if you need to swap the RAMPS 1.4 card you need to look at this thread:

http://community.robo3d.com/index.p...and-rewiring-to-make-generic-ramps-work.8356/

 

Worst case you CAN replace the hotend with something like an E3D which is a better hotend than the hexagon, but that will cost more than the thermistor for the hexagon and also more than the entire hexagon hotend... BUT it has wide availability of spare parts so you are not stuck waiting. There is a thread for how to do the upgrade to the E3D from the hexagon as well.