Done with my MK2.5 😉  

Re: Done with my MK2.5 😉

Nice, looks like you are happy. I expect mine to come any minute now.

Re: Done with my MK2.5 😉

as long as it works 🙂 test print looks ok.

Re: Done with my MK2.5 😉

Although I will probably receive my order sometime in April, I've already printed the parts in PETG and ABS. That removable bed plate looks sweet, probably the most important bit of the upgrade for me 😀 . Have you tried different materials? Does the PINDA probe adjust for the temperature difference?

Re: Done with my MK2.5 😉

I agree, for me the magnetic heatbed was the main reason to upgrade, as well. But also the Noctua fan is worth it although you could just upgrade the existing mk2(s) extruder with a one of these. BTW - the accidental cooling of the heatbed due the small side fan, seems to be almost fixed by the new fan.

I didn't try other then PLA yet. Also i have had no chance to challenge the PINDA probe with high bed temperatures yet, but at least the PINDA temp is now showing up in the support section of the firmware.

Best,
Marko

Re: Done with my MK2.5 😉

Can you help me out in terms of printing the parts. I have been trying all day to print them out. I separated the stls so there is less chance of failure and twice Ive had the error "Bed thermal runaway". Ive successfully done about a third of the parts mainly the small ones. But no such luck with the larger ones. Im beginning to hate PET. Any help would be appreciated.

Re: Done with my MK2.5 😉

I have my upgrade kit and had a few questions if you have the time!...

- Does the PETG provided leave any extra left over after printing the parts? (I had issues with my extruder so already had taken the Prusa apart and was trying to print the parts with my other printer. The problem is I havent printed with PETG on the other printer so messed up the first layer, Just wondering how many more layers I have to potentially mess up before I dont have enough for the parts.)
- Can I get away with still using the current Rambo cover and just print the extruder parts. I would rather print the Rambo cover with the Prusa as its better quality and more reliable.
- Anything else you wish you knew now that you have it all built?

Re: Done with my MK2.5 😉

Ive been having tons of failures and there appears to still be enough on the spool to finish the prints.

Re: Done with my MK2.5 😉

According to Octoprint's filament manager, I have 49g/200g of the provided PETG left over. I printed all the parts with 2 perimeters, 3 bottom, 3 top layers, 30% infill.

You might be able to get away with using the old Rambo case, but your heatbed cables might not be as secure using the new wrap they have.

The only thing I'd have done differently with the build would be to put together the bondtech idler before dismantling the Mk2S. One of the holes for the pulley shaft cracked when I tried to force it in. I was able to fix it with some glue and didn't have any problems printing a new one since there's no force pulling on it.

Re: Done with my MK2.5 😉

Can you help me with my issue?

Re: Done with my MK2.5 😉

@john.s31

Check underneath your bed to make sure the thermistor hasn't pulled out of the tape. You get a bed thermal runaway error when the firmware is sending power to the heated bed and not seeing an increase in temperature. If the thermistor is loose it could explain why the small parts will finish (bed isn't moving as far) and the larger parts won't.

How far into the large prints do you get? Do you notice the temperature dropping and staying below where it should be?

Re: Done with my MK2.5 😉

The only thing I'd have done differently with the build would be to put together the bondtech idler before dismantling the Mk2S. One of the holes for the pulley shaft cracked when I tried to force it in. I was able to fix it with some glue and didn't have any problems printing a new one since there's no force pulling on it.

I had the same issue with mine cracking as well, but for me it was intact enough to work long enough to print a new one without any glue. On the second print the trick I used was to use the 3.1mm drill bit from my MK2->MK2S part of the upgrade to clean up the holes a bit prior to pushing the pulley shaft in.

Re: Done with my MK2.5 😉

@john.s3
Try to place the part on the left side of the heat bed, far from the center as the thermistor in the center might get to much cooling from the fans. The side fan on the MK2(S) will cool the heat bed additionally so you might want to direct the air flow away from the heat bed by taping a piece of paper on the bottom of that fan.

@vladimir.h3
1. There is enough PETG on the roll to have dozens of first layer failures. If you can't fix the first layer problem with the PEI sheet try a layer of glue stick, this might help here.

2. The old Rambo cover should work. Only the hole for the heat bed cable might be too big on the old one.

3. Like @Zinga & @joe.h mentioned, the 3d printed pulley shaft for the Bondtech extruder gear is too small. Try to widen it until it fits without breaking the piece.
Additionally, take care of the extruder cables when tying them together as described in the assembly instructions. In my case they prevented the x-carriage to reach the end-stop switch because the cable bundle was too thick and touched the frame first.

Re: Done with my MK2.5 😉

Can you help me out in terms of printing the parts. I have been trying all day to print them out. I separated the stls so there is less chance of failure and twice Ive had the error "Bed thermal runaway". Ive successfully done about a third of the parts mainly the small ones. But no such luck with the larger ones. Im beginning to hate PET. Any help would be appreciated.

Try printing the parts to one side of the bed rather than in the centre. When the print head is constantly around the middle of the bed which is where the thermister is the cooling fan can cool the bed down and trigger a runaway.

Re: Done with my MK2.5 😉

That print bed is simply gorgeous. So jealous...

Re: Done with my MK2.5 😉

Has you printed directly the gcode files or you has worked with the STL files in Slic3r or other program?

Re: Done with my MK2.5 😉

@manuel.t2 Yes, I have printed both the gcodes for extruder and Rambo case provided by Prusa3d. It saves a lot of time but you really need to take care for the first layer. I believe, directing the air flow of the side fan away from the print bed with a small piece of paper will improve the bed adhesion tremendously.

Re: Done with my MK2.5 😉

Meanwhile, i finished my custom MK3 style y front plate. It's made of PETG. What do you think?

Re: Done with my MK2.5 😉

Speaking of thermal runaway, I now see a ton of it with the new extruder / fan vent at the hotend side when using PLA. Always caused when the print cooling fan comes on. I have to lower max fan speed from 100% to like 40% for it to not happen. Anyone else seeing this or just me?

Re: Done with my MK2.5 😉

Meanwhile, i finished my custom MK3 style y front plate. It's made of PETG. What do you think?

just need some external TMC steppers now. 🙂

is it 100% infill? looks thick enough but i still rather alu/steel. however i guess this might be better than the threaded screw for the belt, i am sure that screw bends under tension. there is also the Bear mod that adds extrusion for it and template to drill holes in the frame to attach like MK3.