After a few hickups I finished building my MK4 kit and Tukkari enclosure. The first few prints have been fantastic.
My MK4 kit had a couple bad bearings, so I replaced all the bearings and rods on the X and Y axes with MISUMI equivalents. I noticed that they have a fair bit less slop in the movement and are overall quieter.
I also made a custom G10+steel print sheet, and it's working exceptionally well with PETG. It sticks strongly while hot, and doesn't release until the bed drops below about 40 deg C at which point parts pop off easily. It leaves a super gloss surface on the first layer as well. If anyone is interested in building one, here are the parts I used:
(253.8x241mm steel sheet) https://www.aliexpress.us/item/2251832760691866.html
(white 250x240x1mm g10 sheet) https://www.aliexpress.us/item/2255801004367032.html
I bonded them together with 3M 200MP double-stick tape (which is thin, strong, and heat-resistant) and filed notches in the g10 to match the sheet. I didn't abrade the G10, PETG sticks perfectly while glossy. I was very careful about cleaning it with iso. alcohol before printing, and I wipe it again every print or two.
The filament dryer is a Sunlu S1 Plus, which has a built-in fan to circulate air for better drying. I printed this guide and used a PC4-M10 fitting and 4mm OD teflon tube with it to reduce friction into the enclosure:
https://www.thingiverse.com/thing:5234489
I'm quite happy with the setup. It is a little noisier in the enclosure than just on the table due to the melamine particle board panel vibrating while suspended on its plastic feet. I'll set it on foam and/or a paver eventually to improve this.
Good to hear some people are happy with their MK4.
I've been seeing so many complaints in the Prusa facebook groups from early adopters.
Personally I'm keeping my printer farm running MK3S printers for now, I'm gonna let everyone continue beta-testing the MK4 for another year or two before I splurge on a few factory assembled machines for the farm.
There's a reason my mk3s is the one I have as a fallback. It's really easy to service and I find it doesn't need a whole heck of a lot of tweaking. I imagine not having to set z height is nice but I haven't found the need to change it once it's dialed in as I pretty much only use the satin build plate and don't change nozzles often.
Dude, satin build plate for the win, it's amazing
I wish there were comparable products because I want that build surface for my voron, it's just a bit smaller than an xl so there'd be some overhang.
One thing to check on the factory models is the belt centering on the pulleys. Both my X and Y belts weren't centered correctly despite following the directions flawlessly, had to shim the motor mounts and also the printed Y motor holder where it mounts to the frame. Seems to be a common issue.
Hopefully the factory can find a good workaround for future revisions of the design. But gotta hand it to Prusa - they quickly respond when something needs be adjusted in the build. I remember the minor upgrades from the MK3s to the MK3s+ which seemed minor to some, but were huge for others (for me I see barely any difference in my farm, but hey I'm glad they made those changes if it increases the lifespan of the rails/bearings, etc).