Printer down, replacement parts and upgrades (and question on MK3S->MK3S+ x-axis)!
Hi,
I bought an MK3S kit last July, but I didn't get around to building it until about May of this year I think, for Christmas, my wife got me the MK3S to MK3S+ kit, but I never got around to fit most of it on the basis of "if it ain't broke".
I did do a couple of mods over the intervening time, super pinder and a y axis belt mods, but I strayed from going anything else that would have resulted in me having to go through calibrating everything again.
So everything has been going fine, until last week when I had a blockage and the filament snapped, I tried a few things but ended up having to dismantle the extruder. Even with the hotend out, I was unable to remove the stuck filament and in the end I had to remove the PTFE tube with a reasonable amount of force, once I'd freed the PTFE, the blocking filament just fell out, I believe I had suffered heat creep which resulted in this who chain of events.
I replaced the PTFE with a spare, reassembled the hotend, and tried printing again. Now I was getting blobs of filament, I couldn't work out what was going on and I thought it was the filament I was printing with (that had caused the initial jam), so I switched to black PLA, and at first glance, it seemed better, but then I started getting "bogeys" of the previous filament, often hours into the print and it clearly wasn't happy, so I knew it was time to strip down.
I realized now that filament was leaking from the top of the block and would make its way down eventually to the print and resulted in the issues I was seeing, I knew it needed a much deeper delve to fix the problem.
It seemed logical, that while the printer was in this state that I may as well perform the rest of the upgrades in the box, so I did everything barring the x-axis, this seems like it's going to be a reasonable amount of work to bring the machine fully up to MK3S+ spec and it's not covered in the manual, in fact, 7 or so months ago prusa themselves commented in the manual saying "it's coming soon" and it's still not there, so the answer is to look at the MK3S+ assembly guide an work back, it's fairly obvious that the Z top mounts need to be removed and the 2 Y motors unscrewed end then unscrew the rods to get the x carriage + x ends off the rods.
I'd then be left with the whole X assembly intact there I would need to remove the rods from the ends so I could replace them with the new ends, before pushing the rods back in.
Can anybody explain exactly what steps need to happen to make the job easy, I'm by no means sure if I'm going to bother, this change out of all the others seems to be the most intensive for a no/small gain. Does the carriage need to come off the ends, or is it possible to perform this upgrade with the extruder still mounted to the rods?
My other question stems from the hotend issues I had, I have had to order a replacement heater block, the one I had when the leak occurred ended up with filament in the threads both for the nozzle and the heatbreak, I couldn't find an easy way of removing this hardened filament, I tried various methods but in the end, decided that I'd get a replacement block because I'd be starting from a much better place, I dismantled the block and cleaned up the heater cartridge ready for inserting into the replacement block.
So, the question on that is, is there something you use to clean up when you get problems as I did, obviously the block needs heating to clean out the threads, but space is limited on getting in there and cleaning them up, and at the same time I want to avoid damaging the thread and ending up creating a situation where it's going to leak no matter what. I did see mention of a thread die being used, but clearly, you'd need to be very careful with that and even then, I'm wondering if that would leave everything pristine, my thoughts here are that if any filament gets left behind then I might be creating problems further down the line.
I believe I had suffered heat creep which resulted in this who chain of events.
Just as likely; you may have left it on preheat too long.
I started getting "bogeys" of the previous filament, often hours into the print and it clearly wasn't happy, so I knew it was time to strip down.
Take a look at: https://help.prusa3d.com/en/article/changing-or-replacing-the-nozzle-mk2-5s-mk3s-mk3s_2069
Pay particular attention to "Final inspection" - it's also possible to buy cheap nozzles that do not quite meet the correct thread dimensions.
Can anybody explain exactly what steps need to happen to make the job easy,
https://help.prusa3d.com/en/category/original-prusa-i3-mk3-mk3s-to-mk3s-upgrade_1183
I'm by no means sure if I'm going to bother, this change out of all the others seems to be the most intensive for a no/small gain.
If your printer is working well you don't need it. It simplifies the initial build and fixes some issues with an iffy build.
is there something you use to clean up when you get problems as I did, obviously the block needs heating to clean out the threads,
If you work with a preheated hotend (careful) it should be straightforward with only surface cleaning. Once used, cold replacement is almost impossible.
Cheerio,
Fixed
Just as likely; you may have left it on preheat too long.
I've never left the machine on pre-heat, in fact I've never used pre-heat, I just power it on via octoprint and then that deals with everything (including cooldown), it only heats when I send a print to it.
Take a look at: https://help.prusa3d.com/en/article/changing-or-replacing-the-nozzle-mk2-5s-mk3s-mk3s_2069
Pay particular attention to "Final inspection" - it's also possible to buy cheap nozzles that do not quite meet the correct thread dimensions.
The bogeys were a symptom of the issue that resulted in me dismantling again, the threads inside the block had filament on them and my question was about getting that out, I didn't have the right tool to hand or know what the right tool is, so I ended up replacing the block because that allowed me to start fresh.
I'm using the original heatbreak & heatsink, the block was replaced as was the nozzle.
I did replace the nozzle with an e3d one that I bought when I got the printer (but it took me nearly a year from receiving the kit to actually building it), but, it was a nozzle-x and I think this is what was causing me further issues. I subsequently replaced that with a plain old brass nozzle and.....I'm back up and running.
The nozzle-x *may* have been ok, I printed out a torque wrench and I was having awful troubles getting it to print, the model itself seems to be a bit of a nightmare to print, small thin features resulted in blobs of filament-forming and getting pushed around, this meant cosmetically there were a few issues after I eventually got one to print, the other issue was because of these blobs sometimes they form and the nozzle would hit it and due to the way the print is done it would knock it free from the bed.
When I switched to the brass nozzle, it seemed a bit cleaner, but the finish in places on the top was not pretty, but I think that's a combo of 100% in fill, small features, and thin features.
Since then, I've re-printed a few other things (including the torque calibration bar which was also 100% infill, but doesn't have the small or thin features and it came out perfect) including some spare printer parts, they've all come out beautifully now!
I really appreciate the response and pointers, I've learned a few things through this whole experience, the first is that nozzle changes aren't as scary as I thought they'd be after watching videos and reading descriptions, I now know how the hotend should be assembled.
It's great to have the printer back up and running now