Get some high temperature thermal compound such as boron nitrate paste and it will help to kind of “glue” it in.
Personally, I think it’s design flaw. And It’s cost me 2 stickers and three hot ends.
Your right, its not the best design, but with a little look at it wit work good.
are you using the snapmaker filament that came in the box?
i think you are the only person ive seen who has an issue to this nature.
you shouldnt need to be trading hotends out frequently and if the print sheets are damaged, what reason is it?
what issues are you having with your prints exactly?
I see you say you think the filament is getting too hot, but beyond the issue with the thermistor, what are you seeing on your print bed that made you think to look at this?
i just want to make sure you are on the right path because i have different suspicions as to what may be going on
with that said, you can also get nozzles to swap out instead of the whole hotend. They are called mk8 nozzles and are dirt cheap on amazon.
for example., here is a box of 30 pcs for 11 dollarsn
The previous time I printed some test miniatures, aside from some stringiness, they printed fine.
This last time, the white filament extrusion is translucent and melted into the surface, making what printed impossible to remove from the sticker.
Here’s a picture. White filament isn’t supposed to look like this, and I’m not supposed to need to buy an extra supply of hot ends and stickers. Next print I’ll be using my third sticker (5th side) and 4th hot end, though a box do nozzles is not a bad idea.
I stopped the printing before it made a complete circuit of all the items. This is effectively the first slice, and the sticker is ruined. (The back side already has problems.
I believe other printers have much sturdier thermistor structures. I think the new assembly is easy to use, but the thermistor mount design is failing. If it falls out, could the temperature be far higher than indicated? Sure looks that way from my picture.
This printer was promoted as being easy to use, like an appliance. I’d simply like to see this redesigned to make it harder for the thermistor to detach and overheat.
I’m sorry, I missed your other question.
Yes, I’m using the white PLA filament that came with the Snapmaker A350. I haven’t even opened the other spools and won’t until I can get reasonably consistent results.
And I did order the nozzles. Thanks!
So looking at your picture…
I think we have many issues going on at once here.
It seems like you are being a little ambitious about how many things you are putting on your sheet at once, at least at this point - it takes time to get to where we can fill this thing up, theres a lot of tinkering that needs done before the prints start coming out like gold (but it will get there!)
It looks like you have a z-offset issue, the nozzle is too close to the bed which is not allowing the material to extrude out well.
on top of that, the snapmaker filament is really lousy, particularly the black that came in the snapmaker box (which fuses to the print sheet and ruins it as you are encountering), but i was just running some other snapmaker filament and while its certainly better, its still junk - clogging my nozzle and causing poor finish issues, even after a bake.
Now, you may be saying why does the print look good in some areas and not others?
Thats because the leveling of the bed doesnt account for the bed temperature, which will further warp the bed.
Here is what I feel you should be doing, right now:
Order something else filament wise. Hatchbox, amazon basics or better. No weird foreign chinese crap (at least not right now while we figure your issues out).
get yourself them nozzles we discussed, the boron nitride paste to hold the termistor in your hotend, and unfortunately a new print sheet it sounds like.
consider buying some magigoo for now, you wont need it full time, but just to help you get the print sheet seasoned - it will help with adhesion and release of parts too.
So, from here, I want you to get a fresh nozzle on your hotend (or new hotend if you desire), with some non snapmaker filament, loaded up and ready to go on your fresh print sticker
then i want you to go into the settings, for auto-leveling, and enable a 5 x 5 calibration grid.
then I want you to go to the controls and pre-heat the bed to about 65 degrees, and let it sit at temp for 10 minutes
then, i want you to do the calibration, and when we get to the end of it, i want you to have a little tension under your calibration card, and then bump it out an extra -.05mm
then i want you to print a calibration cube and lets see how it looks.
I think 205 is a good temp for most PLA, i usually go 200, with 60 degree heated bed
we have some other adjustments and things to do, but lets start there.
sound okay?
i went from more frusterated than you are to printing things like this:
2 Likes
Thanks for the feedback.
I’m already doing everything you suggested except I haven’t used the paste to glue in the thermistor, yet.
I already heat up the bed prior to calibration. I use the 5x5 calibration grid.
The picture shows a number of models and all looked like this. Looking from the end of the sticker directly at the print head, for orientation, the right side seems to be .01 higher than the left. I’ve used a level on the desk, which is level, and the cross arm, which is a bit less level, and the bed, which has different amounts of levelness across the bed.
I’ve used both a center bubble app on my smart phone, as well as a 12" level from the local hardware superstore.
I do need to take things apart and use a torque wrench and digital caliper while I put it back together with the level. I’ll let you know my results.
The extruded filament, as you can see in the picture, has been subjected to too much heat and has lost its integrity. I’ve seen the thermistor pop out of the little tube while I’m reassembling the print head and tried to replace it. I’m guessing that it just falls out after so much time.
The previous print was ok, other than being stringy. The miniatures, tiny robot tanks, are white on the map.
(https://www.dropbox.com/s/uha26d5jwrigkfg/IMG_0740.jpg?dl=0)
Miniatures for a game to send to my grandson
it doesnt look to me its got too much heat, it looks to me like its being smooshed too close to the print bed.
however, im not able to see it too closely as its just a snapshot to go off of, you have more time with the machine to know
with that said, its true the build plate is not particularly flat, and it changes as it gets warmer too, so some areas will work better than others. hence the suggestions above
i am currently waiting on some borosilicate glass to use as a bed, its being cut this week. then i have the challenge of having to level manually or rigging up a different way to trigger the sensor.
i actually ran a 11 x 11 (121 positions!) calibration with the bed heated a few minutes ago for the first time and im anxous to see if it helped any… if it does i can show you how to do that, you have to use gcode for that
It’ll be interesting to see how your glass works.
My quandary is that on both of my prints, I took great pains to set them up the same way, same measurements;
I think you just need to set the Z offset at the end higher and try it.
Its way to close I think, I think they said its better to end with a few .05 ups at the end.
Cheers
Chris
Thanks for the feedback.
What I did both times, the good run and the bad one - was to do the 5x5 calibration with the heated bed and then fine tune the Z by using two of the plastic rulers, until there was pull, then pull them out. Did the same thing both times.
The first time I did that it was fine. The second time I did that, it over melted it. Thinking about it, I did notice the interior of the enclosure was very warm on the second run, and I turned on the fan.
I think it’s got to be the thermistor. I’m waiting on the paste.
And it occurred to me that it would be a lot easier to remove stuck pla from a nozzle by removing the nozzle and placing it in a jar of acetone. Would something else dissolve it faster (without dissolving the brass or the glass)?
Acetone will not disolve PLA.
There is no safe substance to disolve PLA. There are some chemicals that can but its not really something you wana do.
If you heat the nozzle you should be able to wipe whats on the nozzle off relatively easy, you can get cleaning needles to clean the inside or preform a cold-pull method which you might need some nylon or something to do.
Just to elaborate on this a bit, PLA is a dissolved by solvents that also dissolve organic molecules, and since you are also made of organic molecules - many things that dissolve PLA risk also attacking you.
Ethyl acetate is relatively safe, at least safer than methylene chloride, and is used for PLA solvent smoothing sometimes. It would dissolve PLA on a nozzle.
I’ve used methylene chloride (dichloromethane) in the past and haven’t tried it on PA, yet. I wanted to start with safer things, of course.
I ordered some from Walmart and we’ll see how it works.
(Let me know if you want the MSDS)
Whatever you use, make sure it’s in a well ventilated area - you don’t want to be smelling anything ‘sweet’ smelling - if you can it’s not ventilated enough.
For DCM nitrile gloves are only for incidental contact only, it will percolate through the gloves and eventually melt. I have a set of thick butyl rubber gloves good enough for extended handling.
Ethyl acetate looks like 30 minutes of breakthrough for nitrile, which is better.
I wonder if the ethyl acetate will remove the coating on my coated microswiss nozzle
I can tell you’ve never had acrylic nails. 
Yes, absolutely, safety first. Even Hydrogen Dioxide can be poisonous in sufficient quantities.