What did you 3D print today?

Cleaning up my work bench and finding a place for everything so i created this little fellow.

 

Guys,

I know my school printer setup isn't ideal, but to help out the school I'm trying to trouble shoot any issues the printers are having to train the teachers this summer to be able to use them this year. I've narrowed problems we've been having down to files with a big footprint (roughly larger than 30mmx30mm) that have a hard time sticking to the platform, despite me going through an entire cailbiration routine with calibibrating the height on all corners and midpoints of all sides of the platform. I followed all the included instructions with the printer with no success and after googling and hearing someone mention the same thing, would there be a glue / spray that I could use to help the base or raft stick to the platform for my larger prints?

Here's one of the successful prints with the small footprint:



Here's one that would not stick.





Any advice is appreciated.

Thanks.

 

Just my drink ignorant ass shooting off, but that large first layer looks like too high of a z offset and possibly too low of a bed temperature.

That's throwing me though. I've not seen a small base print when a large base wouldn't. I usually get the opposite.

 

I would double check the bed material is compatible with the material being printed, and possibly up the plate temp too. If plate temp is too low and the filament is one that's prone to curling, it can be mitigated some with a higher bed temp.

For some filaments/beds glue helps and for others it doesn't really make a difference. If you're going to use glue, use a glue pen, the sticks are total pain to clean off the bed.

What material are you trying to to print?

 

So is the Z offset between the base plate and the first layer or between the first layer and subsequent layers? I calibrate the z / height right before every print with a piece of paper sliding under the extruder with a small amount of friction.

One thing I noticed is that the base plate is not consistently flat. It's like 1/32" plastic and the tutorial that came with the printer shows the person bending it to make the print pop off which will make it less flat. I just use the scraper they included and try to flick an edge off or just slowly rock the print back and forth instead of bending the base plate.

Is the bed temperature the actual bed that's changing temperature or the temperature of the filament coming out on the first layer?

 

To be honest I didn't even know the plate can heat up nor do I know if I can modify that in the print options I'm given in the software I got from the school. Maybe that's an option that I could find on the touch screen menu on the printer itself, but I'll have to check on Monday.




Here's the filament I believe I'm using.



Appreciate it

 

Z offset is between bed and first layer. That first layer is tricky- especially if your bed isn't perfectly flat. Heck, I'm on an aftermarket bed that is a machined aluminum block and it still has a curve to it. My printer, however, has a probe that maps the bed surface and then compensates for it.

But from what I can see, your first layer isn't showing that right kind of "squish". And if a small base is printing successfully while a large print isn't, it's possible that your bed is warped.




See if you can find and download a "first layer test".

It will look similar to this.


Do a few runs of that until you can get consistency in all corners and the center. A successful print means your bed is truly level.


... As for temperature, your printer should have two heat controls- one for filament and one for bed. Filament controls the temperature of the melted plastic right before it gets extruded, bed controls the heat of the bed. The bed needs to be hot to make a naturally sticky surface. Many materials recommend 60 degrees C, but I personally like to run mine really hot, in the neighborhood of 80 degrees.

 

A warped bed is what I've been leaning towards too, however I have absolutely no experience with a 3D printer until I was asked to run these for the school this year.

Here's the calibration video I was following, the link should go right to that part of the video. There's a "fine tuning" calibration where it also does the middle of each side and all 4 corners. I have not seen noticable improvement when doing that over the calibration of only the center of the plate.

https://youtu.be/kY90P420oxc?t=169

Also, here's a link to the section of the video where he bends the plate to get the print to release. It didn't look good to me even before I started doing anything with the machine and less so now that I have been getting an understanding of how it may harm our larger prints.

https://youtu.be/kY90P420oxc?t=373

I'll look for a first layer test. What / is there a standard file type for printers?

I'll look into increasing the bed temp.

Here are a few more pictures of failed prints - the first one was the piece that was supposed to be in the back, middle.



This is another one that took 3 tries:



And a couple examples of bigger prints with small footprints that came out pretty well:





The part that messed up was just a support piece here.

 

Turn the bed heat up to at least 70c, your screen shot shows 50c.
The print temp of 220 is fine, mine does the first layer at 220 then 215 from then on. Heat on the bed and a flat first layer are critical to having it stick and turn out well. It's the foundation for the entire print.
Some prints need an extra adhesive layer.
PVA (dilute Elmers glue) works the best and cleans off easy.
Cheap aerosol hair spray works well.
Regular old glue stick works too, may require a bit of soaking to bet it to release.
I had issues with adhesion when I started too. The software with my printer was set at 50c as well. Advice from this thread prompted me to turn it up and that was the key.
Subsequent software updates have finally got the settings in line with what they should have been to begin with.

 

Oof I didn't see but it's right there. Ok I'll increase the bed temperature on the bigger prints. I'll try a glue pen / hair spray / glue stick or something else recommended here if it's still not sticking.

 

I'd start with just increasing the bed temp first and printing the test prints first to see how they turn out. I rarely use any glues anymore, mainly just for small footprint things that stand tall and are on the bed for long periods of time.
You can design your own test prints, just lay out a few 40mm x 60mm rectangles at .5mm thick to see the first layer and the top layers.
Heating element on mine is in the center of the bed. The edges and corners of the bed can be "cool spots" and lead to edges lifting, so don't be afraid to bump up the bed temp if the center sticks well and the edges don't.. Brims are helpful to keep the edge down and easy to trim off.

 

Wow, I have been thinking in the back of my head (Even though I know it's wrong by now) that 3d printing still has a long way to go before I'd consider using it as a hobbyist.

This post proves me wrong. That looks amazing.

 

Yeah, 60C bed is the lowest I've ever used. Clean the surface after each print. I've used the Elmer's Glue sticks, and water seemed to be the best for cleaning it off.

 

Glue is usually my absolute last resort, and 90% of the time I can go back and work out the underlying issue that caused me to use it as a crutch in the first place.

Often right before I'm about to start an overnight print with a lot of complicated support, I'll level my bed (using the sheet of paper method) and then I'll take 5 minutes to print a simple first layer test. There are many designs out there, I like this one for it's speed and simplicity:

https://www.thingiverse.com/thing:2879437

It looks like this.




Then I check each corner of each square for adhesion, and I look at the layer lines to make sure that they are sufficiently even in width, that they are overlapping consistently, and that no individual line looks "rounded" or is lifting off, and similarly, no line is spread so thin that it looks pinched.







^^^ If I can print that simple thing without imperfections, then a larger print should present no issues. As Snusnu said, the first layer is the critical layer. If a flaw shows up there, it only gets amplified.

It's not sexy, but I would practice with first layer tests, and I would start my bed temperature at 80.

 

Embarrassing as it sounds, I don’t have any drawing software. Are there any decent free programs out there for Mac or PC - really free not a gimmick.

 

Autodesk still has a personal license for Fusion 360 that's free. You can pretty much do everything you need in it.

https://www.autodesk.com/products/fusion-360/personal

 

Free and easy, has tutorials to get started.
https://www.tinkercad.com/

 

Printed some bed cubby covers to cut down the dust in the bed.

 

Dang I just had to go find that file. That's on deck next.

 

I've had the files for months and always forget about them.

I just went to install these and realized I printed the wrong number of parts. I need to print one more hinge cover for it to work.