Hair spray on the glass plate (UM2)

[blackomega 2]

Has anyone tried this in place of the glue stick, blue tape, etc?

I find, despite people saying it isn't required, that a sticky plate works great for the first layer.

Always in search of a quick way of doing it.

 

[oswaldo-salzano 2]

For me, it works very well (even better if you combine w/ 60C heated buildplate).

 

[jonnybischof 60]

I've only printed PLA for now (some ABS prints but these were never really good and I didn't put much effort into them), and just simply heating the bed has always gotten me good results. I don't use any kind of glue or liquid, nor tape.

I sometimes clean the bed with a paper cloth and alcohol. But the most important thing is a good levelling:

The nozzle must be absolutely flush with the build plate if there is nothing on the build plate (like tape or a layer of glue or something). The UM1's four-point levelling system makes this a real PITA. I don't know about the UM2, I believe it has a three point levelling system?

Then, you need to find the right temperature for your material, and that means both nozzle and bed temperatures. I had to play around quite a bit until I found something that really worked (sharing would be of no use to you, because I have a different build plate and different filament...).

And you need exactly the right amount of material flow. If you have underextrusion on the first layer, then it will fall apart when the shrinking forces start to show up. If you have overextrusion, then the plastic won't stick well at all (at least that's the case for me). This stands in contrary to printing on blue tape, where overextrusion just pushes the material into the tape better. That does NOT work with glass, instead the plastic gets smeared around which makes it stick poorly. Maybe need confirmation on this - that's something I observed but haven't actually read about before.

For finding the right parameters, I usually do the following:

Print something which has a large, square base. Make a simple 5x5 cm rectangle for example. and use a lot of brim (like 20 lines or even more).

Then you can observe the print and adjust parameters if it's not coming out well. Always stay on the first layer until you get a very good first layer. Don't even try to print further upwards as long as the first layer is not good.

You can set up your initial layer flow very well when printing the brim. Usually, the first few lines will slightly underextrude because the plastic can escape to both sides. But the third or fourth line should already be pretty much flush. You can play around with the flow settings while it prints, but you should only change the flow amount every 4 to 5 lines because it takes a while until it really adjusts. The printer might actually "carry" over excess plastic from previous lines to the adjacent one over several lines. This also applies vertically - if you have massive over- or underextrusion, then you can't adjust your flow rate within one layer, because you'll first need to fill up the gaps (or deal with the excess plastic) from the previous layer. You'll have to observe how it "develops" over several layers.

From the first layer upwards, you shouldn't have too many problems anyways, as long as the print stays stuck to the build plate.

/edit:

note that I have a Basalt build plate, not plain glass. The Basalt is slightly porous which makes it better than glass in terms of adhesion, but this should not be a game-changing factor...

/edit2:

If your levelling is not good (which is the case for me - working on that...), then you'll probably have to go with different flow rates for the first layer and the following layers. That's bad, so better see to it that your levelling is very good in the first place.

/edit3:

Reading through all the sh..tuff I just wrote, I noticed this may seem like a lot of effort. But if you actually get it to work, then you can forget about wasting gluesticks or anything else and just hit the "print" button and get good results, which come off the build plate all by themselves as soon as it's cooled down all the way, and you get a very good surface quality for the bottom.

There are probably some filaments which will just NOT print on bare glass no matter what - but for a good quality PLA this definetly works. Faberdashery for example is excellent: I've never had anything stuck to my build plate as hard as faberdashery filament, but it popped off the build plate as soon as it was cooled down below 30°C.

 

[yellowshark 153]

Yup I only use hairspray with my glass plate. Certainly for something say 5cm * 5cm, I would not use a brim just a couple of skirts to get the extruder stabilised. That is extra strength hairspray - cheapest I can find with bed 50-60c. With PLA if I am doing a lot of printing I will wash the plate and re-apply every few days. With nylon I will refresh during the day - and Taulman say you cannot print on glass hehe