Printing straight onto unheated glass?

So I had an old scanner lying around just begging to be dismantled, and I finally had some free time to do just that. And I turned up trumps with some uncracked glass ^_^

But at the moment my printers running PLA onto blue painters tape, not a particularly nice bottom finish, but it does the job. So I was thinking, with exams coming round within the month, I haven't got enought time to make a full heated bed config and fit it.

So is it possible to just simply plop the glass straight onto the bed with a couple of bulldog clips and a quick wipe with some acetone? Would the PLA stick? I mean the heat has no real factor in stickiness does it? Just to stop warping of large parts? Which I'm not really doing at the moment :v)

Ollie.

No, I'm sorry to say, PLA will not stick at all to cold glass. Try heating the end of a piece of filament with a lighter and press it onto the glass, and you'll see. You're better off using blue tape until you build a heated bed.

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-Nudel
Blog with RepRap Comic

Jus' tried it. Bummer :/

Gimme a month and I'll make one. Exams take priority unfortunately :/

Ollie

If you're looking for an alternative to blue tape without moving to a heated bed, try a piece of acrylic. I've had great results printing PLA directly on the surface.

Nudel Wrote:
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> No, I'm sorry to say, PLA will not stick at all to
> cold glass.

That's strange, mine sticks good enought for small parts.

miso Wrote:
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> > No, I'm sorry to say, PLA will not stick at all

> That's strange, mine sticks good enought for small parts.

Then you must be better at calibrating than me. If my heated bed drops below 40C everything snaps off if the head catch on the part ever so little. If I start the print with too low bed temperature, the beginning of the skirt doesn't stick to the platform and drags everything off at the first or second layer.

Perhaps sanding the glass, extruding at higher temperature, printing slower and using lift could help?

Not saying OP shouldn't try it if he wants, but in my experience it won't be more reliable than masking tape or acrylic.

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-Nudel
Blog with RepRap Comic

PLA sticks very well on a copier film. Rough side up. Just use double sided tape between glass and film.

I haven't been able to get PLA to stick to cold glass, but glass at 60 deg C works great!

The parts stick great and when cooled they crackle and pop right off with a nice glassy finish.

before I had a heated bed I was printing on wood with masking tape.

Very small parts will stick to glass because the PLA heats up the glass slightly locally. As soon as you get more than a few layers up though the locally heated glass cools and the part detaches. Sanded glass may work better unheated, I'm not sure.

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Try using spray adhesive
I had good results with cold surface using frosted glass and spray adhesive. Only problem is bottom is sticky But you can clean it.

has anyone tried floor wax with acrylic? I use it for heated prints with abs on glass for best results, but it does work for cold glass as well on small objects.

just poor some onto the glass, and wipe off excess. let it dry for 5 or ten minutes.

on large heated objects the parts pop off the bed when cooled, i think from the glass size changing.


, for parts that are not heated, just twist and part will come loose.

I think I remember a conversation about plain glass vs plate glass...

Either way, I use picture frame glass that was custom cut to my size and it sticks very well for small-med size parts (about the size of a prusa x-carriage)

Anything bigger and I need to use masking tape. The nice part of glass however, is the nice glossy surface it leaves on the part, so I try to when convenient.

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How much spray adhesive do you use vedran?

I'd suggest you look up "Heat deflection temperature" so you better understand the underlying problem, that is, before you waste your time discovering the hard way what the plastics industry has known for decades.