PLA on glass

I have been printing with confidence on my Replicator 2 for some time now, but the inevitable has happened. The acrylic build plate has warped so badly that I can only print in the middle. I thought I would solve the problem by making a glass build plate, which I have done. My problem now is getting the PLA to stick to the surface.
I do not have a heated bed and have tried all I can think of to resolve the issue. My print settings are; nozzle temp 230, nozzle size 0.5, resolution 0.2.
Any suggestions welcomed.

I initially had problems getting PLA to stick to my bed, albeit a heated bed. It was down to surface contamination, a tiny amount of dust and/or grease is enough. I now use supermarket branded vinegar based glass cleaner and kitchen roll before EVERY print.

PLA will not stick to cold glass. You need to coat it with something, such as blue painters tape or PLA adhesive (e.g. glue stick). Or invest in a heated bed.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Hairspray. my number one since years. You can also dremel, sand or sandblast the glass that also helps. Or buy one of these new printing pads

After fighting the "PLA directly on heated glass" fight for way too long, I finally tried a thin layer of stick glue (Elmer's/UHU school glue.) on clean glass. Works reliably, washes off easily with water. I wash and apply a thin layer every couple prints. Some people have had similar success with a thin layer of diluted PVA (Elmer's liquid glue.)

---

RepRapPro Tricolour Mendel Legacy with self-printed and upgraded X/Y axes, new mini extruders.

Hairspray is you friend, I'm using a spray from the Aldi supermarket.
The hairspray will make PLA stick to a warm and cold bed, is easy to apply and clean, cheap and has a nice smell!
As an added bonus you can fix your hair while printing! :p

Quote
sungod3k
Hairspray. my number one since years. You can also dremel, sand or sandblast the glass that also helps. Or buy one of these new printing pads

Do not sand glass, this is a bad idea!
I just read in an other thread that people did this and their glass started to chip and crack.

In my experience, printing PLA direct on glass depends on several factors:

1. The filament. Some filaments will print direct on glass, others do not. I am in the UK and I now buy all my PLA from eBay supplier Galactic Warehouse (aka latest-bidder) because I find I can print direct to glass with it. I tried 2 other filament suppliers but found the filament would not adhere to glass. The filament supplied with an Ormerod kit from RepRapPro was also OK for printing direct on glass.

2. The bed temperature. I set it to 65C, although the temperature on top of the glass is closer to 55C.

3. Surface preparation. Wash the glass in hot soapy water initially. After that, avoid finger-marking it. Wipe it with distilled vinegar before each print. Do not use organic solvents, in my experience they make adhesion worse.

I tried glass with a ground surface, but the filament did not adhere.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

My 2p worth -

My heated bed is not finished. Impatient to print, I tried ordinary masking tape on cold aluminium plate and finger-smeared some neat PVA glue across it.

My PLA sticks great but not so fierce to be a problem. The coating has lasted fine for about a dozen prints so far.

Glass(window) cleaner and bed set at 65°C.
From time to time I redo the sheets of glass (after 1 or 2 weeks), depending if some new finger-marks are present.
After cleaning and rinsing do not wipe it with a regular towel. Our towels are 'contaminated' with washing-softener <--- (don't know the correct english name for the product used in the last run of washing machines, please correct me if I'm wrong)
If you use a towel a greasy-ish layer will be added to the sheet of glass and adhesiveness is gone.
Only drawback, it works so well you have to wait until the heatbed is almost at roomtemp. to remove parts.

Quote
chriske
After cleaning and rinsing do not wipe it with a regular towel. Our towels are 'contaminated' with washing-softener <--- (don't know the correct english name for the product used in the last run of washing machines, please correct me if I'm wrong). If you use a towel a greasy-ish layer will be added to the sheet of glass and adhesiveness is gone.

Good catch, I hadn't thought of that (and it's called "fabric conditioner" here in the UK). I leave the glass in a rack to drain, and finish drying it with paper towel if necessary.

Quote
chriske
Only drawback, it works so well you have to wait until the heatbed is almost at roomtemp. to remove parts.

Yes, which is why I have several glass plates so that I can start a new print immediately. Sometimes I have to put the glass+print in the freezer to get them separated.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I Also use paper towel to wipe of water.
Maybe I should buy a few extra sheets of glass, good idea, thanks...!