Why does ABS stick differently to different types of glass?

There is a test for how well ABS sticks to glass... to predict adherence, lay a thin amount of ABS juice on the glass, and then scratch it with a finger nail...

Some glasses it will be impossible to scratch ABS off and some it will all flake off easily.

I just got some tinted glass that was lying on the roadside, and it sticks 20 times better than picture frame glass and Ikea mirror glass, i don't understand chemically the reason for it.

Does someone have a friendly glass cutting shop near them? could they do a quantitative version of the ABS adherence test and test it on many different glasses with different tints and so on? Why does it bond to non silicone tinctures of glass better?

Edited 1 time(s). Last edit at 03/29/2015 06:10AM by skynetprinter.

Interesting observation. Float glass will have a thin coating of tin just on one side.
Tinted glass could be just a surface coating or could be homogeneous throughout the glass I think.

if it is tinted on one side that means you have a plastic coating on one side, that would explain why it sticks but if that is the case you can remove it with a razor blade and it is not very durable of a coating at all.

I do know that old greenhouse glass (3mm) worked splendidly for a while without even ABS juice but got poorer and poorer adhesion no matter how it was cleaned until it had been left on a shed roof for most of the summer. After long exposure to the sun (UV??) and rain it was good again. Things which had failed to clean and re-establish adhesion included acetone, Fairy washing up liquid, very fine wire wool and many combinations along with boiling water to rinse off.

Mike

Kind of wondering why it would matter, regular glass (home depot), tempered glass and borosilicate glass all work fine for me with no problems using a 3mm skirt and 3 light layers of aqua net hair spray at 105c first layer and 100c for the rest of the print. I can print an entire bed worth of parts and have none lift the corners even a bit.

@lunarkingdom You are printing on " 3 light layers of aqua net hair spray", not on glass. My only attempt with hairspray (Boots extra hold) was a failure - it might as well have been oil that I was printing on.
When it works, printing directly on glass is very good indeed. Hot adhesion is excellent and the print pops off when cold. the problem is that the printing seems to poison the glass and later prints don't adhere at all well no matter how cleaned. ABS slurry would be good if it were more predictable - some prints lift at the corners, others can even tear chunks out of the glass before separating.

Right but like I said, on 3 different types of readily available glass you can print ABS with a 3mm skirt and 3 light layers of aqua net hair spray at 105c first layer and 100c for the rest of your print and be successful 99.99% of the time so why bother with anything else? The exact aqua net hairspray I use is "extra super hold" in the purple can:



Why do anything other than what works when you have been given a recipe for success?

Edited 7 time(s). Last edit at 04/01/2015 10:05AM by lunarkingdom.

Thought I would add I use an ice pack for when you get hurt I bought at the pharmacy on my print as soon as I turn off the hot bed, it rapidly cools down the print and the bed and the thermal diffusivity caused by doing that pops the print off in about 5-7 minutes or by the time it gets the printer bed to around 20-25C. Once again, works every time!

Quote
lunarkingdom
.....
Why do anything other than what works when you have been given a recipe for success?

There could be many reasons.

The particular brand of hairspray that you recommend may not be available in other parts of the world.
There may be some other reason why adhesion is below par. e.g., skynetprinter mentioned that ABS slurry worked much better on his found tinted glass than on other glasses.
There may be a procedural error or miss-calibration in something so that first bed thicknesses or stickiness of the extruded filament is wrong.

Many people have recommended one solution or another, but none of them work for everybody. It seems not unreasonable to try to find the variables that effect bare glass before applying band-aid.

Mike

Don't forget that not all and is the same either.

A sheet of scanner glass with nichrome on the back and gluestick on the top does extremely well for me. No need for anytning else and the gluestick lasts many prints.

The problem is not what works, but what stops it working for everybody.
I have discovered one bad thing - using extra strong kitchen tissues such as these

with Acetone will leave a very anti-stick layer. Even Wolfbite won't wet the glass.

Mike

I have found that it can vary with the filament brand, too, I usually buy Filamex brand ABS which sticks to borosilicate with a coating of ABS slug fairly well most of the time, but when I got a good deal on some Makerfarm ABS, I found that it is (a) larger diameter (2.94mm vs. 2.85mm for the Filamex), and (b) sticks to hairspray better than ABS slug.

I have had bad luck with regular glass - it always cracks in half when I get up to 120 degrees. I haven't had a problem with borosilicate glass.

Quote
Rich K.
I have had bad luck with regular glass - it always cracks in half when I get up to 120 degrees. I haven't had a problem with borosilicate glass.

Was the glass on top of aluminium plate, and if so, how thick was the plate? Regular float glass should be OK if it is heated evenly.

---

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].

Quote
leadinglights
I do know that old greenhouse glass (3mm) worked splendidly for a while without even ABS juice but got poorer and poorer adhesion no matter how it was cleaned until it had been left on a shed roof for most of the summer. After long exposure to the sun (UV??) and rain it was good again. Things which had failed to clean and re-establish adhesion included acetone, Fairy washing up liquid, very fine wire wool and many combinations along with boiling water to rinse off.

Mike

This made me think... I wonder if the adhesion issue is:

1. Use the glass with the ABS and eventually any micro scratches are filled in over time.
2. Restoring the glass outside could increase the micro scratches (or restore them if you will) resulting in a more textured surface that is conducive to sticking.

Just a thought.

Edited 1 time(s). Last edit at 04/13/2015 08:55PM by Viper97.

Here is a page that gives the properties of different types of glass, all glass printbeds must be different:



from this website

you can buy aquanet in europe from Amazon, which also has it's ingredients, it's pretty interesting. amazing what women put on themselves.
Aquanet extra super strong: Water (Aqua), Dimethyl Ether, SD Alcohol 40 B (Alcohol Denat), VA/Crotonates/Vinyl Neodecanoate Copolymer, Acrylates Crosspolymer, Amino Methyl Propanol, Sodium Benzoate, Cyclohexylamine, Triethyl Citrate, Cyclopentasiloxane, Masking Fragrance (Parfum) (Parfum)

Perhaps the stickiness of the glass is related to it's ionization and ability to hold a static charge? definately the less SiO2 the better.

Edited 1 time(s). Last edit at 04/14/2015 05:53AM by skynetprinter.

it boils down to molecular structure. But chasing the glass is a waste of time now. It is well known and has been for a long time to be a pain in the butt, and one that many accept is par for the course, using substrates like glue sticks, hairspray, absjuice and the like.

However, Non substrate surfaces are the way forward. In other words, materials that have adherence properties to 3d printed materials without the use of substrate. And an ideal material will be light, thin, and adhered to the glass one time, the plastic deposited unto will stick until the surface cools down, at which point the printed part is easily removed without tack or adhesion, and with a nice smooth clean bottom And they all lived happily ever after, the end! Simples.

I am pretty certain that Mutley3D is right, it does boil down to molecular structure. I also think that he is wrong about chasing the glass being a waste of time - if the thing that goes wrong with the surface molecular structure can be defeated then glass is pretty much as good as it gets.

Having said that, I am presently experimenting with Wolfbite and my experience is that it behave exactly like good plain glass - that is, excellent adhesion when hot with no edge curling and the print simply lifting off when it has cooled down. I hope that it remains reliable for all ABS prints.

Reliability and predictability is what is required when you have a 32 hour print on the go. Having a Neanderthal skull fall off after 27 hours is disappointing to put it mildly.

Mike

LeadingLights - Wolfbite is something you have to buy and apply. In other words you are dependant on it. I am talking about NO ADHESIVES (or paint /spray on substrate) EVER! The issues with glass cannot be defeated, reprap has been trying since day dot, and it is still problematic. Its ok for some, who tolerate blemishing or staining, and no doubt some are able to use something that leaves no mark. I havent. There is Sital Glass, but it is not a magic bullet in my view.

I havent used any substrate for nearly 9 months now, and i print a whole variety of materials. I have one single print surface fitted to each machine, and i never physically touch it, because i have no need to, only the parts that are printed that simply lift of, with perfect bottom surfaces. I print bottom layers at up to 100mms. Not 10-40mms. Bottom layers can add quite a bit to print times.

This also means that i do not have to relevel the bed on regular occassion just becuase it was disturbed when removing the glass to remove the stuck print (although this raises other questions of machine design - another topic)

Mutley3D, Can I ask what the non-substrate surface that you are printing on is?

The need to buy something like Wolfbite is less important than the fact that it is made to promote adhesion of ABS prints to glass. The makeshift solutions rely on the manufacturer keeping the same recipe - whether hairspray, Kapton film, glue stick or whatever - there is nothing in the specification about promoting adhesion of prints and the manufacturer will always reserve the right to change the recipe at any time. So far I have come across cleaning products which will poison any surface, Blue builders tape that PLA treated as untouchable, different Kapton tapes of widely varying adhesions and of course hairspray with all the stickiness of Vaseline.

I am quite intrigued by your mention of blemishes and staining with glass. All I have seen is success with a smooth bottom; partial success with a smooth bottom surrounded by a convex lifted (but still smooth) area and of course abject failure - but no staining.

Mike

staining or blemishing on the bottom surface when using substrates. this vaires depending on the substrate used.

In the EU i didn't find any recommended hairsprays to try out, and i have seen that Taft 5 from schwartzcopf perhaps? except that the guy doesnt demonstrate the end result, perhaps it was only 3 layers high. Hunting down glass is pretty good, there is often alot lying about in waste sites and it's every time a different chemistry, i am learning to cut with the hot straight element of the oven or a string wicked in a flammable solvent in order to heat and cut stright lines.
[www.youtube.com]