1

Topic: glass bed questions

To people suggesting to use glass on top of the Solidoodle 4 aluminum bed,

1) How thick should the glass be? What is the risk of glass cracking from the temperature?

2) Does the filament stick to the glass bed as it sticks to the kapton on the aluminum plate right now?
Or do I need to cover the glass with something to make it stick?

3) If yes, what kind of chemical is doing the magic? So I'll check if the hairspray or whatever I'm getting has it or not.

Thanks.

2

Re: glass bed questions

I have been using regular window glass from the hardware store.  standard thickness  8 x 8 IIRC about 1/8 in. held on with medium
binder clips.  (1 -1/4 in) box of 12 binder clips  and a can of Auqua net Hair spray from wall mart .  IIRC the whole lot cost me about $ 5 .

A piece of borosilicate glass would be more heat shock resistant McMaster Car 847K18  8 x 8  x 1/4   $24.62

I use the hair spray for printing PLA. do not know what chemical but aqua net seems to be the brand of choice.
Tin

Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura

3 (edited by jaques 2014-10-18 13:14:37)

Re: glass bed questions

Thanks man.

I got a 1/8 thick glass cut to a 8x8 inch piece.

I'm printing with ABS. Do I need to use a hairspray or some other binder if I'm printing in ABS? Solidoodle sells glass plates on their site but they do nit mention anything.

We dont have Aquanet in the non USA.
Will other hairsprays work? That's why i was asking what chemical was doing the trick.
The hairspray I got contains

Alcohol Denat.
Butane
Isobutane
Propane
PEG-12 Dimethicone
Parfum
Aqua
Linalool
Hydroxisohexyl 3-Cyclohexene Carboxaldehyde
Alpha Isomethyl Ionone
Cintronellol

Also, how much hairspray do you spray on the glass?
And do you do it before every print?
Do you need to clean the glass before a new print?

4

Re: glass bed questions

Yes on the hairspray, and just a light dusting should do the trick.

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

5 (edited by jaques 2014-10-18 20:47:20)

Re: glass bed questions

What were you answering by suggesting to do dusting?
I tried the hairspray, and from first impresssion it just adds some rough texture to the clear glass. is that what's making the filament stick?

6

Re: glass bed questions

I think the magic ingredient in Aqua Net is vinyl (at least I believe I've seen that mentioned somewhere on these boards). It shows up as the 4th ingredient on my can as VA/CROTONATES/VINYL NEODECANOATE COPOLYMER :-).

7

Re: glass bed questions

jaques wrote:

What were you answering by suggesting to do dusting?

You don't need a hole lot of spray on the glass, just enough to give it a light coating.

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

8

Re: glass bed questions

Thanks. By my initial tests the generic hairspray I got made the print stick very strongly to the glass bed.

So do I need to clean the glass and spray again for every print?

9

Re: glass bed questions

jaques wrote:

Thanks. By my initial tests the generic hairspray I got made the print stick very strongly to the glass bed.

So do I need to clean the glass and spray again for every print?

Nah, the more goop that builds up, the better it works. I haven't cleaned my glass bed in months. For very large parts, I find the hairspray isn't enough to prevent the part from curling up. What always works for me is printing the first layer slowly with a wide brim, and while the brim is going down, paint some "secret sauce" on the corners and maybe a few other spots if it is really large (the slow printing lets you get a dauber or brush in and out without being hit by the print head :-).

The secret sauce formula is basically 50/50 acetone and MEK with a little ABS dissolved in it.

Of course, this sticks really really well. I usually have to let the bed cool off for a long time before I can get the part off. (And I don't clean off the residue left from the secret sauce either).

10

Re: glass bed questions

So do I need to clean the glass and spray again for every print?

I have hd my printer about 10 weeks have yet to clean the glass and have sprayed the glass about 4 times.
but I expect if you do lots of prits you may need to fresen up the surface more oftem.

Tin

Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura

11

Re: glass bed questions

Thanks for all the information.
One question which I forgot to ask: should the bed temperature be different when using a glass bed?
It's 120 right now.

12

Re: glass bed questions

For  ABS it may benefit you to use borosilicate glass. Since the ABS needs the heat to prevent warping /lifting.  As mentioned I have had good results with plain window glass but I am running PLA and a bed temp of around 60 c.   
as far as bed temp use what is needed for the material being printed. 
Tin

Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura

13

Re: glass bed questions

I'm using an old cut up mirror at 95 temp.  Once print is done, I swap out mirror's and let the print on the mirror cool down to room temp. Then the prints usually pop right off without any pressure.

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

14

Re: glass bed questions

thanks

15 (edited by jagowilson 2014-10-20 22:45:11)

Re: glass bed questions

I can't believe you folks don't clean your glass frequently. I don't like how filthy it gets. I also feel like I get better adhesion on a clean sheet with fresh hairspray, but that's just me. Dirty glass can also make your first layer look ugly/have bumps if it's really bad.

One alternative I haven't seen anyone mention is elmer's glue sticks--the purple ones. Sticks great, but your first layer will have to be sanded afterwards because I've found the glue stops it from being perfectly smooth. I use this method if I'm printing something large that will have a lot of free-standing edges, which are the number one cause of warping in my experience. They act like heat sink fins and cool the bottom layer really quick. When I'm up and running I need to print a fan shroud to get some filament cooling going on. With that and my E3D on the way, I'm going to have a crazy amount of fans on that 12V rail.

I've had prints still not want to come off after an extended period. Freezer = instant removal. Just let the glass get to room temp first, and put down a few paper towels with the glass to keep away direct contact with the freezer floor. If you ever have to use that scraper that came with the printer, you're doing it wrong IMO.