borosilicate glass

robo3d isn't including any build surface for the abs model so here is what you can use.

borosilicate glass, it will give you an even build surface and provide protection for your heat bed so you don't scratch it up from constant removal of prints. this is only needed if you have the abs heated model

parts links
10x10 1/8" thick boro glass
part# 8476K21
http://www.mcmaster.com/#standard-borosilicate-glass/=mc7y5s

binder clips
for holding down your boro glass to the heatbed (not sure of thickness needed yet till we receive our printers) http://www.officedepot.com/catalog/search.do?Ntt=binder clips

 

not many people have the tools to drill holes through glass, also you want it easy to remove for cleaning, some like the option to remove it while its cooling, and swap in another glass and start another print.

 

To bad mcmaster doesn't ship to Canada Hopefully RoBo will offer something.

 

i'll let the picture speak for ifself, this regular glass broke under heat stress. due to flexing heat bed (all heatbeds flex some during heating and cooling), boro is stronger and wont break under this type of stress.

 

an alternative, is to use 1/8" (3mm) aluminum sheet, provided you can find a super flat sheet that doesn't warp when heated.

ive seen some people use the aluminum as a heat spreader then add the boro glass on top, the aluminum evens out the heat distribution of the heat bed providing a more constant temperature throughout the print surface.

downside of boro glass is that it doesn't distribute the heat evenly, from the center to the outside there is 10+ degree measurable difference.

photo below of my testing. probe attached to center of heatbed and another probe near the outside. meter shows 12+ degree difference from center to the outside.


I did another test with the aluminum plate under the boro glass and the center and outside glass temperatures stayed within +-2 degrees of each other.

 

my boro glass arrived today. nice to have mcmastercarr not too far away.

 

nothing that's it. should be all that i need for the robo to be ready to print out of the box. for now anyway

 

Cambo... Do you think having a 1/4" piece of Garolite over the heating pad will work? I am wanting to print with nylon and don't want to be constantly changing and adjusting my print bed. I was hoping the heat would radiate through the garolite for printing ABS on top of the garolite.

 

I have no idea, i haven't tried it.

It is thicker so it would probably take longer to heat up if anything.

 

We are going to find out "hopefully" soon.... I'm hoping they start shipping printers next week.

 

I don't think they will be shipping in April.

 

:-(

 

Hello, what clips to use aluminum plate + boro glass, you have a size that's what happens when the bed moves?

 

Hello, binder clips used for aluminum plate + borosilicate glass, you have a size that's what happens when the bed moves?

 

here is what i'm doing with mine.http://forums.robo3dprinter.com/index.php?threads/heatbed-and-bed-leveling.841/

 

Hello on your plate borosilicate glass, the thickness is 3.3 mm?
Cordially