I'm really liking 1/4 inch window glass...great surface quality, good thermal properties,

Mike_Miller · January 3, 2015, 3:00pm

I’m really liking 1/4 inch window glass…great surface quality, good thermal properties, nice and flat. (This is 160 mm^2)

William_Frick · January 3, 2015, 4:27pm

I’ve got pieces that I swap out between prints when doing production parts. Any surface prep you need can just wash or peel off when you use different filaments.

Mike_Miller · January 3, 2015, 4:30pm

I’m having great luck with hairspray and 90C on glass…nice thing about hairspray is that it’s a water soluble layer.

William_Frick · January 3, 2015, 4:31pm

So is PVA for use with nylons

Brandon_Satterfield · January 3, 2015, 4:43pm

@Mike_Miller so not liking the garolite?

Mike_Miller · January 3, 2015, 4:44pm

I suspect it needs a flat surface to provide support. I had it hanging by four corners and after placing glass on it in a fit of desperation, noticed it was sagging in the middle.

Eclsnowman · January 3, 2015, 4:54pm

I am a big fan of glass too.

Brandon_Satterfield · January 3, 2015, 5:42pm

@Mike_Miller what thickness did you choose and how many heat cycles appx have you ran it through?

Eclsnowman · January 3, 2015, 6:46pm

@Brandon_Satterfield I have had my standard window glass through hundreds of heat up cycles. It is almost 17" x17" on HercuLien and I print almost exclusively abs on that machine… So that’s at 110C bed temp.

I did have a piece of double strength tempered glass blow up on me back when my machine was a corexy. I think tempered glass should be avoided since it is in tension by design as a result of the temper heat teat process.

Also I no longer use those black spring clips since they impart point load stress to the glass. Now I just lightly blue tape down the glass at two edges so the glass can expand as it sees fit during the heat up cycle.

SirGeekALot · January 4, 2015, 2:08am

I use windows glass at 60c with glue stick to print PLA. It almost sticks too well! I can’t remember offhand if I tried it with ABS or if I was still using plain kapton (I haven’t printed with ABS in a while now).

Mike_Miller · January 4, 2015, 2:09am

I’ll switch back to pla when I’m happy with my print head solution. (I’m not yet happy.)

Mike_Miller · January 4, 2015, 2:12am

@Brandon_Satterfield plain ol 1/4 inch plate glass you’d find in a window. $22 for two cut 12"x12"

Brandon_Satterfield · January 4, 2015, 4:51am

Thanks guys, I have been diving deep into the realm of this print bed thing. I may have something but almost impossible for only me to do all the testing required. I may soon just ask for you guys addy to send a bed for testing, but not confirmed yet.

Thanks for the input.

Mike_Miller · January 4, 2015, 1:59pm

One of my biggest problems was the decision to go big. I wanted a 12x12 un-impeded bed, and figured 13.5-13.75 for the support structure would be a good idea…but the whole world uses 12" as the standard dimension to cut things to. Which means I’m either 1.5" short, or 11.5" too large (Which, hey, I can deal with, but it’s a lot of wastage.)

Brandon_Satterfield · January 4, 2015, 2:37pm

@Mike_Miller what I have been doing is buying large sheets of whatever material I’m experimenting with and cutting it on the CNC. This has allowed me to make round, 12x14, etc beds without loosing much.
Completely understand your point of view though, not worth a rebuild but a pain in either direction.