On the plus side, REALLY good first-layer adhesion...

[hubrigant]

On the minus side, the stupid part ripped off a chunk of the borosilicate glass plate

Talk about a bummer! I've only had the thing up and running for less than a week, and now I've already got to replace the plate?

[geneb]

Flip it over. It still has a good side left.

g.

[hubrigant]

Wouldn't there be thermal transfer problems around the chip?

[Tonkabot]

you could fill it with thermal grease if you had to. It will probably work not to terribly just flipping it.

[Captain Starfish]

I ran mine flipped over for months without a problem.

Might wanna back off on the abs juice though - thin it down, or apply it over a layer of tape or gluestick.

[BenTheRighteous]

I've only had the thing up and running for less than a week, and now I've already got to replace the plate?

I dropped a screwdriver on mine after about the same timeframe. That suuuuucked.

The plate wasn't completely broken - just cracked - so I tried to keep using it. However, the constant heat cycling expanded the crack until the entire plate broke in half.

If you try to keep using yours, best of luck, but keep a close eye on it!

[Audin]

And once you have chips in both sides you can move on to printing around the smaller ones!

[TekNick]

On the minus side, the stupid part ripped off a chunk of the borosilicate glass plate

Talk about a bummer! I've only had the thing up and running for less than a week, and now I've already got to replace the plate?

I'm with you, the exact same thing just happened to me this evening. I didn't think I was using that much ABS slurry either, any less and I lose bed adhesion in the corners of my parts...

[BenTheRighteous]

Well this just happened to me too, actually! Was using the removal tool to pry off a part, was stuck on there pretty good, and when it finally popped off I noticed a piece of the underside was really bumpy and shiny. I'm thinking, what the heck is this? Some kind of weird plastic bubble where the plastic didn't cool?

...then I noticed a same-sized gouge missing from the glass plate. Nooooooo! And to top it all off, SeeMeCNC is out of 310mm plates! Argh!

[BenTheRighteous]

Ok, I'm starting to get concerned about this behavior. This has happened 2 more times (3 times in a row actually), my boro plate now has 3 separate chips missing out of it.

The first time it was just a small chip, and I wrote it off as a coincidence/nuisance.

The second time I was trying to remove a print while the plate was fully hot. That chip was a lot bigger and I thought maybe the plate's integrity was somehow weakened by the heat, so I wrote it off as a learning experience and resolved to not remove parts until they were fully cool. I also flipped the plate over to print on the remaining smooth side at this point.

The third time, I let the part and plate fully cool before I tried to remove the part. The part came off without any resistance at all but it brought a huge chunk of glass with it. The glass must've broken during cooling; definitely wasn't my fault this time. The part ran the full length of the bed and brought almost as much glass with it. My plate is now totally unusable.

I ordered some new plates from SMC but I want to track down the cause of the broken glass. My adhesion method was the "dissolve purple glue stick in water" trick that there's another thread going on about recently. It's just glue stick in water - pretty thick - perhaps too thick? But glue stick all by itself worked without ever breaking the glass so I don't see how adding a bit of water could really change up its properties this much. Not like I'm putting any other additives like alcohol, soap, rubber cement, or whatever...

Am I justified in blaming the glue stick mix? Or is it just that once a boro plate starts to go, it's pretty much garbage? The plate worked OK for about 2 months, the glue stick / water mix worked alright for about 2 weeks before this. Then suddenly starting 2 days ago, chip after chip after chip.

Any ideas?

EDIT: One other thought I had was that I also increased the bed temperature from 100 to 120 recently. But that should be no problem for the glass, right?

[Mac The Knife]

I've had it happen to one of my plates, I wrote it off as the plate being scratched from my razor blade scraper. I figured the scratches were creating stress.

[McSlappy]

Yeah when I switched to watered-down glue stick I printed a large flat object and pulled of a pieced just like this.... Then it was downhill from there. I swapped to a new plate last week or so (the benefits of having stock eh?) and so far there's been none of it. I wrote it off as being an old plate with thousands of hours of print time....

Then again I know someone else who did the same with a new plate printing Bridge.... Dunno.. Hope it's not a common issue.

[BenTheRighteous]

I'm thinking when I get the replacement plate from SMC, I'm going to try covering it with blue painter's tape before applying the glue mix. That way, if something's going to be ripped apart, hopefully it will be the tape instead of the glass.

[BenTheRighteous]

Well that sure worked. I just covered my shiny new build plate with blue painter's tape, then coated it with purple glue mix, and printed a small part out of nylon.

This part is bonded to the platform so well that it is absolutely shredding the tape while I'm trying to get it pried off!

While this is probably effective protection against another chipped glass incident, I don't see myself reapplying fresh tape and glue every single print. Going to have to think of another long-term solution...

[jdurand]

Well, I just had my glass plate pop off a chip. The odd thing is I wasn't super-glueing things down. Elmer's blue glue stick dissolved in water and painted on with a foam brush. Stuff sticks but not STICKS. This time, after the plate cooled down I picked up the part I had printed and my wife asked what was on the bottom of it. Looked, big glass chip. &^%$#@! Especially as I broke the plate on my Afinia yesterday, first time since I got the printer (few years ago). I must have insulted a glass god or something.

Any ideas why this would chip when I'm not hacking and scraping at it? Haven't hammered on it or anything.

Anyway, going to clean up the plate and flip it over. Also buying a cast aluminum FLAT disk to try in place of the glass. A 3/8" thick plate is only $14* but I will have to reduce the size a bit on my mill.

* surplus flat aluminum plates left over from making large bearings. They have literally TONS of it.
http://www.sandsmachine.com/alumweb.htm

Please don't buy all of it before I can call them tomorrow.

[BenTheRighteous]

Judging by the number of complaints about chipped build plates, I'm gonna guess SMC just had a dud batch of glass.

I ordered new ones after mine chipped and they've held up great. (Ordered 2 just in case but have only had the one on the printer ever)

I put PEI on the glass which A.) is awesome all by itself, but also B.) protects the glass. I don't think the new plates will chip as easily as the old ones anyways but I still recommend PEI, the stuff is awesome.