This is the same one that was linked in the PEI thread (viewtopic.php?f=36&t=7452).

mhackney wrote:The size is nominal 12x12 but that is quite a bit undersized. I'd get it replaced. If you can live with it, centering it s a good idea.
davec3275 wrote:mhackney wrote:The size is nominal 12x12 but that is quite a bit undersized. I'd get it replaced. If you can live with it, centering it s a good idea.
I looked into replacing it and unfortunately I missed the return window by 2 days. Tempted to order another, but worried it won't fit either. I saw some reviews on Amazon and some have had issues with sizes not being as advertised. I would rather it fit exactly.
mhackney wrote:The problem is that it will vary from batch to batch. I've ordered at least 15 sheets from Amazon and they have all been just right for the borosilicate glass diameter. I've also bought 4 sheets from McMaster and they were fine too. I don't recall seeing a +/- 1" tolerance, that is really not acceptable for this material.
KAS wrote:I'm on my second sheet in six months, both don't fit the glass fully (amazon .040)
ccavanaugh wrote:KAS wrote:I'm on my second sheet in six months, both don't fit the glass fully (amazon .040)
4 sheets from amazon also that won't fit either.
JFettig wrote:You really don't need to cover 100% of it. Your plate is actually larger than 12" anyway, closer to 12.25"
You also can't print all the way to the edges either. Yes it would be nice but its not completely necessary.
mhackney wrote:I haven't had any problems at 250° C probing and I've done quite a bit of it. Like you said, the touch is instantaneous so I think that prevents any issues.