In Other News...So... out of sheer annoyance, I went over my Tornado and tightened the belts again... this time to what I consider "excessive". I also went over the model again, generating neoBracket RevC with all the characters debossed to only 0.40mm depth; looks a lot better in layer view. Printing now at 0.1mm LH, 60mm/s speed with supports.
I'll drop some pics on y'all in the AM.
Cheers,
mnem
*OLAL*
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=623485;image)
I got up this morning at the sparrow's fart, excitedly hoping to see a world of difference in the ghosting... and promptly turned around and went back to bed.
![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
Request for KP push denied. Use a heat gun to warm the bed adequately and as long as its clean, you wont need anything else. I used painters tape for along time, then saw the heat gun trick in a YT video. Next jump will be LALO so pack light and bring your fins, extraction will be 2.5k up the beach head.
After thinking about your comment, it dawned on me that every time I've had issues with liftup and the related deformation, it has been at the edges of the bed. So I spent some time over my morning cuppa observing my bed during an extended PREHEAT.
One of the things that sold me on this printer over the CR10 was the 120VAC bed heater; as the people who actually bothered to use it before they reviewed it said, it comes up to temp
"HOLY FUCKING ASSCRACKERS!" fast. Like 90-120 SECONDS fast.
![WTF? :wtf:](https://www.eevblog.com/forum/Smileys/default/wtf2.gif)
Temp with mirror surface however, appears to be a whole different animal. After 5 min or so, it measures ~10°C less than setpoint, so I usually set temp to 70° for PLA. That's how I did it for all my little shelf legs with stellar results.
![ThumbsUp :-+](https://www.eevblog.com/forum/Smileys/default/icon_smile_thumbsup.gif)
Now comes the interesting part... I realized this morning that I'd always just given it a quick measure right in the middle of the bed, because that's where the PTC sensor is underneath. Occasionally I'd measure while it was printing... and that was usually right around the same as my prior measurements until around 30-60 minutes into a print; where it slowly creeped up towards set temp of 70°. But while it was printing, I NEVER measured in the middle, because the print was in the way. DUH.
![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
So today I clean the surface to make sure hairspray residue doesn't affect accuracy, and measured an approximate 16 x 16 grid repeatedly across the entire mirror bed, watching it heat up. Difference between outer edges and center was as much as 10°. This took more than 30 min to start to equalize. Well, hell. After an hour it was 65-70° across the bed.
So why? Lots of possible causes... First and most obvious, the fact I'm using the mirror glass. Added mass, plus dry contact means thermal transfer is less than optimal. Also unknown is how the mirror affects thermal transfer and measurement; though performance indicates that when my IR gun says the surface measures between 60-70°, my work sticks, so I'm thinking that's pretty damn close to right. (And THAT makes this TOTALLY TEA-related...
![Laughing :-DD](https://www.eevblog.com/forum/Smileys/default/smiley_laughing.gif)
) Also, there's the clone "Build-Tak" print surface that comes on these; I never removed it because I preferred the added layer of protection for the cooktop-style ceramic glass underneath. So a third layer to compound things.
Great... now I have shedloads of stuff to think about. But I want to print.
![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
So I swallow my pride, take your advice and dig out my big 1800W heat gun... and heat the outer edges of the bed for a few minutes. It comes up to a nice even 65° across the glass with very little work, and I start the print.
Now printing another copy with all the same settings as the first "successful" iteration #2... only rotated so main body is in Y axis. An hour later there's zero curling, and the entire bed measures 63-65°.
![Clapping :clap:](https://www.eevblog.com/forum/Smileys/default/clap.gif)
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=623515;image)
Now to see if rotating it did any good with the ghosting...
[EDIT] meh. Maybe slightly better. Not enough to finish it. Now printing Rev8 at 30mm/sec.
[/EDIT] mnem
![](http://i1183.photobucket.com/albums/x462/mnemennth/A-_OK-_Rocket-_Surgery.jpg)