[SOLVED] Slaggy Prints With Flaps Everywhere -- Possible background exposure?

[flameswithin]

Hey everyone. Honestly, I haven't been able to get reliable results from our solus for several months now. My coworkers have basically written the machine off and gone back to using our Revo mills full time. Even I am having a hard time defending the machine anymore.

We had a broken filter between our lamp and optical engine, but we just got that fixed. I sent our projector (Optoma HD37) in to the manufacturer, who replaced the optical engine and put in a brand new lamp. I got the projector back, removed the UV filter on the lamp, and got the latest edition of the user manual from Emil to set everything up. After a bad print today, I double checked all our projector settings and they are correct. I checked the graphics settings on our computer, and they are correct.

I just put a new film on recently and am using a **brand new** bottle of resin. Basically everything is set up correctly, configured correctly, and all components are new and fresh, and I can't get good results.

We're using Cherry resin. Since we had a brand new lamp in our projector, I reset the exposure times to their default. I barely got a successful print; the layers didn't adhere well and there was a lot of separation in the print. I started bumping the exposure time up until I got a solid print. It's currently set to 4.6s.

Attached are images of what I got today. I would love some help. This machine is no longer productive for us to use and has just become a useless time sink.

[mongerdesigns]

Is that the cherry resin? Looks like the proto resin.

The cherry resin is more finicky to work with. The emerald is an improvement on it.

However I suggest waiting for our own castable resin that will be released in the beginning of June.

When you got your projector back, did you go in and set all the correct settings in the menu? Seems like a bit of overcuring happening.

[mongerdesigns]

What is the purpose of the huge logs inside the ring there?

[Jewelermdt]

What is the purpose of the huge logs inside the ring there?

Was thinking the same thing. That is overkill. Maybe just two needed.

[flameswithin]

It is Cherry resin, purchased just a week ago directly from B9. So unless they're buying your Proto resin and repackaging it, it's Cherry.

We used Emerald resin for a while, but switched back to Cherry because we truly got the best casting results with Cherry. Better than Emerald and Better than the Yellow "casting" resin from B9.

Waiting for yet another resin that may or may not be the problem next month simply isn't an option. I can't tell the owner of the company that this expensive machine is going to sit idle while we wait.

Blaming the resin isn't really a satisfactory answer either as we have gotten great results with the Cherry resin in the past, and other Solus owners use it as well.

Yes, as I said in my original post, when I got the projector back, I specifically asked Emil for the latest edition of the user manual to ensure that I had everything set up correctly. Just this morning, I have checked again. The dynamic range on our computer is set to Full RGB. The display mode is set to "Reference," Brightness - 0, Contrast - 15, Sharpness - 15, Gamma - 1.8, Lamp Mode - ECO, High Altitude - On, Power Mode - Active.

The "logs" inside the ring, as you describe them, are a support strategy we came up with in our shop back when we were getting print failures constantly. We found that putting a diagonal waffle-like grid inside our ring shanks gave us a VASTLY more reliable and stronger grow. This is a big, heavy, awkward shaped ring, and a structure like this has been useful for this type of ring in the past. I tried the automatically generated supports from inside the Contour software, but the scrawny "chicken leg" looking support it generated looked to me like a *guaranteed* print fail, so I did it my way.

So, now that I have addressed your first line of questions, what else could be causing all this slag? Thanks.

[mongerdesigns]

Send me that stl file and I'll see if I can grow it using "chicken leg" supports.

[flameswithin]

I have spent all morning reading through posts here in the H&T forum to get ideas on how to diagnose and fix the problem. I developed a suspicion that my film tension might be wrong. So, I installed the vat with *no* resin and ran a print to watch the crystal-drop action. And, it didn't look like the vat was dipping as much as it should. So, I tightened the vat screws down and using a clean PEC pad, I ran my finger firmly around the edge of the crystal to stretch the film out. I loosened the vat screws to their normal tension and ran another print. It failed less than 1/3 of the way in.

Attached are photos of the failed prints. The slaggy flashing is still an issue.

When we get a failed print, we print a large solid rectangle, which cures all the resin in the area, so instead of having to clean up little bits of failed models, we can pull off the cured resin in one single piece. Take a look at this picture -- this is the drained vat after running this. You can clearly see the flashing around the edge of the rectangle.

So, the next thing I decided to do was re-calibrate my build plate. Even though I fully believed it was calibrated correctly, I figured someone would suggest I do it again anyway. Also attached here is a photo of the tissue paper I use for my calibration. As you can see it is .05mm. Unless I am mistaken, this corresponds to the recommended 50 micron paper thickness for calibrating the build plate.

I decided to make a quick video of our vat in action during a "dry" print. Please feel free to take a look and let me know if you think my film tension is off: VIDEO!

I have a new print running as I type this to see if the new plate calibration helps any. I'd still love to hear anyone's suggestions or feedback. Thanks.

[mongerdesigns]

That gap is way too much. See how your vat is moving on one side during the tilt?

Your gap should be close to 1mm.

[M-Williams]

Well assuming that your machine is nicely calibrated, and there is no issue with your file, than I would say it is a film tension issue . Even the printed part is a poor quality result for a solus standard, unles your are printing at 42 . I'm a Hardcore cherry resin user, you can get some amazing casting results if the resin is nicely cured. Also your inside supports are way too overwhelming. I have no need for an inside support,when there is no overhang. My 2 cents. Marc

[nzfinescale]

Not sure I'm expert enough to jump in here, but I've certainly had enough failures to sympathise!

First thing to note is that when I do everything right the results are stunning (Solus proto or B9 emerald). 'Right' covers a fairly broad range - it isn't that tight a process, but there are certainly places where you can go wrong.

In your case that floating vat will be the problem. Mine doesn't float at all, the thumbscrews are snugged tight and the vat is hard down. My understanding is that it isn't supposed to move (jump in Emil and tell me if I'm wrong!). I did play with a tight film and using the thumbscrews to adjust tension - but it was not a success. If you snug the screws right down then you do have to get the film tension right to start with - I just follow Mark's video.

I've been doing this through a couple of litres of resin now and detail levels are excellent.

Hope this helps.

Lawrence