Print Failed --- Clean Your Resin Vat...

[Sumner]

On a recent print.....



….. I forgot to put supports under the bunks that extend out the sides and they partially failed.



I fixed the supports and almost went on to printing the newly supported prints but........... felt the missing parts of the failed print might be in the resin vat. I never empty the vat as I only use one resin for everything (Siraya Tech 'Build' Sonic Grey). I add to it and cover it between prints, usually off the printer in case it started having a slow leak.

I decided some time back to always empty/strain the vat if a print had fails so strained the vat into a cottage cheese container as show above. The filters I've had for years for when I was painting my street rod and are really cheap so cheap insurance vs. having to replace the FEP film. I haven't had it happen but can see where if there is semi-cured resin bits from a failed print in the resin at the beginning of the print when the build plate goes all the way down to the bottom of the vat it could push those pieces into the FEP film and possibly through it.



After emptying the vat and as I wiped it clean with a paper towel I did indeed find a number of semi-cured resin bits that matched the missing parts on the print. The ones above were only some of them.



I was able to pick the failed print parts out and used the strainer a second time to pour the resin back into the vat. Ran the next print with no problems and the prints came our fine.

When I started resin printer I used the putty type knife that came with the printer to remove prints. Hated how hard it was to use so moved onto razor blades (real ones) and then the plastic ones. Better results but still not easy in my mind removing prints.

Then I saw some one using/recommending the paint knife shown above. It is so much easier than the previous methods. I'd never would go back and bet you wouldn't either and would regret you waited so long to get one. I've heard of these braking but hasn't happened to me and fearing it might I bought a spare.

 When removing the support pick up the edge of the support with the wider part of the knife towards the handle, not the tip. You will find it very easy to pick up the edge of a support on the end and then slide the knife under it and work it towards the other end of the print and slide it off.

I bought the knife ( HERE ) but there are a number of other sources for it also.

Sumner

[CNR5529]

Oh man... I have punctured the fep due to the tiniest little shrapnel floating around in the vat. Not only did it puncture the fep, but liquid resin flowed under the vat and then cured to the lcd screen! Fortunately the screen didnt crack, Phrozen was able to walk me through salvaging the screen with a cleaning procedure, and the cured resin actually sealed the fep hole so it wasnt a catastrophic failure. Still, as you say, hard lesson to learn. I now know filtering is cheap insurance. I also now expose the whole screen if I have a failure, as it makes a sheet that is easy to peel off the fep, and any debris gets embedded in the sheet (do this after letting the resin blobs settle down to the bottom). You basically collect all the bits in one neat package. If you plan it well, you can even set a piece of scrap support down there before exposing to act as a handle to start peeling.

[Chris333]

You do know you can expose the whole screen at once to bond all of that scrap to one thin sheet that peels right off? Don't even need to drain the vat.

[robert3985]

You do know you can expose the whole screen at once to bond all of that scrap to one thin sheet that peels right off? Don't even need to drain the vat.

This is what I do.  Peels right off with all that loose stuff stuck to it if you do it after the resin has settled for a while. 

Keep your old, fairly tall supports (so they're tall enough to stick out of the resin) and putting one of them in the corner of the vat before exposing the entire FEP surface allows for easy removal of the cured resin sheet this technique produces.

But, I'm not getting any failures.  I'm pretty crazy about Anycubic ABS-Like Resin 2 Pro, and I fill my build plate up, getting hundreds of parts in one 1hr, 17min printing...and with some parts, over a thousand in about the same print time...with zero fails. Maybe I'm just lucky, but I think I'm getting the hang of it.

Photo (4) - Latest run of 304 ea "Original" UP Snow Shields for E8/E9's washed & dry, waiting to be removed from my build plate before curing...not a single failure, so nothing in my vat to punch holes in my NFEP:


I finally decided Lychee Slicer Pro was the way to go, and with about a $16 per month subscription, it has certainly been worth the cost even though the included Filament Printer slicer is trash (and I'll never use it anyway).

I do the LED Check for 30 seconds after about 10 prints, or immediately after I spot ANY failures on what comes out of my resin vat...which hasn't happened in almost a year now.  Easy to do, and very effective.

Cheerio!
Bob Gilmore

[John]

Great advice - I use these paint strainers all the time .. I routinely filter the resin in the vat at least once every few days, and always after a failed print ..
Some other tips:

1) I don't leave resin in the vat for a long time - it sometimes separates into a white substance on the bottom - always drain when this happens ..
2) Resin can be too cold and too hot - too hot it increases the chance of a failure .. I try to keep it around 23-24C
3) I use a mixing spatula - the soft kind to stir resin in the vat before I print for the first time .. this also helps check for junk in the bottom of the vat
4) Always shake your resin bottle before pouring . just in case to get an even mixture ..
5) I usually re-level the build plate once a month or so ..

There are more tips, but most of you know all this already .. this is just what I do in my work flow

[Sumner]

You do know you can expose the whole screen at once to bond all of that scrap to one thin sheet that peels right off? Don't even need to drain the vat.

Yep and thanks to everyone for the additional information.  The post was a copy and past from my 'designs one can print' page on my website....

https://1fatgmc.com/RailRoad/3D-Printer/3D-Printer-Index.html

.... and was meant to remind new printers the need to check their resin vat if prints fail.  I didn't document options for removing failed prints but maybe I'll go back and revise the page to offer some solutions like what have been suggested here. 

Personally I always filter the resin if I believe there might be failed parts just in case they might still be suspended in the resin and not laying on the bottom of the vat.  Just makes me feel better I guess. 

Like Robert this was my first failed print in months and it was my fault as I put in all the supports for the first time and forgot some obvious ones that were needed.  Normally Chitubox does a great job on 'auto' with me adding a few others but I didn't like how it had put in a number of supports for this print and spent more time deleting those and adding than just putting in all.  But then when I went the route I did and failed to put some in that kind of back-fired  .

Sumner

[GGNInNScale]

Hi to all    I had a FEP failure that made a mess.  I ran too many prints, I guess.  So, after I cleaned up the mess, mostly in the base, I made two adjustments.  One, I make a small dam out of modeling clay and form the dam around the main lift mechanism.  This keeps spills out of the machine guts.  Second, I put 3M tape around the edge of the plastic protection shield outside of the vat area.  The tape gives you about ten seconds to react to a spill before the resin leaches under the tape and under the protection shield. 

[JeffB]

Great advice - I use these paint strainers all the time .. I routinely filter the resin in the vat at least once every few days, and always after a failed print ..
Some other tips:

1) I don't leave resin in the vat for a long time - it sometimes separates into a white substance on the bottom - always drain when this happens ..
2) Resin can be too cold and too hot - too hot it increases the chance of a failure .. I try to keep it around 23-24C
3) I use a mixing spatula - the soft kind to stir resin in the vat before I print for the first time .. this also helps check for junk in the bottom of the vat
4) Always shake your resin bottle before pouring . just in case to get an even mixture ..
5) I usually re-level the build plate once a month or so ..

There are more tips, but most of you know all this already .. this is just what I do in my work flow

Good tips...  But as a counterpoint, I rarely remove the resin from the vat and almost never relevel the build plate. 

  I printed several rafts of parts on my own Photon I a few weeks ago.  The resin in the vat had sat there for nearly a year since the last printing session.  I stirred up the resin for about 5 minutes using the plastic scraper that comes with the machine, then with a 1" nylon bristle brush that I use for cleaning prints. 

  Have done similar with my Mini-4K and will be doing the same on my Mini-8K sometime today.  No problems with the prints sticking or printing successfully.

  That said, you're advice IS sound...

  Heating the resin, or keeping it warm is very advisable, and helps a great deal with printing very fine details.  If it's cold in my workshop, I now resort to heating the resin with a heat gun prior to starting a print.  Once it gets going, the heat from the machine keeps it at a good temperature for the rest of the process.

Jeff

[Lemosteam]

You do know you can expose the whole screen at once to bond all of that scrap to one thin sheet that peels right off? Don't even need to drain the vat.

Did this for the first time after a failed print.  Me happy man.