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Anyone else expericing this problem

I’m having what I call Scum in the Resin Tray around prints and other areas. It’s not on all prints but there more than it should be. I have to filter the resin after almost all prints. The machine has been cleaned, glass and mirror and was working great then this came back again after just a few prints.Resin%20Scum--(0)

Assuming Form2. There are more mirrors than just the one big one. Did you clean them all? This kind of fuzziness in a print is always because the laser is defocused/scattered by dirty optics.

Yes, 2 Form2’s with the same issue. Kind of figured that was what was needed. Done it before and it’s not a lot of fun doing. I do have the cleaning kit from FL so that’ll help. Thanks for the input.

Well, I took both Form 2 units apart, in sequence that is. Cleaned up any spilled resin and then cleaned the galvo mirror, main mirror and the glass. Put a new orange cover on each machine so they now look new. No more messy cover with cracks and spills on the inside. Look like new machines.
First print done on newest unit and look real good but there was a slight bit of the scum. Second machine, oldest, is now running it’s first job after the cleaning. We’ll see how it goes.

AHHhgggg as Charlie Brown would say.
I’ve cleaned both my Form 2 printers, the Galvo mirrors, main mirror and glass. First print went well then SCUM again. I cleaned it again, everything, ran a job and SCUM on the build pate. Oh, this is soooo much fun NOT>

How old are these printers? FL can see how much laser power they’re putting out via the printer’s phone-home telemetry. It might be that the lasers are just getting tired. Of course, cleaning the mirrors is also tricky, and they can be easily damaged. And anything that “dirties up” the beam produces similar effects in the resin.

One is fairly new, about 3 years. The other is one of the first Form 2 printers.

One thing I’ve noticed is spacing between rafts. If the spacing is close, 3/8" then I get the scum on the build plate. If I can move the parts at least a 1/2" apart then there is none. I’ve ended up having to drain the resin and filter it on almost every print.

The newer Form 2 is running fairly good when the above is taken into consideration. Thing is a lot of my stuff needs more rafts on the build plate to produce the order quantity.

I’ll have to look into replacing the lasers. Not familiar with the “Phone Home Telemetry”. Need to look into that as well.

I do a lot of manufacturing for a model railroad kit manufacture and the quantities are high and lots of them at times. I sold him 2/3rds of my company 3 years ago but he doesn’t do 3D printing.

It seems unlikely to me that the lasers start flaring in two of your machines at the same time.
Maybe it is the resin? The first layer gets overexposed, so variance in resin composition can be visible there.

The Resin is ALW and I’ve been using the same resin for over 4 years. I have already contacted the company and they say the formula has not changed.

Doesn’t mean you don’t have a spoiled batch. I agree it’s unlikely both lasers would start to misbehave the same way at the same time. Very unlikely. But one thing that does change on both at the same time is the resin you’re using. I assumed you were using FL resin. Now I realize it’s not, I think that’s where you need to focus your efforts. Trying different resin is a lot cheaper/easier than replacing lasers.

I’ve been using ALW resin for going on 5 years and it’s run just as well as FL resin.
I thought it might be the resin but was assured by the manufacture that nothing had changed in the formula.
I’d be out of business if I had to use FL resin. The cost is way to high at double what I pay for ALW.

It’s strange that if parts are close together on the build plate that’s when I get the scumming. I just printing some large parts that I was able to space apart and thee was just a small spot of scum where two were a bit closer. That would tend to indicate that when the raft is being exposed there is flash some how. I’ve also noticed that the raft base closest to the build plate is wider than it should be for the first few layers then goes to the size it should be which leaves a thin skirt. Almost like reflection off the build plate?

I think the laser power is highest for the bases. So if the resin is curing just a bit too easily, the bases is where it’s most likely to be evident. Especially if the bases are spaced close together. The exposure to scattered laser light is doubled in those regions between the closely spaced bases and you get some partially cured resin as a result.

It’s not a question of whether the manufacturer changed the formulation, it’s whether the batch you got was formulated correctly. No process is 100% perfect. The actual mix of chemicals in the resin is going to vary a little from batch to batch. On average, the resin you buy should be about the same. But if you buy enough, eventually you have to get one that’s at the “edge” of whatever their process limits were, and it’s different enough to not perform as well for you. Or maybe the resin was exposed to environmental extremes (really hot or really cold) in transit and that’s changed its properties…

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I did the “Call Home” deal and FL tells me the lasers are weak? BUT…
Yesterday the tabs on my orange resin tray broke so I discarded it. I move the LT resin tray from the newer printer to the older one then installed a new LT tray in the newer printer. GUESS WHAT…
All the issues cleared up with the new resin tray but still in the older one. The older LT tray. The bottom is clean and no digs in the inner surface, it’s a good tray or should be. Question is what’s causing the issue and is it something to do with the manufacturing of those trays???

I’m SERIOUSLY looking at moving away from the Form 2 printers and getting an Anycubic Mono X printer.
I have volume printing to do and can’t keep reprinting over and over to get around this issue. Some order are for over 100 small parts and to do that in multiple prints is time consuming. Didn’t have that problem in the past.

Have you checked the heat-maps on the dashboard for those trays? I know LT trays are supost to have a long life, but there must be a limit.

I run Open Mode as I use ALW resins. Not sure there’s any need for heat as this resin has always run well.

Starting to wonder about the Z Setting. I have is set at -.010mm

Newer Form 2 is running OK right now except for a bit of scum around the rafts. That’s as long as I space parts far apart. Means I have to do multiple prints to get an order done but better than spending time cleaning and filtering the resin.

JUST FOUND I have another issue. I print some delicate scale parts at 1:87 scale. One a Retro 2 Wheel Dolly is very fine structure but has successfully printed with ALW resin for years. This latest run is so brittle the pieces just disintegrate. Not sure what’s causing it and don’t want to start blaming the resin seeing I’ve been having so many issues with the printers.

Just ordered a liter of FormLabs Grey resin for express delivery. I need to prove if it’s the resin or not. This is a bit expensive test but I’m loosing more with all the clean ups, delays and reworks trying to solve this issue.

You know that the tank is a consumable, right? It wears out. The heatmap shows you how much wear has occurred on the tank. Always using ALW resin and having it always run well has nothing to do with heatmaps. No matter what resin you use, no matter how well it works, the resin tank will wear out and need to be replaced and the heatmap is how you determine that… so no matter what resin you use, there is a strong need for heatmaps.

With constantly replacing resin tray I don’t see how this is an issue. Also it’s never entered in for the over 5 years I’ve been running these printers.
I have a liter of FB resin due in tomorrow morning at 9. We’ll see how that runs as there’s a brand new tray in the machine.

Here’s a photo after I upgraded Preform and the Firmware of the printer. Also switched to a Formlabs resin tank so there is a heated resin tray. This is supposed to be O scale (1/48 scale) cart tires. It printed just two days ago OK but with a lot of scum. No stuck parts to the NEW resin tray but I think there is fine scum in the resin and it will need to be filtered.

Printers have had the Galvo mirror, main mirror and the glass cleaned 3 times and still scums.

Ready to throw all this equipment out the door.


FINALLY got a good clean print off the newer Form 2 printer. The .40mm supports held up during print but some parts fell of during the wash cycle. I can’t go much higher as my parts are so small.

I have a second job running on the older Form 2 using Open Mode and ALW resin. The Universal Tank is still out for delivery, maybe tomorrow.

And there a third job running on the newer Form 2 again but this and the one on the older printer are small and delicate. Pushing the limits but a standard products I had no issue printing in the past. Let you know how it all goes.

I did purchase a DIGI S-BOX printer this afternoon. It’s slated to replace the older Form 2 down the road once it’s up and running well. I’ll then sell that Form 2.