Build Your Own SLA/SLS

Are your cure times the same for red and green?

The green should be a bit faster than the red given the same cure time so will have a more complete cure. What are your current layer times for the red? With subsf you will have to overcompensate the normal layer time to get it past the base -> layer transition point. Have you tried editing your gcode to feather the base to layer transition time?

I think you are likely running too low of a cure time needed to get past the transition point. I'm not sure what causes this and it isn't unique to makerjuice. Even though the top of the print may be forming correctly the cure time will still need to go up.

Still getting erratic prints.

Tried bumping the exposure time from 3.5 seconds to 4.5 seconds; no joy. Then up to 5.5 seconds. Slightly better.

Went back down to 3.5 seconds, but increased the base layer count from 10 to 25. You can see the results. The first print was ALMOST perfect (see the little gap around the base). The second one dropped off of the build plate mid print (not shown). I tried printing 2 at once, but they are total crap. At this point, even the base layers are not printing reliably. I sanded the base plate again just before the dual print test.

Making little progress, although I am using up a lot of resin.

Is anyone making reliable, good prints with the LittleRP and Maker Juice SF? Could you explain your process in detail for me please?

I gotta say I'm really confused. I use MakerJuice resin all the time on my LittleRP and have zero problems....

Can anyone think of a series of simple experiments that I can perform that would allow me to eliminate some of the possible causes? I would have to perform 3-4 successful prints before I was convinced that the problem had been solved. Suggestions so far seem to include

- the projector is exposing unevenly; I need a Mask. Then why are some prints successful and why are the prints so erratic?
- the projector needs to warm up. I have done this, without an increase in print reliability
- I need to "feather" the exposures by editing the gCode. Again, why does it work sometimes.
- I have the exposure wrong (perhaps too low). Again, why does it work sometimes
- the resin is contaminated. Again, why the erratic results. But I can open a new bottle of resin. I could understand if the prints suddenly started being crap, but the quality seems variable. And I still cannot see how I would be contaminating the resin
- the resin is defective. Possible, but I think unlikely.

I'm wracking my brains to figure out what I could be doing in an erratic manner but not noticing.

Personally, I think your exposure time might be a shade low, but each printer is different.

The resin is "uniform" - no clumps, gel, non-uniform areas?

I have had some perfect prints at an exposure time of 3.5 seconds. I tried 4.5 seconds and 5.5 seconds, but that did not result in perfect prints. The same kinds of anomalies appeared

The resin is uniform when I pour it into the petri dish. Sometimes there are clumps when I pour it back into the bottle, but I have a sieve in place to catch that kind of thing

How much resin are you adding to the petri dish?
I've had similar problems with my printer (not a LittleRP) when I under-filled my resin vat. The surface tension of the resin caused it to pull to the build platform and left gaps/air bubbles in the resin on the bottom of the vat. Once the build platform was high enough, this stopped being a problem. This caused the bottom of my prints to fail in a similar way to yours but the top of the print managed to recover.

+1 to tom-res's post.

Thanks for the suggestion. I fill it 2/3 to 3/4 full...

Fresh bottle of resin, new build plate, new petri dish. The result? Better, but one defect. Sigh