I’m having problems with variation in the surface quality of the print. On the side closest to the platform, the print quality is very very poor with many of the details of the features lost in a mush. The side that is further away from the platform is printing with a good qualityThis does not change no matter how many different ways I try to wash the parts to remove the resin.
The orientation of part on platform is like this. You also see a variation along the same surface as shown in the picture below. It isn’t as drastic as the difference between the side facing out and side facing in but there is still a very discernible change.
Can you still raise the height above base? I had a similar result on prints and raising it from 5 to 10 worked for me. It must have something to do with the resin flow.
There is still room to raise it and I will do so for the next print for this.
However, I don’t think I made myself entirely clear, Using the graphic above but with more accurate labeling we have the graphic below. This kind of a trend with parts suffering from the quality of print on the topside versus the platform side no matter the orientation is always true. The side that faces the platform will be kind of “mushy” in quality to the point where you can’t see the lines from the layers even in the coarsest print setting whereas the side that faces away from the platform is usually going to be of good quality.
I have the same issue. Interested to see if anyone has a fix. I assumed it was from uncured resin sitting on the top of the model but have not figured out how to solve it yet.
@Will_Hilgenberg Most of the time I print in clear and white so I have no long term experience with the black resin. I noticed that my black models came out worse than my other prints in lighter colour though. To be sure I would need to print more in black resin but if you print on the highest resolution and in black too, the laserpower is at the highest level I guess. So in case your printer is not perfectly calibrated I wonder how a print in black resin would come out with the preform setting of GREY resin! I print my pigmented clear resin at the black setting and it works great. Keep in mind that the colour settings obviously changing the laser intensity like more power and/or longer curing. Another problem might be that the higher the resolution is, the more any tiniest dust particles effect the print even more. Thats why I often got cleaner prints with lower resolution prints!
I had silimilar issues with a model, new tank, new resin. what I missed was to stir the black resin long enough. I assume by not stirring it throughoutly the pigments get clogged. Also on the poor quality area I see a more dense support structure, maybe the resin can’t flow good enough there? just my 5 cent
I had the same problem.
The top side have a very good quality, but the bottom side is every time bad.
My Form1 (without+) is now quite well calibrated.
Possibly the resin running off the base onto the bottom/supports touching area of print and curing when the laser passes through. A bit of a disadvantage with the upside down SLA printing.
@Will_Hilgenberg I think @MarcusKnorr and @Edward_Peretti explain it pretty well in this post and you should try to raise the object from the buildplatform, if thats possible though…
For the sprocket above I would try printing closer to vertical. The more horizontal the part is the worse this effect will be. It would help if we look at all of the factors that can effect the top side and work from there. I’ve seen worse than above on my machine but I’ve also seen better.
I can think of five or six things that could be contributors maybe I’ll take some time to investigate a few things.
Used resin does seem to make things worse but it’s not the whole problem. This can happen with new tanks and new resin. It’s worse with a vat that has had several prints in the same resin (even after it’s filtered).
I will be giving it a shot a little more vertical to figure it out but this happens with nearly all the parts that I print.
I’ve been using a new bottle of resin for the prints and have mixed thoroughly prior to printing.
I will be reprinting the part with 10mm off of the base instead of 5mm and with the number of supports on the lower backside reduced in order to improve resin flow. We shall see if this alleviates some of the problem.
My current running theory is that the laser light is bleeding through when printing. This would be in line with the improvement int he quality when printing at 0.1mm resolution instead of 0.05 or 0.025mm.
Was the improvement good enough for what you are trying to achieve? Good enough for some fine tuning after the print?
For the delamination (layer peeling) look at the printed part and add manual supports to stabilize those areas. Remember as you get close to vertical it’s important to support not just the pulling force but to add supports to keep the part from rocking side to side.
You can change the point size of the manual points to be different from the auto generated ones. This way you can use the smallest point size to just stabilize the part.
The laser energy is curing the resin to a greater depth than the layer depth as there is nothing cured behind, you describe it as ‘bleed’ if your bottle of resin has been stood for any length of time particulates settle and some like to stick to the bottom of the bottle.
Ever noticed with grey resin in the build tank you can see the particulates seemingly sinking and sticking as a whitish layer to the top of the silicone release layer (V1 anyway).
These particulates are incredibly fine and I’m not sure of there function but they may act as fillers and cure depth limiters?
So if these have stuck to the bottom of your bottle just shaking it will not get it all back into suspension and mixing in the build tank fruitless.
I put a stainless steel M6 nut (cleaned in IPA and dried) into my bottles before shaking to thoroughly mix, any weighty inert non sharp object should do it.
@Fred_Baumgartner
The print quality was where I need it to be for the top surface but the bottom surface was still of dismal quality.
The delamination absolutely can be solved through the addition of support points and I just got a little excited when removing supports.
For the size of the points, I’ve played around with them in the past with minimal impact except removal. Now I always run them as small as possible.
@Marc_Collinson
This is something else I have been wondering about as well. Actually making the change from grey to black resin did improve the overall quality of the print a bit. I would assume due to it’s ability to block light from bleeding through as you hypothesize. I’ll give the nut trick a try when I get a new bottle of resin.
I am continuing this experiment by trying different parts with the same changes to see how it works out. We shall see how it goes. . .
