My prints are coming in a whole size under what they should be

[KentaTakashi]

So after figuring out my problem with the homing cycle

I now have a new problem my ring prints are coming in a whole size under what they should be. I know this is a scale problem but I wonder where it is going wrong? The stl's I'm exporting are correct I've double checked. But an example is a ring size 7 is coming it a size 6.
Meaning somewhere in the setup there's something wrong with my scale does anyone have any experience or can help? Thanks

[mongerdesigns]

Most resins shrink. But a full size smaller is a bit much. Usually it’s recommended to make the rings half a size larger for printing. Check to make sure your grid is the correct size.

[rkundla]

Is that measurement before you cure it under UV or after? Do you do heat as well? Both methods will cause additional shrinkage as the resin cures.

[printcast]

If I want a size 8 ring, for instance it's drawn as a 8.25. printed, cured and cast. They usually come out a hair small but after cleaning and shaping they are right on or slight small. If needed I can stretch the ring a tad bit.
I would rather them be a tad small needing slight stretch than big needing to be cut down.

[KentaTakashi]

Yeah i'm accounting for shrinkrage but I've never heard of a full size shrinkage. I adjusted the projector grid to the default setting for 25 micron i forget it was 48x 27 or something like that but is that too small what are your experiences thanks for help

[Messerbr]

Every time after adjusting the grid I always print a 10x10x10 test cube, measure XYZ, plug in the numbers in the Scale Adjustment window, and reprint the test cube. That way I know everything should be 100% calibrated or really really close.

[KentaTakashi]

Every time after adjusting the grid I always print a 10x10x10 test cube, measure XYZ, plug in the numbers in the Scale Adjustment window, and reprint the test cube. That way I know everything should be 100% calibrated or really really close.

ideally when i print hte test cube what should i be inputting in the scale adjustment window in solus contour? the measurements of the cube?

thanks for the help

[Messerbr]

Every time after adjusting the grid I always print a 10x10x10 test cube, measure XYZ, plug in the numbers in the Scale Adjustment window, and reprint the test cube. That way I know everything should be 100% calibrated or really really close.

ideally when i print hte test cube what should i be inputting in the scale adjustment window in solus contour? the measurements of the cube?

thanks for the help

For the initial cube have everything set to 10. Then print your cube and measure the X and Y. Input those numbers in the corresponding "Actual Scale" slots. Print the cube again and Contour will adjust the scale so that the new cube will be 10x10x10 or really really close.

After resetting my grid the last time my actual size for the X and Y ended up being 9.7 so I input those numbers in that slot and now my scaling is accurate.

When printing directly to the build plate your Z may be a bit smaller due to the increased exposure of the lower layers. Don't worry about changing the Z number. by the time it gets to the main ring layers the Z scaling will be correct.

[KentaTakashi]

Messerbr Thanks for the help that was really informative. Hopefully this resolves the problem

On that note I also have some other problems to contend with. My first couple of prints were actually good just undersized. I haven't done any scale adjustment yet but other test prints i've been doing have been either getting destroyed or warping. Namely the cube.

https://imgur.com/N4iO3QS

when i first tried to print the cube it just stop and sheared. didn't keep printing even though the slices seem to be fine.

https://imgur.com/R7AT1zQ

further attempts saw me rotating and supporting the corners of the cube so that it printed hanging but it warped the cube. I don't really understand what went wrong here.

https://imgur.com/UnwCw3B

we then tried printing pendants to see what was wrong and it came out but the bottom portion as you can see has really weird degredation in slices after a certain point.

https://imgur.com/UQWNcRk

more recent attempts of the same pendant saw the part where it begins to degrade not even being printed we looked in the tank for floaters but didn't find anything.

https://imgur.com/8f3yis0
https://imgur.com/pyYWpJf

most recent attempt the broken off one is the pendant didn't even form the cube is still warping and while the ring came out it seems the measurements bow out wider in the middle for no apparent reason.

Any insight can help Thanks for everything so far guys

[Shinlocke]

For the cube, it looks like it is at a 45-degree angle, with the edge of the cube being horizontal with build plate (so it looks like a V). I would not recommend that. You are still building layers on layers, your support is along that ridge but at the v, making the connection weak. You probably want something less sharp, like 20-30 degrees. Then your support can fully go on the flat part, not the V-edge but still support that side, giving a more stable and stronger surface to build the rest of the cube on top of.

I'm assuming you did auto-supports? For the other stuff, you'll want to be in "Support" mode and go through layer by layer by looking under the model. You'll want to look for any islands or points that slice but aren't attached to another part of the model. Auto-support doesn't 100% of the time get each place a support needs to be. You might find some parts that are identified with 'green' needing supports, but not actually supported and you might some areas that don't show up but end up being an island. Auto-supports does it correct about 95% of the time but it still can miss spots which require you to spot check and manually add where needed.

At least that is my experience so far... I'm still a n00b.