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bolsoncerrado
02-29-2016, 10:10 AM
Ok i'm back from the probably longest weekend of my life (lol) after having to leave Morpheus OFF for the whole weekened haha

Quick question before I launch a long test print: the grid I see on the CreationWorks software.... is the FILM or the METAL grid on the Morpheus???

How do you set up the pieces in the software in order to get the result?

I missed that part on the tests of the nameplates since my name is so similar upside down lol

woale
02-29-2016, 11:13 AM
The grid shows the metal plate (=image is mirrored on the LCD), but I'm not sure if a specific setting was needed for this in CW.

bolsoncerrado
02-29-2016, 11:18 AM
OK so if I position Nefertiti with her base on the "grid" in a natural position, the printer will print it upside down, correct?

I should be ready to go then.

woale
02-29-2016, 11:19 AM
Yep, that's it

bolsoncerrado
03-01-2016, 06:55 PM
OK my first "serious" failed print has gone wrong twice.

First one was because of faulty USB ports on my laptop.

Now that I got a new laptop to work with, I did put too much exposure on it, which was giving me like 60h to complete a Nefertiti at 1:2 scale and 0.05micron! :(

This is what I just learned from another forum:

"The amount of exposure reduction when reducing Z layer height is not as straightforward as for XY. With XY, the concept is simple: same amount of light over a smaller area results in less time for the same “photon dose”. Thus, if you reduce the surface area (in cm^2), you reduce exposure time proportionally.

With Z, what happens is that you have less material to cure in each layer, but the photons need to get through some amount of photoinitiator and pigment to reach full depth. There’s likely some nonlinearity in this function, and since we don’t really know exactly how much and how absorbent these are, we can’t compute the overall reduction in dosage precisely.


A rough rule of thumb is to reduce exposure time by 25% for each halving of Z layer thickness. Thus is you were using 10 second exposures for 0.1mm Z, then use 7.5 second exposures for 0.05mm Z.


However, both resin type and any added pigments could change this."


I'll keep trying!

woale
03-01-2016, 08:01 PM
OK my first "serious" failed print has gone wrong twice.

First one was because of faulty USB ports on my laptop.

Now that I got a new laptop to work with, I did put too much exposure on it, which was giving me like 60h to complete a Nefertiti at 1:2 scale and 0.05micron! :(

How did the print fail with too much exposure? Any pics?



This is what I just learned from another forum:

"The amount of exposure reduction when reducing Z layer height is not as straightforward as for XY. With XY, the concept is simple: same amount of light over a smaller area results in less time for the same “photon dose”. Thus, if you reduce the surface area (in cm^2), you reduce exposure time proportionally.

With Z, what happens is that you have less material to cure in each layer, but the photons need to get through some amount of photoinitiator and pigment to reach full depth. There’s likely some nonlinearity in this function, and since we don’t really know exactly how much and how absorbent these are, we can’t compute the overall reduction in dosage precisely.


A rough rule of thumb is to reduce exposure time by 25% for each halving of Z layer thickness. Thus is you were using 10 second exposures for 0.1mm Z, then use 7.5 second exposures for 0.05mm Z.


However, both resin type and any added pigments could change this."


I'll keep trying!
I'm not sure if exposure time should be proportional to the XY surface area on the Morpheus... This only makes sense for laser based SLA printers.
For the Z layer thickness, TOW told me to keep the same exposure time regardless the layer thickness (25/50/100micron).

bolsoncerrado
03-02-2016, 03:15 PM
Well theoretically speaking, it makes somewhat sense: the thinner layer to cure, the lesser exposure required I guess...

There are actually two exposure times: Bottom exposure and Exposure time.

Have you all guessed what is what for each?

woale
03-02-2016, 04:33 PM
Well theoretically speaking, it makes somewhat sense: the thinner layer to cure, the lesser exposure required I guess...

There are actually two exposure times: Bottom exposure and Exposure time.

Have you all guessed what is what for each?
Bottom layers are "overcured" to be sure the part sticks to the metal plate. I think this is set for 5 layers. Then it continues with the normal exposure time for the rest remaining layers of the print.