Bronson R. Hokuf wrote:
>
> Looking at Ec alone to determine the speed of a resin is a mistake. One
> must consider both the Ec and Dp. The exposure required to expose a
> layer is given by the formula:
>
> Energy = Ec * e ^ (Thickness / Dp) or
>
> E = Ec * e ^ (T / Dp),
>......
Looking at Ec and Dp is one point of "SPEED"!
Your discussion is typical theoretic. We all like values. But there are
a lot of factors which define the speed of an resin.
1. Ec and Dp
2. cure time ( how long to get a stabile layer)
3. time/shrinkage comparison
4. what exposure strategie do you need to get high quality part! what
quality do you want ?
5. surface tension !!!! Recoating delays ( nobody turns of the laser
while recoating)
.... and so on
My opinion: the only thing what´s real is the building time of a
benchmark part. Other lookings are just a academic point of view!
So if want to compare the speed of different resins you have to define a
benchmark part at all.
P.S. Three years ago ( I worked as an application engineer at EOS,
Germany) we sold a STEREOS 600SX because we build the userpart in less
than 4 hours with an RMS of 80 µm ( 150 mW ML-UV and SOMOS 3100). The
userpart was hot when we got it out of the machine. But I prefer the
SOMOS 6100 to 3100 because looking at all different steps from data
preparation to finish he 6100 resin is faster.
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