Also, im surprised you used 25 setting, since previously you said the mix was optimized for 50 mic… did you get noticeable improvements going from 50 to 25?
With the new mix I notice the surface is a little smoother at the 25 setting and some details are sharper. There was almost no difference using the 50/50 mix though.
Here is a picture of the model. Keep in mind that the photos I posted above are macro shots (with stacking and really up close), so you can see every single detail and the grow lines may be exaggerated by the lighting and shadows. In person the print looks a lot smoother, you cannot see or feel any of the grow lines and the overall print is much better than in the photos.
I meant… there is not a lot of difference between the 25 setting and 50 setting using the 50/50 mix. But there is a noticeable difference between the 2 settings using the 75/25 mix. Just to clear it up. 
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I’m learning how to stack photosensitive resin and photos : )
Has anybody else using the mix noticed a dimensional accuracy difference compared to straight resin? I have a limited sample size, but the parts I printed in 50/50 B9Cherry/FormLabsWhite seem to be consistently undersized by ~.002" per surface. My guess is that the effectively smaller spot size of the laser in the more densely pigmented resin means that it doesn’t cook the full region that PreForm thinks it will. But I’d be interested in others’ experience on measurable features. For example, I’d guess that the ring on Monger’s shark tooth would be oversize for ID, undersize for OD, and undersize for thickness.
Hi Tad,
I think you are right. Because the resin will cure “tighter” the accuracy may vary a little. The form1 is calibrated for it’s own resin. Since the mix cures with higher detail, in effect everything is shrunk down a bit. Of course it would very easy to compensate for this by measuring the output and scaling up the model a little in preform. Most my models don’t have such strict dimensional requirements, so it’s not an issue for me.
Hey Monger,
What do you think of the Kevvox?
What’s the best printer out there for under $25k for heavy production of castable patterns?
Taking into consideration the following, in order of importance:
1- Print quality / surface finish
2- Easy castability
3- Speed
4- Build Area
Haven’t seen one in person because they have no presence here in the USA.
But it looks promising. For that much money I would want them to print a sample of my choosing for me, so I can cast it and see what they promise is true. So far no one has contacted me from the company after I sent them a request for a sample.
Im in touch with one of their salespersons. Sending them files today. Will let you know how it goes.
I’ve seen some of those. It’s a really nice printer, but is it 25K nice? I just don’t know. Those rings still have lots of grow lines on them that would require some work to be cleaned. If you are making a master and then a mold, it’s not a problem. If you are making a production of 100 rings, it could be a problem. I don’t think tumbling alone will get rid of those lines.
I think it is the build volume and cost of the resin which puts me off the Kevvox. $700+/liter…come on!
For me the problem is still that at that price, I expect something that outputs close to perfect quality prints. You can at least get that with Envisiontec or even the new solidscape z studio wax printer.
Thanks for the pics Jesse, they look really good, but as monger says, I can still see build lines.
Monger - does that mean for the same money you would go for the envisiontec over the kevvox? Their pics look nice on their site, but then again, so does everyone elses. And what about all the problems casting their resin… isint Kevvox claiming theirs is easier to cast?
Solidscape is out of the question because of speed.
I just asked for a quote from envisiontec. They seem to have many different models, and each seems to be customizable with different lenses, etc.
The envisiontec rep that I keep seeing at the conferences is never helpful…
The only reason I wouldn’t get an et machine is because of their shady business practices. Charging too much for resins, support contacts, etc. But the quality of the prints is top notch.
I agree, I dont have a good feeling about them.
Hey Monger, You had said before that you can vulcanize the b9/form grey hybrid resin. Can you confirm that?
Jesse,
The 50/50 mix worked great, but 25/75 mix got stuck to the mold resin a little. On another note, I was able to cast the shark tooth directly from the 75/25 mix print 
The ring and the cross didn’t work very well though.
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In both those instances that’s 25% grey and 75% b9 just to clarify.
Thanks for clarifying that MD, I think it’s time to commit to some cherry, your results are really nice and congrats on getting a casting out of the 25/75.