
1) PDMS. This abbr. stands for polydimethylsiloxane. Basically it's a Silicone found in every household. Yes, it is really as simple as it sounds. As of now I think that EVERY imaginable silicone should work to some degree, of course if it is clear and plainly flat. Some will do it worse than others, but they will work. Maybe some variants will work even better while being cheaper. Sylgard is best in it's clearness and UV resistance. Others can be more foggy from the beginning, and may break faster, but in the other hand they will be cheaper.
I'm experimenting around one month with some locally available PDMS. It is more foggy than ordinary Sylgard and because of that cure times for every layer, for every material should be twice as high. Yes, twice! And still it looks fairly clear to look thru. That is really strange. But on the other hand it is more hydrophobic than Sylgard and cleans in the matter of minutes like the teflon fry pan - just tilt it and all of the contents will easily flow out waAAAy more faster than off the Sylgard. But really the main advantage is the price. It is... 6-7 times cheaper than Sylgard here! Yes! 6-7 times!
Also I ordered 3 more different materials. Two of them are based on PDMS, and third is something based on the polyurethane. Also I still got some untouched teflon films thanks for wich goes to Josh - he is really helping guy

So the bottom line of that paragraph - don't waste your time sitting there and thinking. Just go and do it! Try some different materials, try some combinations of that materials, try something at least! Don't be scared to experiment! But of course have some common sense on it :)
2) Cleaning. I really don't getting why everybody are so concerned about that paragraph. Trying to find some other VAT materials (like aluminum and glass) just to return to alcohol cleaning, experimenting with detergents and so on. Hey guys, just answer yourself to one simple question - are you going to show off your printer to some nationwide TV channels tomorrow or you will bring it to big show/fair/exhibition?! Why to pour the resin back into bottle thru the stirrer every time the print is finished? Why to clean the VAT, build table and sweeper every time? Why to dry it after? Why to contaminate the surrounding neighbourhood with such a chemicals at least?

Just the plain numbers: I stopped to clean my second VAT as an experiment. It was mid august. I'm printing on it still.
I really stopped to count prints after 25th, but now looks like it is more than 40 prints on it. And still the 100XY part looks very-very good, with only 50XY already fading to almost unusable foggines. It had never seen water, alcohol or paper towels. Also I'm not cleaning my sweeper - just wiping it slightly with paper towels sometimes. And sometimes not.


But the main hint here is to tilt the VAT after print so that window area will be exposed to the air and will breathe. I'm using it's own screws placed underneath it for that. Guess the best place to leave the VAT with the resin in it? Yes! The printer itself!

But of course if you had bad print before that you should stir the resin.
Bottom line for TLDR'ers: don't clean your VAT. Just tilt it (to expose window for breathing) and leave it till the next print. The same for the build table and sweeper.
3) Pigments. My favorite part as you probably already know



As to pigments, you can use any, even dry ones, but remember few simple rules - size of particles should be small. Smaller - better. 1-5 microns works nice. 10-15 I guess is the limit. I tried the ones with 15-50 microns and that was bad. Also they should not react in any way with the resin and don't change it's chemical properties. For example I tried the titanium dioxide and looks like it made something to resin - it began to shrink waay more than usually. And also when it settled the resin color was red. Not yellow or yellowish green as usual. Right now I'm experimenting with fluorescent pigments. Still have to figure out if this is better than ordinary or it is worse. My guess here is that they will overcure the resin slightly more as they are re-emitting some ligh. Also it is really easy to work with them - they are very small, around 3-4 microns, they are cheap and extremely easy to mix. But I still have to figure out how they influence on the casting.
Bottom line: the more pigments - the better quality, BUT you should know how to handle them. It requires some practice.
4) Different resins. My thought here - everything that will cure under UV will work to some degree. Will it be better or will it be worse only experiments will show. Also it depends on what features you are expecting. But in one I'm really sure - photoinitiated resins is so wide field that almost every imaginable features can be implemented if there will be demand. And in observable feature it will be the case! You saw how many resin printers popped up in the last time?
As an example, I took some resin used for making stamps (Looking at that in retrospective I understand that this was my first question that I asked here about it. And almost year after I answering it by myself. What an irony?


Another words - if you see something on the horizon, which CAN work probably - stop thinking, grab it and try it! :)
5) Ultrasonic cleaner. One of my clients recommended that. He said that all of "professional grade" companies always do cleaning of the models in such a way. Firstly I thought that it is something extremely expensive to try. But how surprised I was when found that it can cost less than $50! Of course grabbed one and what? Well, it is really cleaning slightly better than just rinsing it with alcohol. But the main advantage which I found is that alcohol stopped to smell all over my home. Now it stores all the time in the ultrasonic cleaner and when I see that it is too dirty I just pour it out in one move. No more rinsing and overnight smells (my bedroom located near bathroom, so after I cleaned the models I was able to smell that awful odor all thru the night). Also as a bonus - it lowers the usage of alcohol. You will really need no more than a simpler model. The main rule is obvious - it should be able to accommodate all of the possible you models. Mine is 0.5 liters, 130x80 mm with around 50-60 mm in height. All of my models, even 100XY nicely fits into it.
And Yes, I'm using pure 99,92% isopropyl alcohol in there. I know that it is kinda dangerous, but still (around one month) everything was fine.
Bottom line. If you are serious about B9Creator or some other resin 3D-printer - you should buy one.
6) Breathe time and print height. I started to doubt that big breathe times will help to save the PDMS. Can't explain it though. Just a guess. But what I really certain off is that small height prints are definitely saving PDMS. I was able to do more than 20 short prints with only 30-60 minutes of breathing pause between them. PDMS looked almost pristine after that. And on the other hand I destroyed fresh PDMS with only one 132mm height print.
Bottom line - shorten your prints to most possible degree. That will save your PDMS a lot!
7) Sweeper mod. My brother implemented my idea of more civilized way to use Rabs1 (http://www.b9c.com/support/?mingleforumaction=viewtopic&t=744) Sweeper mod. It is really simple but effective. Also as to me it is easier to find a replacement rubber strip from the car windshield then to order it from USA.
Already modelled with a 0.3 mm base. SketchUp sources are included. There is no photos but you will immediately get clue of what it is and how to use it.
Here is the file:
http://www.thingiverse.com/thing:168550
8) Full HD. Yes. Me too. LOL

Already found the most possible candidate among all others. Contacted Vivitek to weed out outdated models from the 3-4 candidates, so it will be easier to work with it. You know it becomes troublesome to find parts or replacement for outdated models. The 950HD and 952HD (which a lot of people considered as a main variant) will be dropped off next month or so, so if anybody wanted to do the trick with em - it's not the best ones. Also the same to the H1080. Only one which is fairly cheap and introduced in this summer (lifespan of the model should be not less than few years) is H1180HD. It has pretty powerful optics which should give us more room for modifications I guess. On the other hand it has only 190 watt bulb, so that gives us around 25% less light penetrating the surface of the build area. Well... I think it's not a big deal though. Also I hope that it's optics is as easily modifiable as in ours D535.
So only time will show how easy it was.
9) Workflow. If anybody interested as of now my workflow for the post processing is as follows - print the model. Raise the build table up. Take it and scrape the model off. Then I usually put it back in place (yes, without cleaning). Put the model into ultrasound bath. Leave it there for 10-15 minutes. Take that time to tilt the VAT and clean if something was spilled. Take model out of the cleaner. Dry it with hair drier or air compressor (or just shake it off and blow with your mouth). Put it in the UV oven (also small improvement here - i changed the lamps from mild UV (stock) to deep UV. They are looking like really "black light", not like ours current - light blue. They cure resin slightly faster) for a long time. Usually around hour, or two. And that's it.
10) Photos. Sorry, but nothing extraordinary spectacular and new here. Only trying to earn a living with all I learned so far. Got a lot of customers works photos, but don't have time to scrape all of them to site or even sort them out. Some of them can be seen on my site thought. Here: http://y3d.com.ua/galery/ and here: http://y3d.com.ua/2013/fresh-photos-casting-of-3d-printed-models/
But wait... I want to share my new animal sentinel character nonetheless. I can recall someone asked about him sometime before, CarterTG can you remember?


P.S. Well, I see that I failed. I failed to make it short. Sorry :)