Fogscreen Project

[Lazerjock]

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Keep up the good work. I love this kind of stuff.

[absolom7691]

Well, I made breakthrough progress today. I finally got my fog delivery method worked out (for the most part). It is not the cleanest but it works. I may improve it in the future. I knocked everything together for a test run to see how it performed before I wire everyting up proper and paint it.

For the test, I have the fog blowing from the ground-up only because I don't have an overhead mounting solution yet as this thing weighs about 130~150 lbs. The results may be even better when the fog blows downward because of the evaporative cooling effect of the fog and the changes in the air density.

The fog density it just about perfect. It is thin enough to see through but just opaque enough to refract and disturb projected photons. I haven't tested my laser projector it yet because my garage is a disaster (as you can see in the pics) and I need to do some spring cleaning and get everything set up. I am hoping to get some projections on it tomorrow. My goal is to get this to look like Noseeum netting but able turn it off when projecting beams. For halloween, I will be using a video projector with scary images or video that the kids will pass through on their way up to the porch for some treats. I am uploading video to youtube right now.

Please excuse the messy disaster that is my garage. When I get working on big projects, I let stuff go

[jammah]

Ok WOW that is brilliant! I love it, screw scrim, one of these in front of the dj at my regular club rigged to dmx or even a on off switch next to my controls = the ability to blast a screen for bursts mid show very cool mate well done
really looking forward to youtube clips
james

quick question, what are the necessary specs for the ultrasonic foggers?

[absolom7691]

Ok WOW that is brilliant! I love it, screw scrim, one of these in front of the dj at my regular club rigged to dmx or even a on off switch next to my controls = the ability to blast a screen for bursts mid show very cool mate well done
really looking forward to youtube clips
james

Thanks!

Here's a brief video of it running. There is still more to be done but the hardest parts are finished.

[absolom7691]

So, I couldn't wait. I cleaned up a little space and set it up again. Even with the lights on, the projection showed up very well. One thing to bear in mind, because my projector was only about 4 feet away, I had to increase the scan angel which gave the image an extruded look. If the projector were about 20 feet away, the letters would be much clearer.



- - - Updated - - -

Once more with the lights off.

[planters]

Wow! I was only loosely following this project and then I saw your most recent post and went back through the thread from the beginning. Fantastic. How high above the box can you still get a decent screen effect?

[jammah]

That is very effective! If you dont mind sharing What did the ultrasonic foggers end up costing? Ive been hunting online for the last few hours they really vary heaps in price
Very cool stuff!

[Lazerjock]

Amazing!!! Great job.

[JasonB]

Great work, the projection looks great. Got a kick out of your comment about winding a Tesla Coil Secondary (been there, done that!). Information Unlimited's BTC4 [anyone remember that outfit?]

"There is no feeling that goes through the human heart as that of an experimenter when he sees his ideas come to reality" -Nikola Tesla

And thanks for sharing the links that got you started on this project. I work for a company that used to sell air knives (competed with Exair) and can say with experience that a lot of the development and testing is simply trial and error .... Somewhat of a black science , although there are formulas as stated by Anon on finkbuilt.com ...

I'm the same way when I get into projects, the room becomes a disaster area - Now get that work area cleaned up before you trip on something and hurt yourself (Or worse, the fogscreen!)

-Jason

[absolom7691]

Thanks for the kudos, guys. For me, this project was mainly a proof of concept: Could an effective fogscreen be built? Now that I know it can be, if I were to build a second one, I would be willing to spend more to get better results. I love/hate building things out of wood. Love: It is easy to work with and generally cheap. Hate: Finished product is heavy and unstable. The straws were also used based on price. Each straw is slightly different though. Shape, straightness, opening at each end... this all affects the laminar flow and adds turbulance.

If I were to do it again, I would use a professionally made laminar matrix for it's uniformity and also practicality, timewise. Try looking laminar honeycomb up on Google! I only found a very small handful of companies and most sell only to large businesses. I found a company based locally that manufactures and sells to anyone http://www.plascore.com/pc2-polycarbonate-honeycomb.php . To be fair to them, I won't give the quoted price for the dimensions, it was not cheap but would probably balance out if I were to factor in the man hours in labor I spent laying down the straws.

Wow! I was only loosely following this project and then I saw your most recent post and went back through the thread from the beginning. Fantastic. How high above the box can you still get a decent screen effect?

Thanks! That means a lot coming from you. I have seen your projects and your fabrication capabilities! I think I can get a good 48" ~ 62" with decent results though it is hard to tell with my hasty setup. Since my projector was so close, my scan angle was huge and affected the clarity of the image. I am going to test more thoroughly when I get it dialed in.

This is mainly designed to blow the fog toward the floor and I am not sure if it affects the laminar flow since the fog does have mass and wants to fall. Also, as it evaporates, it cools the air, making the fog layer heavier. I'm not sure if either of those factors are enough to disturb the flow by blowing it upward. I am looking at getting some lighting truss to mount this to. It may give me a more stable screen further away from the unit.

If you dont mind sharing What did the ultrasonic foggers end up costing?

http://www.oceanmistmaker.com/humidifierwholesales.html seems to be the only place to get a good price when buying more than one but less than 30. I saved a bundle on shipping since they are local and I will-called the units. These foggers draw about 200W each and since the resonant fq of the transducers is in the MHz range, the PSUs are iron since switching PSUs are noisy. Shipping for these is expensive because of how heavy they are. I paid less than $400 for all 4.

Amazing!!! Great job.

Thanks!

Great work, the projection looks great. Got a kick out of your comment about winding a Tesla Coil Secondary (been there, done that!). Information Unlimited's BTC4 [anyone remember that outfit?]

Thank you!

I bought my tungsten electrodes from them. My coil was also homebuilt but sadly, perished after going through several moves. I am looking to build another one in the future.

Here are some pics of "Chimera" before she was destroyed


After raising the topload due to high incidents of strike rail hits