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Discussion Starter #21
The design looks okay but a few things... what fans are you using for the airflow on the sides? The sides need ample airflow. The more fans you have, the more uniform your laminar air column will be. A little filtering on the top of your straws would help too. Fiberglass air conditioner filter works well and is very inexpensive.

The next thing... the 1" pipe is too small. I would use a 2" or even better, a 3" diameter pipe with 3/8" holes about one per inch. You want air flow... more air, slower air. A 1" pipe will require a lot of pressure resulting in higher velocity air which hurts laminar airflow. Slower/higher volume is always better.

The last thing I see is that you have separated your fog section by a bit. If you look at the fogscreen that I built in this thread and the fogscreen I built in my first thread, you will see that the honeycomb is the full volume of the bottom of the fogscreen. On the first fogscreen, the center (fog) scection is separated, but only by very thin sheets of metal. This keeps the fog layer and the protective air layers very close. The fogscreen in this tread, the fog is separate only by a single layer of straws that run inside the fogscreen and connect to the honeycomb. Your design should work but it probably won't be as clean.

Please don't get discouraged by all of this. Your design is good and should work when you get the kinks ironed out. Laminar airflow is not easy and takes some trial and error but you're definitely on the right track.

As far as the projector, 3000lm should be more than enough light *BUT* it depends very heavily if your projecting onto the fog or projecting through. If you are projecting onto the surface of the fog (like you would if you were using a regular white screen or a white wall) the image will be VERY dim. If you project from behind the fog and project "through" it, your image will be much brighter and way cleaner.
 
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Thanks a lot bro, because many discouraged me, but I was very much impressed by your work, so I'll make changes and soon show the good results and I am going to add interactive videos to this sector, using motion sensors, pls guide me in my further post also bro... But really said your fog screen is very great, really I can feel your hard work in it, while I am doing mine, really your work is great bro..
 

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Discussion Starter #24
A 3/8" Cell diameter would be the limit, I think. I wouldn't go any larger than that. I even see a difference in laminar quality between the 3/8" and the 1/4" used in my old fogscreen. Even still, I wouldn't use smaller than 3/8" either mainly because of the condensation. My old fogscreen suffered greatly from condensation buildup. As the moisture collected in the straws, the water formed a meniscus and blocked fog flow almost entirely. On my new fogscreen here, the 3/8" cells seem to stop water from blocking the fog. So, it looks like 3/8" is the sweet spot.

For the honeycomb, I bought from https://aluminum-honeycomb.com/site/. Be warned, this stuff is a PITA to cut, expand, and cleave. If you're up to the task, you can get a stock "sheet" and do it yourself. For a higher price, they will also expand and cut the honeycomb to your specifications. Shipping isn't cheap though.

In regards to your PM to me, here is a *VERY* crude cutaway drawing of the fogscreen and the airflow paths:

View attachment 549514
 

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Just seeing this and i am sorry I did no see this sooner. What a great job you did making this and so very professional looking. I am sure it is a hit with everyone that sees it in action.
 

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Discussion Starter #26
Just seeing this and i am sorry i did no see this sooner. What a great job you did making this and so very professional looking. I am sure it is a hit with everyone that sees it in action.
Thank you! It's been a fun and frustrating build!
 

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A 3/8" Cell diameter would be the limit, I think. I wouldn't go any larger than that. I even see a difference in laminar quality between the 3/8" and the 1/4" used in my old fogscreen. Even still, I wouldn't use smaller than 3/8" either mainly because of the condensation. My old fogscreen suffered greatly from condensation buildup. As the moisture collected in the straws, the water formed a meniscus and blocked fog flow almost entirely. On my new fogscreen here, the 3/8" cells seem to stop water from blocking the fog. So, it looks like 3/8" is the sweet spot.

For the honeycomb, I bought from https://aluminum-honeycomb.com/site/. Be warned, this stuff is a PITA to cut, expand, and cleave. If you're up to the task, you can get a stock "sheet" and do it yourself. For a higher price, they will also expand and cut the honeycomb to your specifications. Shipping isn't cheap though.

In regards to your PM to me, here is a *VERY* crude cutaway drawing of the fogscreen and the airflow paths:

View attachment 549514
Thanks again I really appreciate learning from you, that really helps me understand the science behind this wonderful build. I would love to see the mods sticky this thread, this is really next level type stuff.
 

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Discussion Starter #30
Just dropping in to say "HOLY FREAKIN' COW" like everyone else. This is just incredible.
Thanks! I really appreciate the props, guys. Unfortunately, the kids in my neighborhood have slimmed down a bit due to most of the kids have moved out and not a lot of new families have moved in. It is definitely an "older" neighborhood. Still, the kids that do come around genuinely seem to like the effort I put into the haunt as well as the fogscreen. It's also nice to get some nods from fellow haunters from this forum. So to all, thank you again for taking notice.

On a side note, I have more stuff to post but my later pics in this thread are not showing up. Is there a size limit I missed somewhere in a sticky thread???
 

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Discussion Starter #32
Hoping this will let me post more pics without them being "invalid attachments". There are a few pics in this thread that are just not showing up. Oh well.

Here are a few more shots of the finishing touches added to make this less of a mess and more user friendly when it comes to setup/tear-down.

Fogger PSUs, Triac relay, and control box mounted to aluminum rails
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Laser etching/prepping and mounting anodized plates for the various connections
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Finally painted and finished (for the most part). I still have more "cosmetic" things to add but this project can now be written off as "complete". But realistically, we're all Halloweeners, when is anything every "Complete"????? :p
forscgreen8.jpg
 

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Hello absolom7691, your work of DIY fog screen is really amazing. I wonder how you had done with the filter to prevent the water mist emitting from the ultrasonic mist module becoming water drops?!! Could you give me a full instruction with sketchup files of how to make the fog screen II and its controller with DMX completely? Thanks so much
 

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Discussion Starter #34
Hello absolom7691, your work of DIY fog screen is really amazing. I wonder how you had done with the filter to prevent the water mist emitting from the ultrasonic mist module becoming water drops?!! Could you give me a full instruction with sketchup files of how to make the fog screen II and its controller with DMX completely? Thanks so much
I apologize but putting together full instructions would take a great deal of personal time so I won't. I will also not give out construction files or schematics. I will happily assist anyone who is getting their project going or is already building one of these and is getting stuck. As most people are aware, there is a large amount of scraping on these awesome DYI forums like this enabling foreign companies to steal user's ideas and profit by them. That being said, I am leery of first time posters asking for a complete break down of my project.

I have had many people ask me about this project who are getting ready to work on theirs or are already working on one and I have had no problem sharing information with them. None of them have asked me for what you're asking. So again, I apologize if this is not the case. Too many times I have been asked, on here, on youtube, and a on laser forum, if I would kindly provide plans, files, schematics, detailed instructions, even full parts list (down to hardware!), and list of vendors. It's data/project scraping and I will not contribute.

To anyone else on here, please ask away if you need advice or help if you're building a Fogscreen. I will be happy to help! I am normally pretty good at ascertaining between the genuine people and those looking for info to profit by!
 

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Hello absolom7691, thanks for your patience with me.
I have a question. Currently, i have problems with water dripping and leaking along the area of where the mist coming out!
Could you take pictures of your water mist draining system of your fog screen to prevent leaking and dripping problems? Thanks and have a good day!
 

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hello

i've tried to make a fogscreen for about 2 years and i've spend about 2000$ but i've could not make one of them. my main problem is making a laminar flow of fog and it starts to turbulent after a short distance it comes down.

would you help me please?
 

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Discussion Starter #38
hello

i've tried to make a fogscreen for about 2 years and i've spend about 2000$ but i've could not make one of them. my main problem is making a laminar flow of fog and it starts to turbulent after a short distance it comes down.

would you help me please?
Sorry for the delay, I only go on here about once a week. Do you have any pictures of your setup? What kind of fans are you using? There are a couple of things I would need to know about your setup before I could accurately help you.
 

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Ur welcome. I wish I could make a conversation with u in other ways, like email, whatsapp, instagram or any oher instant messengers.

Anyway… of course I have pictures which I'll try to send here if it’s possible at all.

I’m using MISHINA FAN model SB12038HA2 and other things that i will explain:

i used a 33*20cm tank which 4 ultrasonic foggers (that they are handmade) are on bottom of it and two fans which i mentioned are mounted on two sides of this tank for leading the fog to get out from the Longitudinal groove which i created on other sides of tanks.

this tank is a separable part that i take it out everytime which i wanna fill water.

there is no problem yet. i have so soft and enough fog that i lead it to the part which is seperated from air channel and there are one row of straws (the red straws from the bottom vision is clear in picture) that the fog goes into these and make the curtain for projecting the video on it.

the air channel is on the two sides of the fog flow to sandwich the fog but i think it doesn't work well.

the size of the whole device is about 50length*30width*60Height centimeters
(i've made the last fogscreen in small size because of the prices and money which i've spent till now)

the big problem which i've had in all these 5 devices that i made and i've changed sth in each one, is the laminar flow.

i control the speed of all fans by a dimmer and all of them are connected to a MeanWell PSUs.

my problem is only making a laminar fog flow.

i read ur thread word by word and i know there are differences between my fogscreen and urs, e.g DMX controller, aluminum honeycomb, fluorescent diffuser plastic, Fiberglass A/C filter, window screen, etc. but what should i do to make the fogscreen as formable as urs and the fog doesn’t fill the room?
do i have any way to make a laminar flow in this device or not?

excuse me if i couldn't explain as well as u but i did my best.


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Discussion Starter #40
Please correct me if I am wrong but in your pictures, it looks like fog "layer" is laminar but the shielding air is not. From what I can see, the fog is moving through tubes, or straws and the surrounding air is not. The whole air column needs to be laminar. The fog layer as well as the surrounding shield air. If the surrounding air is not laminar, the fog layer will break down very quickly. Please forgive me is this is not the case. Whatever your method of honeycomb (straws, tubes, aluminum honeycomb), your fog layer and air layer should be moving through the same honeycomb configuration, same size (height and diameter) cells and the air speed for both should be exactly the same.

I don't know have fast your airflow is but lower speed, higher volume always works best.

The other thing I notice is that there is space in between your apertures. The closer together they are, the better. The further apart they are, the higher the reynolds number and the quicker the laminar flow breaks down. They is why honeycomb is preferred over a grid pattern for circular laminar filters.
 
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