Help! Smoke Generator(Powder) for RC electric planes

[cdfigueredo]

I am worried that for air collected from plane forwards movement and propeller wash that the restrictions to the openings in this model will be too harsh.

I do think the shroud assembly looks markedly improved as compared to the last version. How do you keep the top and bottom halves of the shroud connected?

More than anything this prototype is to let my imagination run wild and conceptualize something improved based on the previous concept, I'm not 100% sure if it will work or if it will be more or less effective than the previous one, but I enjoy the process of conceptualizing.

The upper cover will be inserted into the pylon and screwed from below, and the lower cover will also be used to close the tank compartment (eliminating the need for the previous cover) and will be fixed with two screws (in the future these screws can be replaced by magnets).
Screws will go on the red marks

 

[cdfigueredo]

EDIT: this new design makes me want to stick a small fan on front for active air flow

I don't think it will be necessary to add the fan. I am convinced that the airflow will be sufficient to expel the powder. But nothing is set in stone, only flight tests will tell the final word.

 

[cdfigueredo]

Version 2 is ready for printing. I am in love with this variant, I hope it works properly.

 

[Tench745]

Reminds me a bit of the mini-sub they use in Hunt For Red October.

 

[cdfigueredo]

I tested today the first prototype on my modified bushwacker and i have to say it works. Today was a really cloudy and windy day so the effect could only be seen when the model passed in front of the trees in the background. I used wheat flour for these tests and made a total of 3 flights, the first two without using the canopy and the last one using it. I have to say that I could not appreciate significant differences between using it or not, apart from the added weight. Maybe if I used some colored powder the effect would have been more noticeable on a cloudy day like today. it would also be convenient to try other less compact powders, wheat flour is quite heavy and tends to make compact lumps easily.

However, I can say that it works and it's fun. Actually the smoke time is quite short, but I think it can be adjusted with various modifications. What is for sure is that it is much more convenient to use a 2 or 3 position switch to operate the mechanism, because when using the pot I found myself in every attempt pushing it to the end of the travel.

Here is the video

 

[Tench745]

I tested today the first prototype on my modified bushwacker and i have to say it works. Today was a really cloudy and windy day so the effect could only be seen when the model passed in front of the trees in the background. I used wheat flour for these tests and made a total of 3 flights, the first two without using the canopy and the last one using it. I have to say that I could not appreciate significant differences between using it or not, apart from the added weight. Maybe if I used some colored powder the effect would have been more noticeable on a cloudy day like today. it would also be convenient to try other less compact powders, wheat flour is quite heavy and tends to make compact lumps easily.

However, I can say that it works and it's fun. Actually the smoke time is quite short, but I think it can be adjusted with various modifications. What is for sure is that it is much more convenient to use a 2 or 3 position switch to operate the mechanism, because when using the pot I found myself in every attempt pushing it to the end of the travel.

Here is the video

That looks pretty promising!
A thought on the transmitter: If you have something capable of more complex programming you might be able to set a momentary switch to advance the servo a certain amount every time you press it.

 

[cdfigueredo]

That looks pretty promising!
A thought on the transmitter: If you have something capable of more complex programming you might be able to set a momentary switch to advance the servo a certain amount every time you press it.

I have a JumperT16 so it could be achived, i will try it later.

 

[chickenhawk]

Just a couple of dumb questions, is there need for the air intake at the front? ( as the screw is moving the flour to the rear anyway) And would slowing the RPM of the servo help?

 

[cdfigueredo]

Just a couple of dumb questions, is there need for the air intake at the front? ( as the screw is moving the flour to the rear anyway) And would slowing the RPM of the servo help?

There are no dumb questions here 😅. I couldn't notice any difference between using the air intake or not so I will say there is no need, and also u save weight if not use it.
And yes, slowing the servo rpm helps to enlarge the duration of the smoke but also decrease the amount of powder dispensed so the smoke effect is also attenuate. I need to find the right balance.

 

[cdfigueredo]

Just a couple of dumb questions, is there need for the air intake at the front? ( as the screw is moving the flour to the rear anyway) And would slowing the RPM of the servo help

Also using other powers could help a lot.
Btw is there any site to buy colored powder at a reasonable price?

 

[chickenhawk]

When I was trying to get my other design to work I mixed coloured poster paint powder with baby powder. Got from dollar store, cheep as all get out and does not take much to tint the whole batch. I think it was $3.00 for 1/2 a quart.

 

[cdfigueredo]

When I was trying to get my other design to work I mixed coloured poster paint powder with baby powder. Got from dollar store, cheep as all get out and does not take much to tint the whole batch. I think it was $3.00 for 1/2 a quart.

like this one?

 

[chickenhawk]

Some thing like that, it was a dry poster paint ( you mixed with water) but mine were in large tubs. Sold by weight but the bottle was just over 1/2 a quart in size. Bright red seamed to work best. The rest went to the grandkids, Not by choice LOL

 

[chickenhawk]

Also don't mix in you wife's mixer, or if you do cover the top first or start with slow speed.

 

[Apis]

Also don't mix in you wife's mixer, or if you do cover the top first or start with slow speed.

Sounds like some personal experience here.

 

[cdfigueredo]

Some thing like that, it was a dry poster paint ( you mixed with water) but mine were in large tubs. Sold by weight but the bottle was just over 1/2 a quart in size. Bright red seamed to work best. The rest went to the grandkids, Not by choice LOL

Youtube is full of videos on how to make colored powder using cornstarch and food coloring. I just had to look. I saw another video where they used acrylic paint and I happened to have bought a small bottle of red at the dollar tree a few days ago. I already have my mixture made, tomorrow I will dry it in the sun.

 

[cdfigueredo]

The weather here is cloudy, so I didn't have the patience to dry it in the sun. I put the oven at 170 degrees with the door open to let the humidity out and it is almost dry. Soon I will have a fight with my wife when it's time to use the blender .



This shade of red looks quite bright, although I think it will lighten up a bit once it is completely dry, but I'm happy with the result. I am amazed at how easy it is to make colored powder and it takes relatively little time.

 

[cdfigueredo]

It is a little surprising that with how easy it is to make this type of colored powder and having so many models with a bay to throw candy, bombs or parachutes, I have not seen before any RC model making a fire extinguisher.

 

[cdfigueredo]

Version 2 is ready for assembly and testing soon.

 

[Apis]

The major change is mostly related to the housing and assembly (between v1 & V2), correct? So you expect any major change to performance with this model?