Cone Fountains

[warthog]

To make my stands so that I could hold the cones inverted so they could be filled, I used plaster of paris. I allowed the plaster of paris to begin to set up, takes around 10 minutes for it to thicken, then I pushed my "Mold Cone" into the mass and began tapping the sides of the container to remove as many of the large bubbles as I could from the plaster.

I used a special level so I could make sure I had the cone in there upright, seen in the second picture. I turned the cone in the plaster now and then to keep it from sticking plus I had also sprayed some sealer on the cone and prior to pushing it into the paster made sure the sealed area was wet.

 

As it came to a point where the plaster had set but wasn't quite cured, I pulled the cone out of the hole and wet the sealed area again, then pushed it back into the hole and twirled it round. Doing this makes the inside of the hole nice and smooth so that it won't tear up the cones when in use.

 

 

Here you can see how deep the cone is when in the stand, I marked it with a line.

 

 

This gives a good view down into the stand while a cone is in it. The dowels will become the tamping tools to be used when filling the cones with composition.

 

There are the two stands I was able to make before my 4 lb. box of plaster ran out. I then tapered one end of the 1.5" dowel enough to fit into the one at about where I wanted the first increment to end, then the other side, the untapered one, is used for the second and the 2" dowel does the last bit before I glue an end disk in place over the comp then set it aside to dry.

 

The first increment is put in damp, then the next are put in dry and the moisture in the first increment migrates to harden the whole into a nice, solid block. Once dry I will drill a hole by hand so I can put a piece of visco in place. This will be held in place by some NCL/mill dust slurry. Finally the cone is wrapped in 30# Kraft and now it is ready to light. The kraft paper and cone insides are treated with a 50/50 waterglass/distilled water solution for fireproofing. This allows the paper to become a sort of nozzle so the sparks will go higher and I hope to make the cone reusable at east once or twice.

Edited February 22, 2012 by warthog

[JFeve81]

Looks good. Is there any chance you might go into more detail with pictures on the filling procedure?

[warthog]

Looks good. Is there any chance you might go into more detail with pictures on the filling procedure?

 

I absolutely will do just that with pictures, the formula I am using and finally a video of the fountain at work.

This will be done promptly once Lent has ended, I will post it to this thread as I have it bookmarked.

 

I can outline it for you now though:

 

I plan on using a simple BP Type fountain mixture with "grape nuts" Ferro-Ti added to it for sparking action. I will also add 5% dextrin to the mixture as a binder. While I do not yet know how much I will need to use of the mixture to fill the cone 1/3rd of the way each time, that is what I will use an an increment. I will moisten the first third of the mix as though I were pumping stars then I will put this into the cone as the first increment. Using the tapered end of the 1.5" dowel, I will then press this into the cone firmly with just hand pressure. No rawhide hammer nor press, just a good firm push down with the dowel. The next 2/3rds go in dry, each one getting the same sort of firm pressure with the proper dowel or dowel end with just hand pressure. When I have the last one pressed into the cone I will use some "Pyro Adhesive" to glue a paper disk in the bottom of the cone over the last bit of the mix. Once the adhesive is set up, I will take the finished cone out of the stand and put it aside to dry. The moisture from the first increment should migrate throughout the whole mass and once dry it ill form a nice, solid block of fountain stuff. Finally, using a drill bit and my fingers, I will take a 3/16" bit and make a hole in the center of the opening and using a slurry of NCL & mill dust, glue a piece of visco into the hole I just drilled, Once this dries I will wrap at least the upper part of the cone wit some 60# Kraft that has been treated with waterglass bringing the top to a point. This paper will be the nozzle for the fountain to make the sparks go higher and make the fountain perform better in general. The finished cone will wind up being around 1/3rd full leaving the bottom 2/3rds hollow like most commercial cones.

 

That's it in a nutshell! Here are a couple of formulae:

 

BP Fountain Mix:

KNO₃------------------66%

Airfloat Charcoal---24%

Sulfur------------------10%

Ferro-Ti-------------(+10%)

Dextrin---------------(+5%)

Screen all chemicals together thoroughly except the metal with a 40 mesh or finer screen. Make sure all of your chemicals are as fine as you can make them. I generally run my KNO₃ through my coffee grinder a little at a time until it is nice and finely ground. Once the basic elements are well mixed, add in the metal and either stir or shake this into the mix as well as you can manage. Give the mix a stir or shake as you fill the cone as well and the metal will settle out because of the weight difference. You want to get it as well dispersed into the mx as you are able to get done.

 

Pyro Adhesive

Sodium Silicate---------100

Calcium Carbonate-------5

Zinc Oxide-------------------5

(parts by weight)

The silicate should be a syrupy consistency. There are no set proportions for the calcium carbonate and zinc oxide. The zinc oxide makes a stronger adhesive, but is not necessary. Fireclay may also replace all or part of the calcium carbonate. All additives are added until the desired consistency is achieved, usually a smooth mixture that will not run when applied.

 

This stuff sets up into a solid once mixed. Mix only as much as can be used at one time, as it can not be stored once mixed. Do not dry in sunlight or dry times will be greatly increased due to a quick forming skin on the surface.

Edited February 23, 2012 by warthog

[spitfire]

very interesting warthog, thanks for sharing! I always wanted to make my own cone fountains because of good memories that got me into pyro in the first place. They are just fun and a typical product that brings back memories Most pyro's concentrate on big shells or whistle rockets that launch a 6'' shell, but i like the old fashion chinese things! This is one of them.