1lb rocket tooling!

[Jimjimboom]

Hi guys i have been playing around with home made tooling and today managed to get a rocket in the air nicely but i have ordered some proper tooling from a reputable dealer! I was wondering is 1lb rocket tooling talking about the weight of the rocket or the thrust produced by the rocket? As 500g rocket seems a bit heavy!

[davidh]

Neither. It has to do with an antique system involving lead balls. Just know that 1# BP rockets are made in a tube with a 3/4" ID and 7-1/2" long.

[BetICouldMake1]

3/8" ID "2-Ounce Motor" (1/8-Pound)

1/2" ID "4-Ounce Motor" (1/4-Pound)

5/8" ID "8-Ounce Motor" (1/2-Pound)

3/4" ID "One-Pound Motor"

7/8" ID "Two-Pound Motor"

1" ID "Three-Pound Motor"

1-1/4" ID "Four-Pound Motor"

1-1/2" ID "Six-Pound Motor"

Should you care about the history an excerpt from Hardt's Pyrotechnics:

While the dimensions of a skyrocket are rather straightforward once one understands them, the names assigned to the different sizes can be very confusing. Rockets have long been designated in terms of “ounces” and “pounds,* but those who bother to check will find that the actual, weight of the product for sale is not even close to its nominal size. The terminology originated in the days when rockets (and many other fireworks) were rammed in metal moulds. In those days there was not so much difference between military and civilian pyrotechny; many of the men who made display rockets were also gunners, who tended to think of all projectiles in terms of their external diameter. It is probable, that the ramming moulds were bored with the same reamers used for cannon barrels; indeed some of them might even have been made from pieces of discarded guns. It was decided that the internal diameter of a. rocket ought to be two thirds of its external diameter, a ratio which st ill .for the most part holds true. A bit of rounding-off was inevitable. A quarter-pound lead ball measures just over an inch, and if this is rounded to an outside diameter of 1 1/8” the inside diameter of the quarter - pound rocket case becomes a convenient ¾” A one-pounder cannon had a bore of a little less than two inches, and would correspond to a rocket: with a bore of 1 1/4.

 

It can be seen that, although this nomenclature would always have been confusing to an outsider, it was not arbitrary. Most of those in a position to become pyrotechnists knew the size of half-pound, one-pound, or two-pound artillery as a matter of course. The key dimension of a rocket was its external diameter, and all its other dimensions were easily calculated from this. The same formulae could be used to determine the dimensions for rockets which did not correspond to any standard size gun, including some so small that they were designated in drams rather than ounces. As ramming in moulds was gradually abandoned, it became convenient to think in terms of the internal, diameters of the rockets, but the sizes remained the same.

[Micahama]

I have some 1 inch diameter, six inch length, cardboard rocket tubing i had purchased from amazon. I use KNO3(65%) and powdered sugar (35%) with an additional bit of rust powder i scraped from an old car added, outside of the previous kno3/sugar percentages, that I melt in a pan over an electric heat conducting unit on medium power, this produces a brownish paste, that when fluid, I pour into the previously mentioned cardboard motor tubing above a slightly variably grater than one inch hard play-doh end-cap sealed with hot glue on the skyward face of the motor, i was wondering what diameter, what length, what to use as a nozzle / if i should use a nozzle, and what tools i could use to core the rocket if produced the way i had described previous to my questioning. Otherwise if you know a better methodology with the same available materials please enlighten me with GREAT detail. also i was wondering if "Starlight" The Un-burnable material (if you haent seen it its Elmers glue, corn starch, and baking soda mixed in at a ratio with a little water that makes a flame insulation type putty when hardened over time) could be used for nozzles or applied anywhere else in the scheme of pyrotechnics and or rocketry, but most specifically rocketry. please support me i am completely uneducated and this is my first post on this forum......

[JMan]

TL;DR: good start, nozzle diameter is 1/12 length, store your motors in a dry space, did you core your motor?, and be safe

 

Sounds like you know your stuff. Guess youve been reading. But for how detailed you made this post, Im guessing your missing a few things.

 

About the nozzle first: Most people suggest the use of quick set cement (or water putty? I forget the brand name) for nozzle diameter, a rough estimate is 1/12 of the length of your core.

 

First thing I noticed. Make sure you keep your sugar rocket fuel in a very very dry place. It will be useless if you try to use it after just a few hours of sitting even inside (well, maybe not unless for just a few hours but you will noticed the difference and it will likely fail the mission). Give it a few days and it may not burn.

 

Second, are you coring your motors? You described a lot but did not say if you put a core or what diameter core you have. Sugar rockets just almost dont have enough kick to be end burning rocket motors so giving them a hollow core to burn more fuel at once really gives them the kick they need. (Blackpowder doesnt always need this trick but even the black powder rockets usually use this trick to boost their performance).

 

But, if this is your first time, most importantly make long fuses and be far away from your rockets when launching, you never know when theyll blow up, or (usually thought of less) not have enough thrust (from day, being left out in the air for a few hours) and turn sideways and head straight for you (or a car or a house).

[Jimjimboom]

Thanks for the info guys! I have had a few more catos so i tried a few end burners and had some success and a few failures! I will try the sugar rocket but i ordered some sorbitol to use for it! And really loving the hobby, keen to get in touch with anyone in australia, that is into this hobby

[JMan]

Let me know how sorbitol goes, Ive tried it and always found it way too sticky and malleable to do anything with. If you find the same problem, Id recommend erythritol. It is non hygroscopic and this makes it very hard to mess up. The only problem is it only behaves (or burns) rocket fuel like under a good amount of pressure, so you need small nozzles or big rockets.