1569 replies to this topic

[paul]

The stars were SilverStreamer. (Shimizu GoldenWave N?3)

The lift-effect was a 25mm no-antimony white glitter with Ti substituted with Al...

No, I did not use flash cores. But the stars were primed heavily, so a few of them lighted too late.

greets,

paul

[LadyKate]

I plan on doing more tests using benzolift, i have used it to shoot a small (25mm) bombette and it made the poor thing go really high. When i complete more tests i will post the results.

k

I just made my second batch and it is much less powerful than the first. The basic formula was followed in both instances but there were some differences:

Batch 1: Potassium Benzoate, Perc, BP Dust after compressing to 1.7gr/cc.

Batch 2: Sodium Benzoate, Perc, Charcoal, Sodium Nitrate, Sulphur (75/15/10) all mixed at the same time (Perc last after wetting).

Batch number 1 required 3 grams to send my dummy 1.75" mortar shell up. This is much more powerful than 2Fg.

Batch number 2 required 5 grams to send my dummy 1.75" mortar shell up. This is about what 2Fg powder would do (not quite).

While this is unscientific, it does show that Benzolift can have quite a bit of variability. This seems to contradict the idea that you can just throw the ingredients together and get about the same quality of Benzolift each time.

My conclusion (it ain't earth shaking) is that to get repeatable results, one should carefully pick a formula and methodology and stick to it. I think just mixing in the ingredients for green mix works but does not produce as vigorous a lift powder as using properly prepared BP

Edited by LadyKate, 29 July 2005 - 12:20 PM.

[karlfoxman]

Thanks that is very helpful, i have been using sodium benzoate for my benzolift. I have read somewhere that potassium benzoate is slightly quicker than sodium benzoate. My tests are on hold as i have very very little perc left now!! Anyone use grass seeds as carrier for burst charges??

Karl

[LadyKate]

Thanks that is very helpful, i have been using sodium benzoate for my benzolift. I have read somewhere that potassium benzoate is slightly quicker than sodium benzoate. My tests are on hold as i have very very little perc left now!!    Anyone use grass seeds as carrier for burst charges??

Karl

Could the difference between the Potassium and Sodium Benzoates merely be the Sodium version's tendancy to draw moisture? I couldn't tell much difference between the two when all other variables were equal.

I haven't used grass seed - would be interested in finding out how well it works. I have used Rice Krispies (a puffed rice product) and that works fine - although the flakes are big (not a drawback if you are filling space).

I just received some empty plastic 2" cylinders so I'm ready to experiment. The first thing I noticed is that it holds a lot more than the round shell does! A lift enhancement that seems really easy (haven't tried it) is to use some Falling Leaves fuse for the delay fuse. I'll try it first - it's cheap!

[karlfoxman]

Today i will make a 2" cylidrical shell with willow bp on grass seeds. i will put just two of my gold tourbillions and one small bp banger inside. With my mob i will photograph the parts and the finished shell. More to follow as i only just started it......

So sodium benzoate is gives almost the same performance as potassium benzoate, thats good then as i can get loads and loads of sodium benzoate!!!!

Edited by karlfoxman, 30 July 2005 - 11:30 AM.

[karlfoxman]

Well here it is, the two blue tubes are the tourbillions filled and primed.

This is the bursting charge willow bp on grass seeds, with casing and spoolette glued to disks.

Finished shell ready for quickmatch leader, lift charge and label.



Karl

[ProfHawking]

Looks very nice!
how much does it weigh?

video is always a treat, you got a camera?

[karlfoxman]

I dont have a camera, i will try to borrow one if i can. I think i will wait a while before setting it off. I need to get some 2" mortars ya see. Its weight is 89g on its own.



Spoolette end drying, string around the spoolette to stop flowerpot. This idea was from a vulcan shell on passfire

Edited by karlfoxman, 31 July 2005 - 06:47 AM.

[karlfoxman]

Wow i am happy, my burst worked great!!!! I didnt fire it out a mortar, i had it on a electric igniter 40 feet away on the ground......all the tourbillions lit and the burst was strong. it used my first batch of un milled bp on grass seeds. Very pleased. Next one will have hummers inside and maybe pill box stars.

Edited by karlfoxman, 02 August 2005 - 08:53 PM.

[karlfoxman]

GUYS!!!! I need help, how much lift is ok for a 5 inch spherical shell? passfire says 113g! is that too much? oh and its home made powdered bp 75/15/10 kno3/c/s using willow charcoal.

Edited by karlfoxman, 06 August 2005 - 08:21 PM.

[italteen3]

Use the 1/16 rule. 1/16 of the shell's weight you use as lift, roughly. There are a lot of different factors that can determine how much lift to use. How does your BP compare to commercial, how high do you want your shell to go, etc.

[karlfoxman]

I have gone for 40g, my bp is fairly good for lifting. I will go for 40g as my 4" use 25g. Thanks for you help. I have a few pictures to upload, the shell is looking good!

[LadyKate]

I have gone for 40g, my bp is fairly good for lifting. I will go for 40g as my 4" use 25g. Thanks for you help. I have a few pictures to upload, the shell is looking good!

You might want to launch a test shell before you launch your live one. I always send a few tests up when I move to a new size or configuration. Fill a dummy shell with flour or dog food and see if 40g is enough. With a test shell, you can launch it in the daylight, and if luck is with you, the shell will survive to test again.

[UncleBuck]

I had the same problem. But I tried useing paper hemis from china and not plastic.
I solved the problem by makeing my own paper-hemi press. Made out of fine cement and a wooden plugg to press out the paper into a spherical shape.

What did you use to make the semi-circle impression in the cement?

Also what is the largest mold you have made? I was thinking of making a 6 inch mold but was told the larger paper shells are very hard to make.

[karlfoxman]

Here is some pictures of my latest shell, its a 5 inch spherical shell with 2 3.8 second spoolettes...its called BLUE SPLITTING STARS W/ GOLD PISTIL

Hemis with spoolettes

Looking at spoolettes

Lift cone with tissue bag of 40g powdered willow bp

Empty splitting star cases sitting inside shell hemi (20 of them)

Looking good so far


Karl