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Posted

It is strange though, to see display pics that im used to have changed.

 

I made some Barium salts recently - BaNO3 and BaCl

Its something to do when I out of chems for pyro. ;)

Posted

Well, I like the new look. I'm sure the forum will be populated in no time, too. Time to go make some color stars to celebrate the new forum. ;)

 

M

Posted

Nice to know everyone likes the new forum. I thought it would probably be a good idea to come out from behind the scenes! I did most of the work on the default skin, it's a different skin edited rather than started from scratch, are there any obvious improvements people would like to see?

 

As for the info pool, the files will be hosted on the board, and the forum itself already exists as mumbles said, we just havn't given any access to it yet.

Posted
The only improvement I would like to see is the fact that the forum doesn't actually take up the whole screen. There is about an inch or so on each side of wasted space and i'd rather see it a more wider fullscreen version if possible.
Posted
I've stretched it from 83% width to 90% width, is that better?
Posted

Hey justanotherpyro you could do what the gun companies do to test muzzle velocity. You can make a pendulum like set up where there is a box hanging from strings. The open end of the box will be on the horizontal. You launch a dummy shell into the box and see how high the pendulum box goes. Then you can use this equation.

 

(m1)(V1)+(m2)(v2)= MV

 

M1 is the mass of the dummy and V1 is the speed of the dummy (Pretty close to the muzzle velocity if you keep the launcher close to the open end of the box)

 

M2 is the weight of the box and V2 is the initial speed of the box (which is zero)

 

The last M is the weight of box+shell and the final V is dertermined below.

 

gh=((v^2)/2)

where g is the acclerarion due to gravity (9.8)

and h is the maximum height your box rose to

 

Now that you have the v plug it into the first equaton to get v1 which is the velocity you are looking for.

**This isn't entirely accurate but if you keep the mortar pretty close to the open end of the box you will come really close.**

Posted
Does anybody here play any type of musical instrument? I play electric, bass, and acoustic guitar. I also play some drums and piano but I'm best at the guitar since I play daily. I have an ESP F-50 6 string electric and a Marshall half-cab.
Posted

Good choice with the ESP there _DB_. I've got a V-250 (yes, the silly V shaped one), a tanglewood electro-acousitc, and I enjoy playing my friends bass on occaision. I also own a French horn, but I haven't got it out for a few years now - playing classical music in an orchestra isn't exactly my idea of fun anymore - I prefer pyro and heavy metal now :rolleyes:

 

On a pyro-related note, has anyone tried converting commercial quickmatch into jumping crackers with any success?

Posted

Yeah, I play trumpet, piano, viola, and violin. Not as much as I used to, mostly I only plat trumpet as of now.

 

My 40g of cast ETN/TNP only partially detted, I dont think the TNP did. Oh well, as the 11g of ETN/NG plastique was amazing. Caps consisited of .5g AP for each.

Posted

Ah, and so, the entirety of our world was created in a bang. This single cataclysmic event led to the universe with its galexies, solar systems, and our earth. We have too bean created out of the flame and the bang. APC has risen again! B)

 

Heh, I didn't get VIP but was close. This forum, in my opinion, reminds me of kbk's, or at least the setup. This will take some getting used to.

 

I hope that this forum evolves into the respected being that was the last.

Posted
Is there a way to calculate the initial velocity of a shell being fired out of a mortar? I know there will be several constants needed like barrel length and the quality of the BP to determine gas output in an amount of time etc... I just need something to start working with. Any formulae would be great.

You may want to try this......

 

Don't calculate. Get a cronograph. They can be had relatively cheaply from variouse paintball places online. All you'll need to do is figure out a way to mount it to a mortar. If you do this I highly suggest that you are a good distance away from your mortar/cronograph contraption....don't want any pieces of cronograph stuck in your eye.

 

Obviously the crono will most likely give you FPS so you'll have to convert that to MPH.

 

Then again, most crono's only go to 999FPS which is 681.14MPH. Look for a crono that goes higher.

 

999FPS is 681.14MPH right? My brain has turned to slush this past week.

 

LOL, then again, they make crono's for guns, so there must be relatively cheap crono's that can measure higher. Look around.

 

EDIT:

 

Hey WTF is this "Warn" thing and why doesn't anyone else have it?

Posted
Good Idea Kilo_G. I changed the practical application of maximum height of a shell, to theoretical height of a 100g lead projectile and I switched from BP to NC based smokeless powder because I found some good data on NC, PSI, velocity etc...
Posted
Hey everybody! The new forum looks pretty sweet. Its a lot... sharper looking than the old one. Just started making my first "real" batch of bp. All my others were made with the horrible kitchen scale I used to have. Now I got the .01 gram jewelry scale. The only problem now is my piece of crap ball mill which consists of a Playdow jar, a power windows motor from a car, a 12 volt battery, and a small assortment of Lego pieces. :)
Posted
I'm gonna have to say that that takes the cake for gettoest ball mill ever created, if that really is your ball mill.
Posted
Yeah that's my ball mill. <_< For milling media I use sinkers. They kinda suck because when I took out the Mg thats been in there for like 8 months I found some little chunks of lead from them. One of the worst things is that the window motor isnt really that great and tends to get extremely hot within a half hour of use. So, its probably going to take me at least a week to get halfway decently milled bp. Last year I made it work a little longer by sitting there and putting chunks of snow on the motor casing to cool it down. It kind of worked. Snow all melted the other day though, so I can't use that method right now.
Posted

It womt let me edit my avatar, has this happend to anyone?

 

 

This forum of so much better them the last one!

Posted
Heh, I would say a window motor wouldn't be the best choice there. Maybe a geared down fan motor would do the trick. As your milling jar isn't very large, it won't need a large amount of power to turn. With a fan motor, it usually won't overheat with a lot of use too, so you won't need to add a slush to the casing :P
Posted
Yeah I know. I've got a 2hp motor I pulled out of a shop vac that I've been planning to use but haven't got around to it. I'd have to gear it down so much though and pulleys around here are expensive. I dont know if it would be cheaper to buy one or not. For now my playdow mill will have to do the trick.
Posted

I'd highly suggest that you either buy a mill from www.hobbyfireworks.com or buy Lloyd's book on how to properly construct a ball mill. If you get a subscription from www.passfire.com there is also a tutorial on there of how to properly construct a ball mill.

 

If I were you, money and knowledge wise, your best bet would be to get a passfire subscription, though hobby fireworks makes good stuff.

Posted

W00t this place looks great!

 

Edit: Something random... I am hopefully going to be distilling my own alcohol soon...Wish us luck.

Posted
I'm having trouble accessing my control panel, it won't let me in. What gives?
Posted

Not sure, I assume you've been clicking then "my control panel" buttom. I nkow you did, but there is something else up there that you should be able to get there. If computer illiterate me can get to it, iI'm positive you can.

 

I think you mentioned this before but what does that warning message mean. Is it like, I don't like your post so staighten up or you get a warning?

Posted

No, it's like a warning meter, mine's at 0%.

 

I clicked the "My Controls" link up top, never had a problem with it before until a few minutes ago.

 

EDIT:

 

When I click it it gives me a "Parse error" and then a big long line to some root directory.

Posted
Yeah I know. I've got a 2hp motor I pulled out of a shop vac that I've been planning to use but haven't got around to it. I'd have to gear it down so much though and pulleys around here are expensive. I dont know if it would be cheaper to buy one or not. For now my playdow mill will have to do the trick.

Why not just buy a harbor freight rock tumbler they are pretty cheep and they work pretty well, however it will take you one or two days to get good bp.

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