My New DIY Chronograph!!!

cwazy1 · Sun Dec 23, 2007 7:53 pm

so heres my new DIY chrono, i personally think that it looks nicer than the "chrony" but eh tell me what you think.

heres the insides

and heres the finished product, all closed up

i am testing it right now as i type becuaes im dling the audio program. =)

Thursto · Sun Dec 23, 2007 8:02 pm

WOW, thats is neat ass! I wish i could make one, how accurate does it read?? Hae you tested it yet? The finish product looks very clean, and overall looks sick as! Job well done.

~ Thursto

cwazy1 · Sun Dec 23, 2007 8:12 pm

well i just dl-ed the audacity and well at least now i know it works!! YESSS i just have to find out hot to find the time between two points.

bigbob12345 · Sun Dec 23, 2007 8:14 pm

Very nicely done what did you use to make it

cwazy1 · Sun Dec 23, 2007 8:19 pm

umm i used photocells and LEDs....really simple design expecially if you've done some electrical stuff (i play with coilguns)

cwazy1 · Sun Dec 23, 2007 8:27 pm

ok i just tested it and i think its about accurate, i shot a rubber band through it and it recorded 38.5fps...well thats reasonable.

potatoflinger · Sun Dec 23, 2007 9:25 pm

Nice, it looks like it should work, as long as what you're shooting crosses directly between the photocell and the LED, but that won't be a problem unless you're shooting something small like a bb or an airsoft pellet. It also looks very clean, great job.

cwazy1 · Sun Dec 23, 2007 9:30 pm

i just clocked a bb blown out of a straw, it definitly clocked it at 68.8fps

Novacastrian · Sun Dec 23, 2007 9:43 pm

Looks neat as, but to know if it is accurate you would have to test it side by side a real one. Good job.

mopherman · Sun Dec 23, 2007 10:37 pm

Have you compared it with ggdt? I'm surprised you were able to tst such small things as bbs. Were did you find out the works of this?

TurboSuper · Sun Dec 23, 2007 10:49 pm

That looks pretty neat, and the photocells should give you a fairly good response time too.

I guess if you really wanted to get fancy, you could embed a timer directly into it.

cwazy1 · Sun Dec 23, 2007 10:57 pm

i will compare to ggdt tomrw morning.. the only bad thing is that the bb's have to be dark color ( atleast orange/yellow) because my glow in the dark ones dont work.

hha if i REALLY wanted to get fancy, i would put 2 laser pointers on the photo cells instead so i can even use a TINY projectile.

Check out my YouTube SpudGun Channel! · Sun Dec 23, 2007 11:10 pm

mopherman wrote:Have you compared it with ggdt? I'm surprised you were able to tst such small things as bbs. Were did you find out the works of this?

I wouldn't trust GGDT a helluva lot. A chrony would be far better.

mopherman · Sun Dec 23, 2007 11:19 pm

MrCrowley wrote:
mopherman wrote:Have you compared it with ggdt? I'm surprised you were able to tst such small things as bbs. Were did you find out the works of this?
I wouldn't trust GGDT a helluva lot. A chrony would be far better.

I know, but if they match up at lower speeds, you know that its at least accurate to some degree. If he had a chrony to use, why make this anyway?

Check out my YouTube SpudGun Channel! · Sun Dec 23, 2007 11:27 pm

cwazy1 wrote:i personally think that it looks nicer than the "chrony" but eh tell me what you think.

Also he could've made it for sh|ts and gigs, or he may have access to a chrony.

GGDT and this chrony could end up with different results at higher pressures. The sensors may give a bad reading at higher pressures and GGDT has loads of problems.

It's never modelled my piston gun decently, it's still over 110m off with it's distance calculator.
And since finding the distance heavily involves it's fps, it's muzzle velocity must be wrong too.