Slinging.org Forum
https://slinging.org/forum/YaBB.pl
General >> General Slinging Discussion >> Chronograph
https://slinging.org/forum/YaBB.pl?num=1534156056

Message started by Mersa on Aug 13th, 2018 at 6:27am

Title: Chronograph
Post by Mersa on Aug 13th, 2018 at 6:27am
So as I understand there are none or very little records of chronographs being used to measure sling projectiles with actual slingers.
As a group can we get this done??!!

Title: Re: Chronograph
Post by Morphy on Aug 13th, 2018 at 8:07am
I've heard of people using audacity and radar guns. But Chronies would be nice for a good release velocity. Only problem I foresee is the high likelihood of destruction. Maybe cut out some sort of shield for the actual machine?

Title: Re: Chronograph
Post by woodssj on Aug 13th, 2018 at 1:59pm
This seems like a great project for the "Here Be Maths" section. And, with pre-weighed projectiles, we can clear up a lot of information on the effects of sling length, performance, and possible ranges of performance.

But I agree with Morphy: Those things are expensive, and would likely get damaged. Plus, their measured area is really small, which requires a precise throw to get it measured.

Some careful engineering and pursuit is at hand here, and I'd be glad to help in any way I can. Just let me know.

Title: Re: Chronograph
Post by Bill Skinner on Aug 13th, 2018 at 7:37pm
They aren't really expensive and a shield would be rather easy to build.  You can get an inexpensive one for a lot less than a phone or I pad.

The main problem will be the window, it's actually rather small.  And you will have to have the shades for it to work properly.  So, you would have to throw through a port in the shield for it to work. 

So, we'd need a really super accurate slinger, who can throw at full power and not get squirrely with his accuracy when he does so.

This actually sounds like a job for Timpa.   ;D

Title: Re: Chronograph
Post by Mersa on Aug 14th, 2018 at 2:48am
Same idea I had a window to shoot though so we don't go smashing the chronograph  first shot . Maybe I can talk my archery buddies into buying and sharing one.

Title: Re: Chronograph
Post by Bill Skinner on Aug 14th, 2018 at 12:58pm
MidwayUSA had an inexpensive model, last time I checked.  And it will record arrows.

Title: Re: Chronograph
Post by NooneOfConsequence on Aug 16th, 2018 at 12:33am
The poor man’s version would be two pieces of tissue paper held tight and spaced a known distance apart. Record audio and you can calculate speed from the time between each paper sound as the projectile breaks through the papers. No need for a chrony at all :)

Title: Re: Chronograph
Post by Curious Aardvark on Aug 16th, 2018 at 6:47am
goth dave has a chrono.

Dunno if he's posted any videos of it in use. 

Title: Re: Chronograph
Post by Morphy on Aug 16th, 2018 at 7:45am
https://youtu.be/BrtBc-9pQv4

Perhaps a set up like this? You could also measure rotational speed while your at it by painting the glande black and white as well. You wouldn't need a super expensive camera at sling speeds.

Title: Re: Chronograph
Post by Sarosh on Aug 16th, 2018 at 10:41am
@Morphy that's the way i do it. but there might be errors.
wait until weekend. i'm making a video with speed measurements by camera frames.

Title: Re: Chronograph
Post by Morphy on Aug 16th, 2018 at 11:22am

Sarosh wrote on Aug 16th, 2018 at 10:41am:
@Morphy that's the way i do it. but there might be errors.
wait until weekend. i'm making a video with speed measurements by camera frames.


What kind of camera are you using?

Title: Re: Chronograph
Post by Sarosh on Aug 16th, 2018 at 11:36am
720p 30fps the same you see in the videos i've uploaded.
hopefully i will find a phone with more fps in the future.

Title: Re: Chronograph
Post by Mersa on Aug 16th, 2018 at 6:55pm
Yeah I've thought about setting up distance markers and using audio or video to analyse it but I really want a chrony so it's there for everyone to see , sling projectiles can go ...... ?? Fps.
I've looked into the price and there around the 200 mark in Australia. Pout of reach for now but maybe possible later this year .

Title: Re: Chronograph
Post by woodssj on Aug 16th, 2018 at 9:03pm
I like the board and side camera idea. I'll have to try to set something similar up in future as well. Right now, I just don't have anywhere to do it.

I'm starting a new thread in the "Here Be Maths" section for your speed recordings and using what method. I'll create a similar Google Form to the one I've done for target results and we can compile some decent statistics from that over time.

I'm looking forward to hearing about the results in future!

(Also, when I create my regular slinging club in Northern NY/Southern VT, I'll be regularly uploading such results and I'll have both standard targets and a speed rig like the one described above. I'll let you know when that's established.)

Title: Re: Chronograph
Post by Dawesome21 on Aug 17th, 2018 at 2:31pm
I discovered this nice program lately that I used to clock a golf ball from a sling.  https://physlets.org/tracker/ ; I just set a stationary side camera and used the golf ball's diameter itself as the reference distance -- this might not have been the best idea, but it gave me a reasonable number -- about 85 fps I think.

Title: Re: Chronograph
Post by woodssj on Aug 17th, 2018 at 5:43pm
We're collecting data over here, once you've gotten some collected. I'm looking forward to the results!

http://slinging.org/forum/YaBB.pl?num=1534470400

Title: Re: Chronograph
Post by Sarosh on Jul 24th, 2019 at 4:07pm
just watched a video from joergsprave in which he used a new chronograph https://www.youtube.com/watch?v=1aZaiKGC-4A
go to 9:00 . but they are all so expensive... :(

Title: Re: Chronograph
Post by Morphy on Jul 24th, 2019 at 8:36pm
$200 for that one on one website I saw. Really quite reasonable although granted it's still a luxury item. I read some of the reviews and one guy mentioned it was prone to misreadings with slight changes in airgun barrel position. While that may not be a huge deal with an airgun I suspect it would be for slings.

Still I want it. That is the first legit "Chrono" for a sling. All the other ones scare me to use. Plus you could throw it in your back pack no problem. Good find Sarosh. (Also those bows were fantastic. I just wish someone could make an Oneida version of the triangle bow for asthetics.)  :)

Slinging.org Forum » Powered by YaBB 2.5.2!
YaBB Forum Software © 2000-2024. All Rights Reserved.