Do you have a micrometer? The wire diameter is key.
Exactly, I was to ask about the same. 
Or use a digital fish scale to measure the spring force. But I guess your goal was to make the leg “in balance” when standing without power?
my multimeter is broke! 
i think its just down to trial or error when testing the springs. you can buy 150piece spring assortments for only a few $. but the wire think need looks to be 1mm.
i have already made an improvement to the spring position and i have also worked out position for hip spring. 
all will be clear tonight when i take a picture.
Sounds like your having fun! Looking forward to see some more pics. 
I love the leg design. I look forward to more!
And here it is.
**Here i have started exsperimenting with different points of force on the spring. **
The ball joint make it very easy to amment this.
http://i531.photobucket.com/albums/dd355/innerbreed/100_2694.jpg
having done so it seems that the original place is enough to keep it standing.
Here shows the new hip spring. still have to experiment with this one, but for now its working.
http://i531.photobucket.com/albums/dd355/innerbreed/100_2693.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/100_2690.jpg
Posing With No Power!
http://i531.photobucket.com/albums/dd355/innerbreed/100_2691.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/100_2697.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/100_2698.jpg
From the time I first saw this thread start I just knew it would turn into a full fledged robot sometime. Great work, I really admire the way you used those load balancing springs.
Awesome and very inspiring Jonny! 8)
Very clever way you solved the hip spring. Your brackets show very clear that you’ve played with them a lot before…
Have fun!
Jonny,
What is that cam-shaped piece on the horn? Is it an ASB-19B?
What size ball links do you use? …or what is the hole size on the ASB-19b?
I’ve used the adjustable length plastic horn that came with the servos, but those at the base of Peter Penguin are stating to flex and bend. They take the largest moment of force.
BTW, in addition to Jolly Black Giant, JBG could stand for Jonny’s Big Guy…
Jonny!
How about the 'Quad? (Not that I can talk).
Alan KM6VV
ASB-19B is correct. i do wish to change this for a custom piece.
The ball joint has a 2–56 x 1/4" threaded stud.
lynxmotion.com/p-339-ball-li … -pair.aspx
http://www.active-robots.com/products/motorsandwheels/ball-link-set/bls-01-500.jpg
Alan the AXIS quad is still in development. im kinda stuck with the Terrain Adaptive switches. im taking the easy route with this one and waiting till someone else has the patience to get the code working. but for now its still running on my original code.
Good to hear the AXIS quad is still a project. I will get some time to work on my Little Cat this weekend. Finally (mostly) over the walking pneumonia + ear infection.
I’ve still not figured out the ball link parts. What all to order. A few days ago I saw some new parts for one of our medical robots. Ball screws driving dog bone links connected to a swash-plate. Neat mechanism!
Alan KM6VV
Thanks Jonny - I have the 1/16 ball joints and it looked like they would be two small for the ASB-19B.
dj
im curious to see what you are building? is this for peter?
i have just tried to program this bad boy with some code i wrote last night.
need lots and lots of tweaking. 
im not sure this will actually walk but ill give it a go. might have to use my biped converted powerpod code i did earlier this year.
remember this approach?:
http://i531.photobucket.com/albums/dd355/innerbreed/legcompare.jpg
http://i531.photobucket.com/albums/dd355/innerbreed/bps01.jpg
I would like to second or was that third or fourth that you are doing great stuff on this!
I am not sure how far I will get with some of this, but I am finally in the process of converting the legs on my CHR-3 to ones with the switches. I have 7 our of 8 legs changed over. Then need to change the config for the differences, then wire in the switches and then I can play with this. Not sure how fast I will get going on this as I am still having fun with my C library code. Also wish to finish getting a new hacked RC control version for the code working…
Kurt
7 or 8 legs? Sounds like an Octopus!
Alan KM6VV
OOps I can not count… it was 5 out of 6. Now 6 out of 6, cleaning up wiring a bit, and then off to change config, zero servos…
Kurt
sounds like you are making progress kurt.
hope you have more success than i have. im really anxious to get AXIS TA walking.
I am also looking at creating some shells as outer casing. 8)
My problem is ideas are still hitting me in the head for other projects. i have an idea for a new type of hexapod that i mentioned to Matt Denton about last year. I haven’t solved a few problems that i will run into so for now 'in till that day comes, ill keep this one a secret.
lets just say… its more Mechanical Art than a hobby toy. saying that, it will have all the common features to date!
just need to get my hands on either one of these!
at the moment im looking at what will work best.
Jonny,
With your skills, the latter should be easy enough to cut out!
Alan KM6VV