Someone sent me inquiry about this recently and I don't remember who it was or where it came from ... this messageboard, pm, email, or from the social schmocial politically correct 'facebook' which I do not participate much. I must have accidentally deleted that message.
The person I think read the Stop Motion Works Ol' Classic & Infamous Open Hole Ball Joints ....
The inquiry question was: What are some of the advantages & disadvantages of 'Open Hole Ball Joints'??
Surely ... many of you savvy, information compulsive hungry kids out here, can analyze the differences or pros & cons between Open Hole Joints and Milled-style Socketed Joints???? Put on your thinking caps and discuss amongst yourselves ....
Oh-oh-I know!-I know! Open hole ball joints are 0.023% lighter than milled sockets! What do I win?
How about a Kewpie doll? (Whatever that is!)
Only you're WRONG!!!
You're obviously thinking of Open Hole Pepsi - all the calories, none of the taste.
Some of the actual advantages would include:
You can make the open hole versions with just a few inexpensive tools like a drill press, hacksaw, hand files or maybe a dremel. They involve much less work and knowledge and are much more forgiving, not requiring the precise 'gnat's ass' tolerances (Hah! do I get extra points for that one?) necessary for the original recipe joints (wait - my analogy is falling apart now - I believe open hole joints were probably in use before ball and socket, or am I wrong there?)
To all entries, we appreciate your participation but there can be only one winner ... Strider WINS! As consolation prize, I was going to offer Hostess Twinkies or their Chocolate Cup Cakes (my favorite) but unfortunately, certain Dark Negative Forces 'out there' has shut Hostess down and they are no more, zero, non-existent .
Yes ... one can do Open Hole Joints with minimalistic equipment and be very portable. Rather than relying on much machining equipment ... the Armaturist using hand-tactile old world crafting techniques. To prepare for the upcoming power/energy shortages & brown-outs, you can probably construct stop motion armatures with almost NO electric power. You know ... out in the woods in a cabin. Get the tools Strider listed and ALSO - an old antique hand powered drill press & bench wheel grinder!
With regards to the 'Technical' - Open hole ball joints could be weaker than milled socketed joints such as in the ankles & toes where usually high joint tensions might be needed. The hole takes away some of the joint strength compared to having no hole or minimal hole (in milled sockets). Also, open holes might be slightly bulkier or larger .... HOWEVER ... in most cases, and if you are not into Burton'esque Skinny Arse Ankles & Wrists or Emaciated Cadaverous puppet designs ... Open hole ball joints should serve MOST of the Stop Motion needs. The high end Armature engineer elitiists sometimes look down at open hole joints. I could be classified as one of them but I am NOT! I say ... WHATEVER WORKS to CREATE the ANIMATION. The audience do not care how you got there.
I already understand, some into the TECHNICAL aspects of Armatures. Been there, done that. One can get preoccupied with it which is okay (armatures). Others though, if your goal is to do and create ANIMATION, you also have to focus on other aspects of a Stop Motion production (not just the armatures) ... but I digress.
I disqualified myself from this competition. Even though I've milled a number of sockets, I'm not convinced I got additional surface area. The mill and the ball need to be exactly exact and the same without any non-sameness for there to be full contact. I rely on an inner "open hole" as a backup contact surface.
What I *do* get from milling is a socket that wraps cleanly around the ball and has the extra strength of that metal. Also I can file away some of the end to allow freedom of movement in those emaciated joints.
Wait what ~ !!?
Hostess has gone under? Seriously??!! Wow, the end of an era truly!
I only gave a partial answer, leaving it open for others to talk about the disadvantages of the humble open hole ball joint and the advantages of milling and lathing. Dave, thanks for staying out - I could never have matched your high-tech terminology. I don't know tech talk like exactly exact and no non-sameness.