|norman valentine||26/06/2021 10:51:19|
|280 forum posts|
|2242 forum posts|
Is this wonderful vice design actually based on fractal geometry?
There is a degree of self-replication in the jaws. What was the state of fractal science at the date of the patent? Mandelbrot came along later, I think.
|Clive Foster||26/06/2021 11:48:01|
|2817 forum posts|
Fractal refers to replication of identical elements in ever smaller sizes starting from a single base shape.
All the pivoting arrangements of the vice segments are the same shape. Each little segment moves independently, as each larger segment does, so the vice jaws are true fractal! 2 to the 4th power.
Mandelbrot basically formalised the mathematics to establish the general solution and demonstrate the capability of infinite expansion.
Infinite replication of ever smaller elements doesn't actually have to refer to identical shapes but the maths is more than a little challenging rendering the concept pretty much impractical in an analytical sense.
|Calum Galleitch||26/06/2021 14:38:50|
96 forum posts
The term 'fractal' was first used by mathematicians to explore the idea that between the common concepts of one, two, and three dimensional spaces, there could be other, in-between fractal dimensions. This gives rise to things like shapes with infinite perimeters yet finite area, or bounded lines of infinite length. Self-similarity isn't a necessary condition, but it's easy to come up with rules to create fractals that are self-similar and mathematically tractable. Discovering non-similar fractals is a trickier enterprise. It turns out that generalising the concept of 'fractal' to a usable, precise mathematical definition isn't especially useful, so nowadays fractal is more of "I know it when I see it" term.
|Jon Lawes||26/06/2021 14:52:41|
636 forum posts
What a fantastic piece of equipment, whatever it is called. I wish they still sold them as I haven't a hope in hell of making one!
|Jeff Dayman||26/06/2021 14:55:07|
|2166 forum posts|
Does it matter what it is called? It's a clever design, and well made. Could be very useful in some circumstances.
|Frances IoM||26/06/2021 14:57:07|
|1154 forum posts|
|looks an ideal task to make use of 'parametric instantiation' - (see a prev thread complaining such a term had no place in Model Engineering) followed by CNC machining|
|Nigel Bennett||26/06/2021 14:59:36|
413 forum posts
One thing that did please me in his very interesting YouTube video - his use of Sheffield-made Eclipse Vee blocks when drilling a hole at one point.
Amazing vice, though - and a lot of precision needed to make it in 1913. What would it cost to make it today?
6010 forum posts
Certainly something to consider for 3D printing - to be lazy about it.
Will one of the CAD gurus have the design out before I can finish typing?
|Peter Greene||23/07/2021 19:28:33|
|272 forum posts|
This 3D Printed Version at Thingiverse might be of interest.
|Rod Renshaw||23/07/2021 19:54:21|
|301 forum posts|
I wonder if they could be made today using CNC setups to keep the cost down compared to the hand fitting methods presumably needed for the original. Potentially small market though I suppose.
The Swedish firm SEVO make or made a much simpler version which seems to work reasonably well.
|Brian G||23/07/2021 20:27:04|
|777 forum posts|
There is another vice rebuild on YouTube featuring similarly adaptive gripping, this Ampogrip vice that uses ball bearings as a hydraulic fluid.
1021 forum posts
For light work you could print this one from Thingiverse
Edit: Oops, missed Peter's post above.
Edited By Journeyman on 24/07/2021 08:59:16
4689 forum posts
Looks brilliant in theory but with so many moving parts it's going to be a bit wonky after a bit of use
|David Colwill||24/07/2021 09:46:37|
|763 forum posts|
What does the "B" in Benoir B Mandlebrot stand for?
Answer Benoir B Mandlebrot.
I'll get me hat!
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