Out of interest, ignoring the purple rubber bits, what materials do you think this hanger is made out of?
Link
The white plastic is extremely waxy to the touch.
The hook section at the top rotates very easily.
> I think you should allow for a cubic volume about 3x3x3m btwn. the two 10mm bars, at their ends.
Confused. Do you mean 18 cubic meters of space at the ends of the two bars... ?
To try to simplify the original problem, I think part "A" (the Stiff to Turn" aspect) should be fairly simple to...
> Take apart kayak paddles do this. Sort of. At least aspects of if.
Interesting. I have only ever seen fixed kayak paddles. Does this only apply to some variety of collapsible paddles?
Short of going to a canoe retailer can you say any more about this or where I could find out more?
3DDave - The point about the "Spin Mode" is simply that it needs to turn very easily but TEND to stop in at compass bearing (or 180 degrees from it)
To get clear, the device will not pay any attention whatsoever to *actual* compass bearings - I only used them as random examples and to avoid...
Hello
I have a design challenge for you.
I need to design a joint between 2 round bars of plastic. It is part of a consumer product.
- Diameter of both bars: 10mm
- Material: injection moulded plastic (probably LDPE)
To keep costs down there should be no metal or other materials - just the...
Finally getting there... with a little help from the Chartered Institute of Ergonomics, I have finally discovered that for pinching between first and index finger (which is what will be required by our new product):
1). 95% of women should be able to pinch with 62+ Newtons (my 66 Newtons above...
1. Excellent! OK I now have some thumb-finger forces data
Details:
I managed to download the "MIL-STD-1472, Human Engineering" PDF from here:
http://everyspec.com/MIL-STD/MIL-STD-1400-1499/MIL-STD-1472F_208/
On page 94 the "THUMB-FINGER GRIP (PALMER)" seems to be 60 Newtons of momentary hold...
Hello
I am designing product that is similar to a clothespin /cloths-peg. i.e. It involves some jaws that need to be opened by a user with one hand.
I need to know:
a) What is the maximum ergonomic span between thumb and 1st (or 2nd) fingers?
b) What is the maximum acceptable for between thumb...
This sounds intriguing. I don't quite understand. Do you mean one V inside the other (i.e. of shorter length) or one V behind the other? (i.e. further away from the viewer in my above diagram)
OP
dhengr:
Humble apologies again for my order of magnitude typo.
Exact diameter is not under my control. If the diameter of the horizontal bar was known like would be easier(!)
However in practice, depending on exactly where the the product that I am designing will be used, it will need to hook...
> What are your post-hanging motion requirements?
> Something more than just aligning the V to the bar?
If the hook gets brushed lightly e.g. by hand, it would need to swing about a bit but again come to rest hanging (to within c.1.5 degrees) parallel to the horizontal bar.
> Observe clothes...
OK let me try and get my head around this.
1. Shallow 'compass bearing' angles
In the starting condition, if the top of the hook - i.e. the plastic (inverted) V - has been rotated horizontally to be aligned at a pretty extreme compass bearing (e.g. say 20 degrees) away from that of horizontal...
robyengIT - I had a quick look at your equations and they seem to be more about pipes joining each other at strange angles. Whereas whatever it is that I need friction will clearly be a core component in the calculations.
Unless someone can tell me otherwise, I fear that running what will...
> Ship69, if there is a chance that the load could swing side to side, you may not want the
> shallowest angle. If too shallow, the load may not recenter itself or may fall off.
No - not really, its movement will be heavily dampened (by air resistance), and so multiple swings back and forth...
I agree that 45 degrees would work. However it does seems unnecessarily extreme. Like I say, I am after the widest angle that will still be likely to work.
I am a humble novice, but it's starting to sound like there are no rules of thumb or sensible guesses and that the engineering is too...
> Make the included angle 120 degrees.
Sounds reasonable...
I'm slightly confused about the rationale for 120 though.
How far will the vertical axis rotation need to proceed in order to get the your ramp out force?
The plastic V guide is smooth - probably waxy poly ethylene.
The metal bar will be a fixed object - normally polished metal. (Although it may possibly be smooth painted/varnished wood.)
The V shaped plastic guide is the top section of a hook design and is held in place purely by gravity.
