Number of pins? & Point of contact?

[Yogi patel]

Hello.. I am confused in two questions.
First one is i am designing 1 pin shaped which can mould the free form surface. i am confused in different type of shapes pin like circle, square, triangle..etc.. My question is if i am moulding a free form surface by these shape of pins which shape will highest & equal type of point of contact. & when i revolve the pin at 30 degree the point of contact will be the same as 90 degree?
Second question is there is one plate of 600*600 mm where i will be putting my pins with some distance.. So how much distance should i put the pins that i can revolve the pins at 30 degree & put as much as less pins?

 

[berkeman]

Welcome to the PF, Yogi.

Can you attach a sketch or picture of what you are trying to do? So far your questions are not clear to me. When you say "mould", do you mean like injection molding of shapes? Are you asking about how to release different shapes from a mold?

Or are you asking about attaching pins to various shapes to provide support when sitting on flat surfaces maybe?

 

[Yogi patel]

I am designing like this. you can see the pins are moulding a free form surface. In this example you can see there is circular Pin tip. The PIN TIP is also rotating with 30 degree of rotation. My question is which type of PIN TIP i should use for best point of contact like any circular type pins, any square type pins or any triangular type pins etc..The point of contact should be the same in 30 degree or 90 degree??

 

[berkeman]

Interesting! I hadn't seen those before. What kind of tips do the Adapa folks use?

https://adapa.dk/wp-content/uploads/2019/03/Adapa-Product-Brochure.pdf

 

[Yogi patel]

Adapa is not using any pins because its moulding in concrete & plastic in liquid form, so its just doing with help of actuators only. but in my case I am using steel pins to mould aluminium sheet.

 

[Baluncore]

Decades ago, I looked at the possibility of moulds made from a bed of close packed hexagonal pins, covered by a sheet of rubber, all held down by a vacuum. The aim was to select, place and adjust the pins automatically from a numerical definition of the surface.

 

[JBA]

How do you plan to get the aluminum sheet to conform to the pin set's profile contours?