Roll Pins

[jmccartney]

   
I was curious to get opinions on alternative fasteners. I was thinking this morning (dangerous) about when I built my AR-15 and how some components used "roll pins". They were horribly annoying because they tend to bend or deform.

I don't see any examples of PLA roll pins on thingiverse. Is this because its not possible to do? In my head they seem like they could work and would be better than "snaps" and tabs for certain things.

I am not sure "roll pin" is a international term. This link has what I am talking about http://en.wikipedia.org/wiki/Spring_pin towards the bottom under "slotted spring pin".

(FYI I have also used the "coiled spring pin" depicted on the wiki page, they are much easier and reliable to work with but probably not practical for printing)

[jmccartney]

Its not that I have any issue with using screws and nuts, but it feels WAY overkill a lot of times. If I could say replace half the screws with 5mm roll pins I think that would be great. (I like to use my little hammer and a punch, something satisfying using a hammer to lightly tap things)

[steamboat]

(05-08-2014 01:44 AM)jmccartney Wrote:  If I could say replace half the screws with 5mm roll pins I think that would be great.

I agree! All this need an exact counterpart in diameter. Not to big and not to small. This might be a problem?!

The M3 screw in a printed plastic hole is the first step in the right direction and is more failure tolerant. I just used M2 screws in Plastik also quite stable enough for most things - but M2 makes me nervous ;-)

[jmccartney]

    I published a roll pin on thingiverse. I think M3 roll pins might be out of the realm of homemade printers. I tried working with a dimension that would print @ .25mm and I have actually printed all my pins at this, but I ended up having to move the OD to a odd dimension since it was .1mm too large to easily fit. I am going to make some larger sizes that should print fine on any printer.

http://www.thingiverse.com/thing:324816

[steamboat]

(05-10-2014 12:49 AM)jmccartney Wrote:  I am going to make some larger sizes that should print fine on any printer.

The poit is to get it flexible enough - so the wall thickness has to be small in correspondance to the outer diameter. If the wall thickness is given by the material/printer so is the related minimum pin diameter...

What about a rectangular "shim pin" or its round counterpart the "conical pin"? Ok it'S always depends of what you want to mount/fix...

But all this should be a key discussion in the 3D printer scene!