Why do IC pins bend outward? (QYAWABWA)

[thelonious]

My head is full of dumb questions about things that just don't matter, but I'm still curious about. You know what I mean - Questions You've Always Wondered About But Won't Ask. In the interest of brevity and fun pronunciation attempts, I'm dubbing these QYAWABWA.

So here's QYAWABWA #1: Why do IC pins bend outward? In order to socket them, you've got to bend all the pins inward, but because your fingers are round, they never %$%&* bend evenly. I'm assuming they are manufactured to bend outward for a reason other than to drive DIY people to drink. Anyone know the answer?

[deadastronaut]

so they can lock in a socket..

i push down on them on a flat surface to straighten a little , but still leave enough 'spring' to hold into a socket

[armdnrdy]

1. So that you will ruin the IC and have to purchase another one when you try to bend the pins inward to where they will fit in the standard board holes or socket. It's a corporate plot! 

2. Because life is too easy? One does need a bit of frustration to be well balanced.

3. Because if they weren't bent outward....you would have no reason to start this thread?

4. So they don't fall over as easily when they get off of the bar stool?

5. So that when some stupid person puts them in an envelope on a piece of ESD foam, and they get smashed, the pins lay flat (like a dead bugs legs) instead of poking through the envelope where they could be a hazard for the mail carrier.

That's all that comes to mind....I'm sure it's one of these. 

[TGP39]

Because IC's wobble, but they don't fall down.   Seriously, I've wondered the same thing. I just use my normally closed tweezers to bend the whole line of pins in unison. Getting better at it each time. I also fit the chip into the socket before I solder the socket only. Hope this helps.

[armdnrdy]

There was a thread in the not so distant past, which showed a tool that is specifically for bending IC pins to where they fit.

It almost doesn't make sense for most applications....the manufacturer installs the pins bent outward...then you have to bend the pins inward before you can install it!

I'm sure the outward bend is for a production machine that bend the pins in, inserts the IC, and the spring tension of the pins holds the IC in place for soldering.

[thelonious]

i push down on them on a flat surface to straighten a little , but still leave enough 'spring' to hold into a socket

I just use my normally closed tweezers to bend the whole line of pins in unison.

Ah man, why did I never think of either of these things??

so they can lock in a socket..

I'm sure the outward bend is for a production machine that bend the pins in, inserts the IC, and the spring tension of the pins holds the IC in place for soldering.

That has to be the "real" answer, but I'm going with the corporate conspiracy one you mentioned.

[armdnrdy]

Here's one of the IC pin straighteners:

https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&pa=99363&productId=99363

[duck_arse]

if the pins weren't splayed, the ic's wouldn't fit in the plastic, anti-static shipping tubes.

[amptramp]

Here is a standard IC insertion tool:

http://www.zorocanada.com/g/00140933/k-G4799383?gclid=CO2civHlxb4CFeY-MgodWH8AnA

You push the IC upward into it, setting the pins at right angels to the body (in other words, vertical).  Then you can just inject them into the boards or sockets.  Splaying them out prevents them from going inward which would make this tool unusable.

[armdnrdy]

Here is a standard IC insertion tool:

http://www.zorocanada.com/g/00140933/k-G4799383?gclid=CO2civHlxb4CFeY-MgodWH8AnA

Your link is for an extraction tool for extracting DIP/IC chips from sockets.
Read the product description at the bottom. 

[peterg]

I'm assuming they are manufactured to bend outward for a reason other than to drive DIY people to drink. Anyone know the answer?

that's the only reason I need!

[PRR]

I think the insertion tool is the middle tool in this pic:



The other one "can" do insertion or extraction (the description is incomplete), but is more expensive, so you would not use it just for insertion.

They splay because they will never stay vertical, and if they went both ways it would be awkward. By splaying out, they can be jammed into a precision C-channel, stay by friction, go right into the holes. On PCB, when you pull the tool away, the residual splay tends to keep the DIPs in the PCB.

[CodeMonk]

From Grainger :
http://www.grainger.com/search?searchQuery=ic+insertion+tool

Or from McMaster Carr
http://www.mcmaster.com/#ic-(integrated-circuit)-insert-tools/=s44she

I can't remember where I got mine

[duck_arse]

far left of PRR's pic, up top of handle, is a pin straightener. shove the IC in, pull it out, pins right-angled. the fourth in line also has a straightener, but used diffrntly. #3 was the bog standard insertion tool the girls used to use on the line (all the while talking to their sister), the second one is the deluxe extractor, with the grabbing hooked legs, will also straighten and insert.

the last in line is the one that lives in the production tech's drawer, they don't even know what it is for. this is probably all in those links, but I'm lazy that way.

ohh, it pulls ic's from sockets, if any prod techs are reading.

[R.G.]

They are spread a few degrees so they can be held in an insertion tool to insert into a PCB footprint, then spring back out and hold the IC in the PCB spot without the IC dropping out from gentle handling. For instance, if you do the insertion tool to put them into a PCB, you can turn the board over and solder the pins without the IC falling out.

It's nothing to do with sockets. For inserting into a socket, you need to form the leads to the correct 0.3" wide pitch (for DIPs) and insert them. A PCB insertion tool can be used for socket insertion to get the leads lined up over the socket holes, though.

[Jdansti]

>It's nothing to do with sockets. For inserting into a socket, you need to form the leads to the correct 0.3" wide pitch (for DIPs) and insert them.

I do this and line up one side first, but only insert them partially.  If any of the pins on the other side are too wide, I use a small flat blade screw driver to gently bend the pin(s) in as I insert them.

[R.G.]

Yeah, that's what I do. I have an insertion tool somewhere, but I'm too lazy to go look for it. A better tool is the end of a 6" stainless-steel machinist's rule. But I broke my machinist's rule and haven't bought another.

[davent]

Okay... how do you bust a 6" SS rule? There's got to be a story, very nasty IC legs.
dave