an alternative to board standoffs

[gaussmarkov]

two thoughts came together today in an idea that IMHO has legs.     that means somebody has already thought of it.   but i haven't seen it yet so i'm offering it up.

i have been thinking about how to keep circuit boards in enclosures using the clever engineering with cardboard that i see in lots of boxed stuff.  and i was also thinking about splitting one circuit across two boards mounted side-by-side.  today i worked up a prototype for doing both.  here's couple of pics with our new camera (that's really the reason i'm posting--we have a new camera that can take closeups ).





i cut and folded a sheet of overhead transparency.  i was going to use cardboard or even card stock.  but you can see better what i am up to this way.  once placed in the enclosure, this holder cannot come apart and the board is secure.

i used .1" between the corner folds.  one could be more generous.  if you don't have a board that fills the width and depth you can make some more corners to make up the distance.  this can also work for boards that lie horizontally, to keep them away from the enclosure.  it's possible to cut gaps for wires if  necessary.  and you can place the notches for the board along the sides as well, using triangle shapes.

concerning these particular pictures:  i hope that you can see the notches for the second board, to the right of the board that's in place.  and the bottom corners of this board are nibbled off because of the rim-like seal on the lid.  actually, the whole things goes in with those corners up and out.  even with the nibbles, the square notches grip enough of the board to hold it.

all of this is for insurance only.  i find that solid hookup wire, pots, jacks, and all holds things pretty secure.  but sometimes it's good to be sure.

so what do you think?

[jimbob]

It looks like a lot of work. I have tried all kids of ways. The best I like is the white standoffs that go through a hole in the board- except that Im not fond of the price and unavailability- I can only find those at smallbear or mouser.-in other words i have to order them when Id rather find something like that at Walmart or something local. I use the Boss style of aiming the solder side of the board towards the place I close it with and use a protective layer of something like trasparent plastic or even packing material  trpe stuff in the shape of the back place then seal it.

Great thinking though- but there has to be an easier and more inexpesive way still.

[gaussmarkov]

thanks for the feedback jimbob.  maybe this is too much work.   and it's dirt cheap!   you can make it with the transparent plastic that you are already using.

i was surprised to hear you say its a lot of work though.  i just folded and cut a piece of plastic!    here's an illustration that shows my layout and some construction.



it's hard to let go of one of your own.  last post on this one. 

[lovekraft0]

Very clever - I'll definitely add that one to my bag o' tricks, thanks!!

[AWelti]

Your idea is Great,
How about a tiny tweak to make it a tiny bit simpler...  Toss the green cut-outs and fold 45 degrees...



I think your idea is simpler than figuring out where to drill holes for standoffs in the box and PCB.  You could probably just use a hole punch instead of cutting little rectangles and still hold the PCB  well enough.

[gaussmarkov]

Your idea is Great,
How about a tiny tweak to make it a tiny bit simpler... 

yes, good thought!  that is actually what i did at first and that will often work well.  in my case, i had to nibble some of the corners of the pcb away to accomodate the lid so i wanted more.  i lke the idea of making the board fill as much space as it can as a simple way to make it secure.  also i wanted to see whether the more finicky approach that i took would still work.  but i totally agree with you.  your simpler approach is more attractive precisely because it is easier.  thanks!

Very clever - I'll definitely add that one to my bag o' tricks, thanks!!

thanks, man.  i hope it will be useful one day.   

[gaussmarkov]

Your idea is Great,
How about a tiny tweak to make it a tiny bit simpler... 

yes, good thought!  that is actually what i did at first and that will often work well.  in my case, i had to nibble some of the corners of the pcb away to accomodate the lid so i wanted more.  i lke the idea of making the board fill as much space as it can as a simple way to make it secure.  also i wanted to see whether the more finicky approach that i took would still work.  but i totally agree with you.  your simpler approach is more attractive precisely because it is easier.  thanks!

hmmm.  it just occurred to me after writing this that i must be crushing the plastic holder if i have to nibble off those corners to close the box.  that makes the diagonal approach the only way to go for those corners in my setup.  awesome, AWelti.  thanks again!

edit:  on third thought  i could also completely remove the plastic like you do for the diagonal version.  then those corners wouldn't be sticking out.  imagining spatial things (as opposed to actually constructing them) takes some talent!