Recently I have been prototying various ideas with small modules from ebay and other sources. The problem is that the modules are random sizes (but usually under 2"x2") and I sometimes need to access one side or the other of the module with a multimeter or scope probe. Also there may be a need for bypass or decoupling capacitors, etc. between modules.

It is very tempting to just lash these things together rats-nest style but that is fraught with dodgy connections, noise, etc. So I was wondering if anyone has come up with an effective alternative. Just screwing them down to a board is OK until you have to access the underside. I keep dreaming up fancy clamping arrangements but they generally would take too long to fabricate.

So has anyone got a neat solution to this problem?

 

hi Chris,
This link may inspire some idea's.

https://www.google.co.uk/search?q=pcb+board+clamps&client=firefox-a&hs=TQm&rls=org.mozilla:en-USfficial&channel=sb&tbm=isch&imgil=XuxTxfU_YPWZ4M%253A%253Bhttps%253A%252F%252Fencrypted-tbn3.gstatic.com%252Fimages%253Fq%253Dtbn%253AANd9GcTMH4dqR0vGu4f4tfrEaml7byPBtU4FaWG17R5rPcCwKvqN2saa%253B401%253B168%253BtNHzLbK683AHNM%253Bhttp%25253A%25252F%25252Fwww.harwin.com%25252Fcatalogue%25252Ffeatured%25252Frfi_shield_clips.html&source=iu&usg=__Hg8BDgaDKURDkagA3uWwaXW2VjI%3D&sa=X&ei=CVkUU9TqJcaShQebloDIBw&ved=0CF8Q9QEwBA&biw=1369&bih=885#facrc=_&imgdii=_&imgrc=XuxTxfU_YPWZ4M%253A%3BtNHzLbK683AHNM%3Bhttp%253A%252F%252Fwww.harwin.com%252Fimages%252Ffeatured%252FEZ-BoardWare_Shield_Clips_Sept_13.jpg%3Bhttp%253A%252F%252Fwww.harwin.com%252Fcatalogue%252Ffeatured%252Frfi_shield_clips.html%3B401%3B168

Eric

 

Thanks Eric, the thing is I might have 3 or 4 of these boards connected together (e.g. SD Card, FTDI, processor, temp. sensor) and they are all different sizes, some have tracks and components very close to the edge, some have connectors at either end. I would like to hold them in a fairly consistent physical arrangement rather than having separate clamps where they can move around.

 

hi,
Perhaps some of this miniature peg board with rotatable eccentric pegs, to grip the board edges could be a possible solution.

https://www.google.co.uk/search?q=m...are-Peg-Board-for-Hama-MINI-Beads-593;599;600

 

This is a permanent mount for specific size that I've used.

I believe it could be modified easily.

Cut it length wise and mount the 2 pieces to a back board of some sort.

Board would have to be unsnapped for probing the back.

http://www.datatranlabs.com/product_p/z1017.htm

 

I have a bunch of these x-acto clamps. About $3 per pair so dirt cheap if you can find them. Discontinued recently by x-acto.

http://www.widgetsupply.com/product/BER34.html

 

Those tiny modules are sometimes not much bigger than a fingernail. I just hot-melt glue them in place. It holds securely as long as you like, but they can still be "broken free" to re-use the boards later.

 

Those x-acto clamps look good, I've requested a price for UK shipping, which I suspect will be a lot more than the cost of the product.

The hot-melt glue idea also sounds worth trying.

 

These http://www.miteebite.com/products/fixture_clamp_e.html may work, but they aren't cheap. http://www.fastenal.com/web/product...pcode=&filterByStore=&filterByVendingMachine=

 

How about alligator/crocodile clips. Take a piece of wood or plastic and drill a series of holes, that fit the barrel of the clamps, in a straight line. Leaving 1/8" or so between holes. With the clamps pointing upward and clipping the edge of the board, you would have access to both sides. And the row of holes would allow them to be moved to fit any size board/module. Kind of like a multiple "helping hands".

 

Modulules often come with 0.1" spaced terminals, great for solder or solderless breadboards(I take mine with solder). When I want to remove sections I use female pin headers to make sockets.

I keep stock in 40 pin wide units and just cut off the length I need.

Friction is all that's needed to keep things in place.

 

If you're going to be powering up the boards while in the clips, metal alligator clips will be pretty risky. You might consider using wooden clothespins instead; they are dirt cheap and should be available everywhere.

 

Thanks guys, it's a shame those off-set cap-screw clamps are so expensive I can see that they would have a lot of uses, although I guess it wouldn't be too hard to make a batch (if only I had the time).

I have been hatching a plan that combines a few ideas suggested here. My current thinking is a wooden board with a number of square wooden pegs mounted vertically. Since most of the circuit boards I am using have some kind of pin header, I am thinking (as ErnieM suggests) of soldering receptacles to small pieces of strip board and then clipping the strip board with clothes pegs(pins) or bulldog clips to the vertical pegs on the board so the board would be vertical with both sides accessible. A dab of hot-melt at the other end of the circuit board on the base board would stop them wobbling around.

I'll let you know how I get on.

 

So here is what I came up with. It's an MDF/wood box with a length of DIN rail mounted on the back. Some square pegs are attached to the DIN rail and boards can be held to these pegs with bulldog clips. I have also put some connectors on the rail so I can hook-up power/ground etc as required.

If needs-be a blob of hot melt could be used to hold the free end of the circuit board to the base.

 

Ok, I was trying to help with a minimalist approach. I would have given a completely different answer if I know overkill was an option.

 

the previous image link also turned up this thing, which i think I also might buy now

https://www.google.co.uk/search?q=p...duct.php%2F507%2F0%2Fpcb_board_holder;300;300

 

You could use a Helping Hand alligator clip holder for soldering and stuff.

http://www.adafruit.com/products/291?gclid=CNHjn-XZkL0CFSqXOgod_0QAkQ

I also found small wooden "clothes line" clips that can substitute for metal clips when holding circuit boards so they won't short out.

Stiff solid wires can be used to interface a circuit to a breadboard too.