Mounting A Perfboard

[chuckfalcon]

Hi everyone, I have built my first circuit ever, straight from the schematic (look Ma, not kits).  I am wanting to mount it into a Hammond 1590BB box, but I don't really know how to do that.  None of my pots, jacks, or switches are board mounted, they mount to the enclosure and have wires coming off of them. 

Does anyone have any suggestions or ideas of how people normally do this?

[amptramp]

A lot of people attach hex standoffs to the board, place it where they want in the chassis then attach the standoffs with J-B Weld or some similar epoxy.  Once it sets up, the standoffs stay in place on the chassis and the board can be unscrewed from them for repair.

If you have large skirted knobs, you can attach standoffs via screws through the chassis that come to the outside under the knob where they will not be seen.

Other people use thick double-sided foam adhesive to attach the solder side of the board to the chassis.

Some people let the board float around on the inside protected by foam padding.  This is not really recommended since excessive movement can stress the connections and there is no guarantee that things will not move enough to permit an exposed circuit node to touch the chassis.

There are some chassis that have slots in the side where you slide the board into place.  They have end caps that hold the board in position.

I have one device in work now where the board has a connector on it and it is mounted to the bottom of the enclosure.  The top is removable and holds the controls.

There are a lot of gut shots on this forum.  Check out the pictures and something is bound to look like the right answer.

[GibsonGM]

All of the above, altho I do use the 'foam' method, with great results.  I make my pot leads short, and use stranded wire for all offboard stuff.   Then gently 'fit' my boards into the enclosure.  I use a piece of what some call "egg crate foam' from an old mattress pad, and cut to size/place on solder side of the board.

The rear cover presses this foam into the circuit board, holding it still. 

I bet the hell out of my stuff and have never had a short or other problem - it's in there too tightly to move around...knock on wood.  Your results certainly may vary, as will opinions about this.   I just like it because there are no holes to make for standoffs, and I don't trust that epoxying them inside the box will last.   

I think we all just read up on methods, and pick the one we like best

[scaramoustache]

I agree about epoxy. Brings only frustration in the long run in my experience. Foam on the other hand hasn't failed me yet.

[Transmogrifox]

Poor-man's standoff:


6-32 screw fits through these nicely.  Find a screw just long enough to fit the height of a bead, the width of the board and a nut on top.

The above mentioned techniques with epoxy or JBWeld apply equally. The last box I made I actually drilled the box, countersunk the holds and used countersink machine screws to make it flush on the outside of the box.  Then I had a nut on the inside of the box to hold the screw in place + plastic bead + board + nut.

YAWTSAC (Yet Another Way To Skin A Cat)

[digitalzombie]

Hi. New to building here.

Looking at OP's picture of the underside, is that really how you're supposed to make connections - by just laying tracks of solder?

[midwayfair]

Op: I make sure the perfboard is an appropriate size for the enclosure I'm using and the wires are the right length, and then use double-sided sticky tape to hold it in place on the back of the pots. Once the lid is on, it won't move. This requires some pre-planning.

digitalzombie, it looks like he just soldered every pad, but the actual connections are made with leads.

I do it just by soldering the junctions and not every pad in between, but both ways work well.

Some people use solder to make "traces" without using the component leads to make connections. Frequency Central did it that way, I know. That's harder to do and uses a ton of solder, but it's easier to swap out components if you need to.

There's no right way necessarily. There are ways that work and ways that don't. Do what's best for you.

[bloxstompboxes]

I currently use velcro cut to the match the size of the board and then stuck to the back of the pots. Allows easy removal for repair just like the thick 3M sticky tape. I am thinking of trying standoffs but me and liquid/gell adhesives don't usually work well together.

[greaser_au]

This thread may be useful: http://www.diystompboxes.com/smfforum/index.php?topic=109775.0
See my reply #19 with respect to epoxy. I'll add: surface preparation for using epoxy is a bit like preparing for paint. It won't stick very well on oily or glass-smooth surfaces.  Prepare everything before mixing, and work quickly, especially if using the 5-minute variety - once it starts to thicken up it's pretty much game over.

david

[karbomusic]

I agree about epoxy. Brings only frustration in the long run in my experience. Foam on the other hand hasn't failed me yet.

My first few were frustrating, now, they aren't coming off without muscle and a pair of pliers. For JB Weld we want, IIRC to rough it up with something like 30-80 grit sandpaper (box AND standoff), something smoother probably won't work as well as it seems like it would because the scratches created don't provide enough unique surface area to bond properly. I sometimes drill a tiny array of holes where the standoff goes, takes 2 minutes, lasts a proverbial lifetime.

I also found these tiny nylon washers that are just the right size. In other words they fit over the screw but tightly. This means that I slip the screw through the board and place the washer on the standoff side of the perf and now the screw is secured to the board but will never fall out which is extremely handy. It also serves as additional protection from a short as a safety measure because it keeps the standoff from contacting the bottom of the board.

I'll add: surface preparation for using epoxy is a bit like preparing for paint.

Absolutely, without preparing the surfaces, they'll fall off in short order. It's epoxy, not magic. it has to have something suitable to "grab" onto; JB Weld (the quick set) is rated at 2300 pounds per square inch and 500 degrees F if properly used IIRC. The slower setting version is 600 degrees and 3300 pounds if memory serves. 

Lastly, there is little need for four of them. I usually use two, and in some cases one because it holds so well if properly adhered. I have some 1/2" spacers I use to support the odd end of the board when using two. Works like a charm.

[duck_arse]

there is a different method to mount in this thread:

http://www.diystompboxes.com/smfforum/index.php?topic=106882.0

[Kipper4]

Personally I hot melt a piece of card to the underside of the perf and then hot melt that to the back of the pots.
Easy to remove should the need arise for repairs etc, then all that's needed is a new piece of card and voila

[PBE6]

I use one or two layers of duct tape on the back of the board with some wrap around on the sides, then use the double-side sticky tape to adhere the tape to the enclosure (or the pots if room is tight). The duct tape comes off the board relatively easily for repairs/mods, and the wrap around holds it in place even after a few removals.

[LightSoundGeometry]

blu tak 

[PRR]

> make connections - by just laying tracks of solder?

His solder is too thick to be sure what was done; but you can't "lay tracks" that thick without it all running together as a sea of solder.

Usually you put a lead through, bend it down to the board. Do another lead and solder the intersection. Small tight systems you can often do the whole thing just with the part leads. Larger or more tangled systems will want some jumper wires to get from here to there where there's no parts to contribute lead-length.