A drop of ? to hold wires to board

[Cicada]

Hi

Question
What is ? below.

I want to put a drop of ? on my PCB to hold-down/secure 4 very this wires that I will soldered to pads on a 0.5mm pitch connector. Super glue is not a solution. Its a mess and it can damage the PCB surface and tracks if you decide to remove the wires.

? makes only a small silicon/rubber like blob on the board that secures the wires to the PCB very well but when you remove it it does not damage the PCB.

? Is readily available from most big electronics distributors.

Thank you.

[mikeselectricstuff]

UV cure glue - sold for things like fishing lures. Sets in a second or two with UV flashlight.
http://www.ebay.co.uk/itm/5-Second-Fix-UV-Light-Cure-Welding-Compound-Glue-Pen-Glass-Plastic-Repair-/122132871974?var=&hash=item1c6fafbb26:m:mjy1w4Pv303D22j4PvnRmBg

[NivagSwerdna]

UV cure glue

This looks like fun stuff. But how does it compare to superglue? I remember pictures of modchipped games consoles with beautiful kynar wiring...

Cableporn

[Cicada]

Hi

I have used superglue in the past to fasten wires to a board. From what I remember it makes quite a mess. It flows easily so even a drop just spread all over. It also looks bad it makes a big white stain that almost look like some sort of crystallization formation.

I cannot remember if I have ever tried to remove a wire fastened with superglue but my guess is that it will at least possibly remove the solder resist with it. If there are thin tracks beneath even the tracks. Not that one necessarily plan to remove a wire afterwards.

I would just like to avoid superglue. I have being thinking about something like clear potting compound. I have seen a EEVBLOG tear down video where Dave used a screwdriver to pierce a clear potting compound on a high voltage board to reach a tuning pot or something. It closes up nicely after the screwdriver was removed. That look like a sturdy enough material to fasten a couple of wire with a drop. 

[drummerdimitri]

What about some hot glue? It should be good enough for your application. UV glue is also a great idea I've used it on a board once to secure a tiny wire to a PCB with great result.

[cowana]

A drop silicone adhesive such as Dow Corning 3145 would be the best option.

http://www.dowcorning.com/DataFiles/090276fe801f97f8.pdf

[CJay]

Glass bond glue, it's the same as the UV stuff Mike mentioned IIRC, there's also superglue gel which is designed for wiring mods, TakPak I think they market it as, a two part pack with activator and glue.

Both cure really quickly, I think the UV stuff would be easier to remove with less board damage...

If you decide on a silicone make sure it's a neutral cure or you might find yourself with a board that's gone green, plus it takes quite a bit longer to cure than the other two.

Hot Snot, it's cheap but it's difficult to make it neat and of course will fall off if the board gets too cold or will re-melt if it gets too hot.

[Ian.M]

Bostik Impact Adhesive or similar - cures by solvent evaporation, unlike silicone it doesn't go bad in the tube so easily, dries to a rubbery consistancy so the wires can be ripped up with minimal risk of board damage.

[dimkasta]

You can try an adhesive tie wrap mount like those below. Mount it with double side tape

http://www.panduit.com/heiler/ProductImages/wABMT-a-c20-o.jpg
https://gp1.wpc.edgecastcdn.net/00AC62/photos/151-31201_US_PROD01_sm.jpg

If you cannot find something small enough, perhaps you can super glue a hollow spacer and pass the cables through it

[ajb]

I have used superglue in the past to fasten wires to a board. From what I remember it makes quite a mess. It flows easily so even a drop just spread all over. It also looks bad it makes a big white stain that almost look like some sort of crystallization formation.

Low viscosity superglues will have these problems, but you can get CA glues in thicker viscosities, up to a gel consistency.  The thicker formulations cure more slowly and so tend not to leave white clouds in the vicinity.  A good hobby store will likely have three or four different formulations to choose from.

That said, if you want something removable, superglue is probably not the best choice.

[chickenHeadKnob]

If I want to affix something with a flexible rubbery type of gap filling glue I use the stuff that is called "shoe goo" or "Amazing Goop". Widely available in north America, I think they are the same just different brands. They appear like clear greasy silicone rubber out of the tube and contain perchloroethylene  as a solvent which evapourates. Easy to apply and control, you can use a toothpick to direct tiny blobs where needed. The perc solvent does attack plastics and rubber and this can be to an advantage if gluing layers of a sneaker. On a pcb so little will go into the board that I don't think it matters

[PointyOintment]

Where I live, Home Depot, probably other hardware stores, and even Safeway (a grocery store) carry this gel superglue among other options. I've carried it in my backpack for years. It's very good for closing cuts, sealing torn fingernails, etc., because it cures within a few minutes and doesn't flow everywhere. It would hold wires to a PCB, and wouldn't make a mess, but it would be hard to remove cleanly. I did try using in place of solder to connect wires to a PCB once (because my soldering iron was packed away, I think). That didn't work.

[DTJ]

Use cheap clear nail varnish or even green stuff to be fancy. $2 per bottle.

If you leave the lid off the bottle for a few hours the solvent evaporates thickening  up to your preferred consistency.

[xrunner]

UV cure glue - sold for things like fishing lures. Sets in a second or two with UV flashlight.
http://www.ebay.co.uk/itm/5-Second-Fix-UV-Light-Cure-Welding-Compound-Glue-Pen-Glass-Plastic-Repair-/122132871974?var=&hash=item1c6fafbb26:m:mjy1w4Pv303D22j4PvnRmBg

Oh how have I missed this? I gotta have that going to Ebay right now! 

[KL27x]

Swear the OP read like a jeopardy question for "what is hot glue?"

Usually, the esthetics and strength doesn't matter much. You're not gonna see it or care if it falls off, later. It just has to hold together long enough to get the boards back in the enclosure, lol. After that, the wires aren't going to need the strain relief, anymore. But FWIW, if you find a good hot glue, it can be essentially permanent barring solvents or obviously high temp. And if it doesn't look neat enough the first time, drop of alcohol, pull it off, and do it again.

I have one of the adjustable temp guns; I keep the temp where I can touch the bead without burning myself. It can remain on, constantly, without burning the glue.

[P90]

yellow-ish high strength hot glue.

[KL27x]

Hot glue can be very neat, too. Where the esthetics matter, I am pretty accomplished at molding hot snot with packing tape to get smooth contours and trimming with a razor sharp knife (sticky side of the tape goes on the glue, if you want it to peel off!). You have limited window to get it right, but it's probably the most amazing stuff on the planet for prototyping, repairs, and the like. For certain things it can be made very, very permanent.   

[nikonoid]

At work we use a glue called E6000. It is great that it grips to most smooth and porous surfaces. It is clear, so looks good. When dried, it behaves like a clear rubber, so you can always remove it without damaging anything. It is also temperature and water resistant.


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[P90]

At work we use a glue called E6000. It is great that it grips to most smooth and porous surfaces. It is clear, so looks good. When dried, it behaves like a clear rubber, so you can always remove it without damaging anything. It is also temperature and water resistant.


Sent from my iPhone using Tapatalk

that stuff contains Tetrachloroethylene, not the most toxic chemical, but still, I'd stick with hot glue...

[vk6zgo]

Back in the late '70s/early '80s I attended a course in "High Reliability Hand Soldering".

Among many other things, we were introduced to an adhesive which was specially designed to attach  wires to a PCB.
It worked extremely well, with no grotty "mess" like that from "Super Glue".
From memory, it was marketed by Pace, but it might have been some other supplier.

Maybe because there is less need to make PCB modifications now, (or perhaps because it contained something nasty), this product seems to have vanished from the market.

[P90]

Back in the late '70s/early '80s I attended a course in "High Reliability Hand Soldering".

Among many other things, we were introduced to an adhesive which was specially designed to attach  wires to a PCB.
It worked extremely well, with no grotty "mess" like that from "Super Glue".
From memory, it was marketed by Pace, but it might have been some other supplier.

Maybe because there is less need to make PCB modifications now, (or perhaps because it contained something nasty), this product seems to have vanished from the market.

I seem to recall we used some sort of yellow contact cement in the old days...

[SeanB]

I would go with the UV cure glue, as it is available with decent price, and will cure nicely with UV light in a few seconds, so you can align the wires before hitting the torch to it. The silicones are good, providing you have the time for the reaction to complete and enough oxygen in the silicone to polymerise it.

As an alternative 5 minute epoxy is good, reasonably fast and can be done with a pack of bamboo skewers to grab a drop out of a small dollop of each type, and then mix on a small piece of waxed paper. Dispose of each skewer after a single use, and you will need 2 per batch, one per blob of epoxy mix, and then use only the one to mix them and apply the drop before it cures. Fastest cure I find is the Pratley quickset steel or white, it will cure fast, and the clear is the slowest.

I really would not use hot melt glue, many of the formulations they are made from have very poor long term properties, they tend to react chemically with time and temperature, forming either a conductive film on the surface or corroding the copper wires and board. The yellow contact adhesive does the same, though it also likes to do both at the same time, and the solvents in it will destroy electrolytic capacitors by damaging the rubber seal and allowing the capacitor to lose electrolyte faster.

Superglue I used a lot to bond wires and fix traces, just use the gel types, and simply use masking tape ( painters tape in the USA) and cut paper masks to mask off most of the board so the bloom it creates ( evaporating light components of the glue) is easy to clean afterwards. Using the activator spray in areas with low humidity also helps, but here at the coast I am a lot more concerned with keeping it in the fridge so it does not cure in the bottle, than to really use an activator on it.

[Ian.M]

The glue to avoid at all costs is that yellow foaming glue that sets fairly hard. It used to be used in a lot of consumer electronics, and was an absolute disaster - worse to remove than well bonded silicone, and tended to become conductive with heat and age to the point that you'd get runaway carbonisation if it bridged two conductors with a high enough voltage difference.  Its breakdown products could also attack copper . . . .

If you see it and its gone brown you know you are in for a PITA of a job trying to remove enough of it to halt the damage.

[KE5FX]

I like to use Devcon 5-minute epoxy for this sort of thing.  It sets quickly, dries clear, and doesn't promote corrosion.  It's also easy to remove with a heat gun.

It's a pain to mix up a batch every time you want a couple of drops, though.  Going to order one of the Bondic UV pens and see how it works...

[mikeselectricstuff]

It's a pain to mix up a batch every time you want a couple of drops, though. 

The double-barrel syringe packs are handy for when you only want small amounts