Silicone to Secure Transistors in Sockets?

[zombiwoof]

I have the trannies socketed in my Fuzz Face, the leads are bent over to keep the trannies low to the board.  Even though the connections are secure, the trannies wobble a bit in the sockets and I was thinking of applying a bit of silicone to them to keep them from moving around.  Is there any reason to not do this?.  Is there something better to use?.

Thanks.

[Gus]

The best thing to do is learn to solder quickly, this comes with practice and a good temp controlled iron.  If you know how to solder quickly and well you can remove and replace parts almost as fast as using a socket, without harming the part or the PCB.  I avoid using sockets when ever possible.

The other stuff in the silicone might corrode the wires in the circuit

[zombiwoof]

The best thing to do is learn to solder quickly, this comes with practice and a good temp controlled iron.  If you know how to solder quickly and well you can remove and replace parts almost as fast as using a socket, without harming the part or the PCB.  I avoid using sockets when ever possible.

The other stuff in the silicone might corrode the wires in the circuit

I know how to solder, I just have sockets in this pedal to allow trying different transistors.  I just want to know if there is some reason to not use the silicone where the transistor fits in the socket.  I don't plan on getting it on any wires.

Al

[Mark Hammer]

Take an alligator clip and pinch the opt of the leads near the tranny to soak up excess heat.  Tin the ends of the leads just a bit to increase their diameter.  Shove 'em back in the socket.

[roseblood11]

... or use a bit of hot glue, if you plan to swap the transistors again.

[R.G.]

Most of the common "RTV" compounds have acetic acid in them - that's the vinegar smell you get when  you use them.

A good recipe to corrode metals - like contacts - is to pour acid on them.

[Gus]

A link for you.  You can solder things in from the top.

http://www.keyelco.com/pdfs/p96.pdf

Look up what else is in the silicone.  Check if it will corrode wires.  I did post about corroding wires in my first post

I would expect people to look up what is inside the silicone.  The web makes it so easy.

Google the MSDS of the silicone you might use

[R.G.]

I did post about corroding wires in my first post
[/quote]
So you did. Sorry I missed that one. You're right!

[zombiwoof]

Thanks, that's what I was wondering, if the silicone had anything in it that would be bad for the components.  Hot glue is a good option.  I was trying to think of what to use, and I wanted something that would hold but be temporary in case I wanted to try other trannies in the pedal.  At some point I may solder them in when I'm sure that I'm satisfied, but for now I just want them secured.

Al

[earthtonesaudio]

How about drill a couple extra holes in the board, bend the transistor so it's flush against the board, and wire-tie it in place?

Or even better, find some p-clips just slightly smaller than the transistor's diameter, and bolt that sucker on.

[candidate]

Secure the transistor in a spare socket.  Plug that socket into the socket on the board.  Works when swapping ICs too.

[dudleydoright]

Go to Fry's and get some of the silicone designed for electronics use. Cheap and simple if you must do it this way.

[FlyingZ]

Hot glue will conduct after time.

[JKowalski]

Hot glue will conduct after time.

Not all "hot glue". As proof, I used hot glue (your standard hot glue stick + gun) to secure a bank of 45 400V capacitors together for a tesla coil where the peak voltage possible across the glue is as high as 17,000 volts. The way it's made though, I'd say the highest voltage across a stretch of the hot glue is probably half of that at least.

But it's certainly possible that some types are.

[FlyingZ]

A TV repairman told me from his experience a little string will get you in time. No mention of glue brand.

[zombiwoof]

I was not planning on putting either glue or silicone across components, I was just going to use it to secure each transistor to keep them from moving around.  In other words, it would not cover more than one component at a time, or have any route to conduct between them.  I would also try to not get it across the leads.  I was wondering however if either hot glue or silicone would conduct.  I also was not aware that there is a special electronics silicone, so thanks for that tip.

Thanks,
Al

[greaser_au]

Hi Al,

just some general comments on silicone rubber from my time in electronics manufacturing:  
One-part RTV (room temperature vulcanising) silicone rubber comes in two main types: acid cure & neutral cure, both rely on atmospheric humidity to trigger the curing process. Acid cure releases acetic acid (vinegar) fumes as it cures. naturally, this is slightly corrosive. I used to mess around with antenna baluns/coax transformers & unplated coax braid used to go green when feedpoints or junction boxes were packed with acid cure.  Acid cure is typically used as window/glass sealant (look for 24 hour cure time or a mention of vinegar smell on the label- and avoid it for electronics).
Neutral cure usually pops up as roof/gutter or concrete sealant with a 72 hour cure time. In practice it's ok to use it after 24 hours but make sure you leave it for 72 hours before putting it in a sealed box. Suggest you get clear RTV if you aren't buying specific electronics-grade stuff to avoid unusual fillers - look for stuff that mentions electrical uses & most importantly says 'non-corrosive' on the label. The 'real thing' for electr[ical|onic] uses is Dow Corning RTV738.
As adhesives go, it has fairly low shear strength, so I  always apply a bead of it,  either under a bit of pressure or wipe a thin film on both surfaces with a toothpick immediately before I apply the bead if I want maximum bond strength.

I read in an old Isaac Asimov science book (X Stands for Unknown) that this whole family of materials is the silicon analogue of common carbon compounds like oil and plastics, & this series of essays goes on to discuss the theoretical chemical possibility of silicon organics - a very interesting read, even after all this time!

david.

[petemoore]

  beam across the Q-tops, stud into perfhole [toothpick framing].
  G-glue for stud-hole, any adhesive for the Q-top and frame corners [beam laid across the transistor, simple/easy, pulls right off, pins them in.
  Let the beam dry to transistors tops, angle the stud into the hole so it's top is pressed */ to the cross-beam.
  * Being end view of beam which touches the / angled stud piece...spring in the toothpick pins it to the beam for drying.
  Teeny bead of Gorilla Glue is easy to keep neat on toothpick tip, wedged into perfhole.