Lead Dress and RTV? Opinions please…

[Raoul Duke]

Question for all the builders here:

Do you “lock-in” your lead dress once you get it where you want it by using RTV, tape, zip ties etc?

Looking through many build threads and also the originals they’re based on; I see a fair amount of this. I also own a couple of very well made and great sounding boutique builds that have this. I understand why and it makes sense, but “when” and “how much”?

For instance: if you set your lead dress up and find that it stays put pretty well, do you still use it?

Do you use it sparingly/as needed; or do you have a “regimen” that you’ve developed through time and experience that might be considered a small investment for big stability dividends or “cheap insurance”?

Does it depend on how much the amp is moved around, i.e. “gigging amp vs. home or studio use”?

Looking for some insight from those who’ve had more experience building.

Thanks in advance!

[maxkracht]

I ziptie or cable lace things when necessary, but tend to use components and wire that stays put pretty well. The lead dress to avoid unwanted interactions starts with layout, If I have to glue a wire to a specific spot, I probably screwed up somewhere... Most of the cable lacing, zip ties, or silicone I add is for mechanical support, to secure heavy things like caps, keep hot things from melty things, or just to keep things looking neat.

[xtian]

Be aware of wires running along the chassis--mechanical vibration during play can make them rattle.

[GAStan]

My experience with amps is very limited. I have used RTV silicone to secure caps in place and zip ties to bundle wires. I'm sure as I gain experience I'll likely use drop sized bits of RTV to secure wires in place.

However I do have a lot of experience securing wires and components in Radio Control models, both aircraft and offroad buggies. Both of these are very brutal on electronics with severe vibration and high G-forces. My regimen here was ties to bundle and anchor wires where anchor points were available. Strategically placed small blobs of RTV would secure wiring where no anchor points were available.

I learned to use the smallest amount of RTV required to facilitate removal of failed/broken components. This will be carried forward to amp building. I cannot see myself ever completely covering component(s) in goo.

Using RTV to maintain individual lead dress is something I hadn't actually considered until I read this post. I like the idea of small drops of strategically placed RTV for this purpose. It would also help alleviate the wire rattling mentioned in the previous post.

Edit: Because I don't know what the future holds for these amps, and because my hopes are they will be played often and for many years after I'm gone, I do like the idea of using RTV to secure leads and maintain dress. Once I'm satisfied with the dress I plan to do so.

[Raoul Duke]

Thanks guys!

maxkracht - point well taken and understood. Just completed my first build and spent a lot of time getting the solid core wire I used to go exactly where I wanted it - and it seems to stay put - but I’m a “belt and suspenders” kind of guy by nature so after seeing it in a few other builds; thought I’d ask if it’s common and how it’s implemented.

xtian - that’s definitely one of my concerns prompting the question.

Glenn - given your previous use of RTV in other electronics projects, I guess it isn’t so uncommon. I like the “strategically placed small drops” approach and will likely try it out.

I appreciate the input all
Hoping for more responses as well. Can never learn too much!

[xtian]

An alternative adhesive that I like is UV-cure resin. Tiny amounts can be used to glue wires together, to chassis, or other, and a cheap UV flashlight hardens the resin in about 30 seconds.

https://www.amazon.com/FlashFix-Plastic ... B099TFPPF4

[GAStan]

Since we're on the subject...during the 90's I worked for a military contractor and one product we used was G.E. RTV162, an electronics grade RTV with a high dielectric strength. It meets Mil. Specs and other standards. On one item we used it for it was subject to 3.6kv and we never had any issues with it. I can highly recommend it but I don't use it myself due to the fact it starts at about US $50 for a 2.8 Oz. tube.

I did find on Amazon ASI 388 RTV at US $10 for the same size tube which I have and use. It's electronics grade, non-corrosive to copper or brass, and low odor.

I believe the general consensus is that Dumble's goop is basically construction grade RTV.

[maxkracht]

Little dab of glue/silicone isn't going to hurt anything, but be careful not to overdo things and make later repairs harder than necessary. I was definitely guilty of the, wrap wire all the way around a turret, maybe even twice so it won't go anywhere, newbie mistake. Learned that one the hard way...

Maybe a more authoritative opinion would help. https://archive.org/details/nasa-workma ... 1/mode/2up

[FUCHSAUDIO]

Be aware of wires running along the chassis--mechanical vibration during play can make them rattle.

Ampeg used contact cement liberally on the old Jersey builds. They used solid core wire dressed down against the chassis, and then a coating of rubber cement to stop movement.

[Stevem]

Yes they sure did and that’s in part why there still nicely playable today.

[Raoul Duke]

Very interesting, thanks guys!
The Ampeg/NJ connection must be where Ken F. saw it first? IIRC I’ve seen gunshots of TWs with a little dab on preamp wires.