Urethane Capaticence?

[petemoore]

I'm trying to see if there could be a problem using Urethane to encapsulate and insulate ckts.
 This stuff is really great !!!
 I just wrap like burrito, it softens easily, holds tall caps right in the sockets, completely insulates the 'module'.
 Then add some more to create tabs for mounting or build some up to match an existing wedge in the enclosure for super easy installation. This stuff properties make applying it in creative ways real easy.
 Its 20 mil thick urethane sheet. bonds to itself stronger than itself with heat, pretty clear..you can see right through it.
 I can get it to mold to whatever shape with just little dabs of heat here and there...not enough to cause troubles.
 Just trying to find if theres a fault in doing it this way ccause it seems to work great.

[Ansil]

sounds good to me

[brett]

Cool idea.  Where did you get your urethane?

[Peter Snowberg]

Hey Pete,

That sounds like interesting stuff. Where do you get it?

I can't foresee any problems using it. I've used expanding polyurethane foam for potting before and it worked great. I've also used polyurethane foam rubber, but I've never heard of it in a clear form.

Take care,
-Peter

[R.G.]

Great trick!

You shouldn't have problems. **Every** material other than air or vacuum has a dielectric constant greater than one, so substituting it in the space formerly occupied by air will increase parasitic capacitances. The questions are "how much?" and "will that hurt?"

If the circuit being wrapped does not use resistors over about 1M and does not have special bootstrapping features (very rare in effects) then you're likely fine. The change in capacitances are going to be minimal in almost all cases.

You might have hum problems if you don't shield, as urethane lets in RF and 60 cycle hum stuff.

So yes - where do you get that stuff?

[Paul Perry (Frostwave)]

Since urethane foam is mosly air, its capacitance is pretty low.
The only problem is that it is a GREAT insulator (thermal) and so, you certainly wouldn't wrap it around a tube!!
Most packing supply places sell it.

[petemoore]

and...before I forget again...lol
 Stevens Urethane
 Deerfield and Stevens...Dupont has a hand in the ingredients I believe
 Actually I was hoping [Im a Deerfield Rep [ I aughtta be]
 This IS the amazing stuff...
 I would recommend some of the teflon tape [supplier?...they're around]...with that and a soldering iron set low...we did extensive tests and it starts bonding at liek 275 degrees Faren...you just wrap like burrito, slap a small stretch of teftape on where you want the weld, and apply heat, then hold till warm...
 I tellin ya I looked at the finished product with the shieldedness, the wipable lookin clenliness, you can still see clear...and thought of the times I'd been looking all under the floor for that one part that kept falling under something from the socket...Takes a little finesse [not much] to get it perfect, by far the best I've seen...I really don't think you have to worry about burning parts to get this stuff to mold if you do it with breaks or not...it gets soft at like 225  [Ge's?]
 Actually 10 mil. might be the choice for some...[I gotta figure out xackli what Mil thik that was so...dohh] thinkin it was ten mil now...had to be...twenty mil is like raft material ... [Ill say ten mil or less]
 It also makes wonderful strat whammybar spring replacement [spring used to keep whammy where you can grab it]...get a glob going [with heat] about the diameter of the hole of the whammy threads, about 1/4'' tall, let it cool and put it in the hole and screw your whammy down on it...werx great for thousands of things...to get it out heat the end of a string and insert it, let it cool, and pull.
 I can't type to you the things I'vve used this stuff for...we made gloves from it [1-5mil]stamping two substrates with a heater element covered with teflon tape, we sealed and cut in one process...then we'd pull the gloves from the seamed sheets !!!
 Frank...maybe he still gives free samples?...lol

[petemoore]

Shielding material it is not...course you could maybe paint shielding on it???   !!

[AL]

Hey, wasn't the world famous "tube-u-lator" laquer some kind of urethane?  Sorry, I couldn't resist.

AL

[Bill_F]

Hey, wasn't the world famous "tube-u-lator" laquer some kind of urethane?  Sorry, I couldn't resist.

AL

So if I hear what your saying Al, this is just like wrapping the whole thing up in a tube.  A whole effect inside of a tube, that has to sound great! :lol:

[AL]

Hi Bill,

There was a discussion about this "wonder" of a high end audio-phile product a few months ago - tube-u-lator lacquer - and it was a good laugh.  Apparently someone marketed (or has a really good sense of humor ) a pricey lacquer that you were supposed to paint over your chips to make them sound like tubes.  It came with a custom applicator too - a q-tip.  Someone on this forum, in a burst of genius, suggested painting your ears with the stuff so everything sounded like tubes.

To all the people who actually wanted relevant information I apologize but I just couldn't resist.

AL

[AL]

Got it.  Again sorry guys this is OT.
If someone is going to actually reply to this we should probably take up this discussion in another post so we don't take up Pete's time here.

http://www.altmann.haan.de/tubeolator/default.htm

AL

[Bill_F]

Hi Bill,

There was a discussion about this "wonder" of a high end audio-phile product a few months ago - tube-u-lator lacquer - and it was a good laugh.  Apparently someone marketed (or has a really good sense of humor ) a pricey lacquer that you were supposed to paint over your chips to make them sound like tubes.  It came with a custom applicator too - a q-tip.  Someone on this forum, in a burst of genius, suggested painting your ears with the stuff so everything sounded like tubes.

To all the people who actually wanted relevant information I apologize but I just couldn't resist.

AL

Hi Al,

I remember the thread. I just thought it was funny that you brought it up and went along with it.

[petemoore]

Get your tube o lator all tube elated