Low viscosity low curing temp potting material

[fieldwrangler]

Folks -

I have an application that requires some kindof juice as described above; any ideas?

Bob Palmieri

[frankfalbo]

What (if anything) don't you like about lacquer(s)? Can we know a little more about the finished project requirements? Are you meaning the term "potting" as simply microphonic squelch in an open design, or do you need this to become a structural brick of sorts?

[fieldwrangler]

What (if anything) don't you like about lacquer(s)? Can we know a little more about the finished project requirements? Are you meaning the term "potting" as simply microphonic squelch in an open design, or do you need this to become a structural brick of sorts?

Frank -

Thanks for this! It's a very unusual wafer (can't post a snap as this design is owned by my company.)
Top & bottom flanges are very thin and bonded to the core with CA glue. This one would seem to need 2 stages - one with something thin that doesn't get too hot for the windings and a second stage to stiffen the thing into the "structural brick" you described.

Bob Palmieri

[Chuck H]

Is there a way to saturate the whole thing in CA and then end cap it and hold while the CA sets? One less product eliminating half a step, sort of. Though it would be cumbersome to do by hand there may be an automated way to do it.

[jack briggs]

lacquer, but one step further: sanding sealer. essentially lacquer with more solids and stearate (wax) added.


cheers,

[fieldwrangler]

Is there a way to saturate the whole thing in CA and then end cap it and hold while the CA sets? One less product eliminating half a step, sort of. Though it would be cumbersome to do by hand there may be an automated way to do it.

I like this idea, for Shure. However, I seem to have experienced some instances in which the really thin CA that penetrates the coil also gets hot enough to melt the insulation.

[fieldwrangler]

lacquer, but one step further: sanding sealer. essentially lacquer with more solids and stearate (wax) added.


cheers,

Cool idea. Do we think that stuff is thin enough to penetrate the windings?

[potatofarmer]

lacquer, but one step further: sanding sealer. essentially lacquer with more solids and stearate (wax) added.


cheers,

Is there a brand you've used for this? I know the Zinsser sanding sealer is just shellac, albeit wax-free and dilute (2 pound cut, IIRC?) - are there lacquer-based ones as well?

[frankfalbo]

Not sure I like air-dry for something that will be later trapped in a brick. If it's still gassing off, when it's trapped there are a couple plausible unintended consequences. There are probably 2-part polys that are guaranteed to cure with a high solids content and less shrink. For the "brick" you just have to check the curing temps of whatever epoxy. The manufacturers will know and disclose. Do you know your actual fail temp? Also is it something you can do with bondable wire?

[Chuck H]

I was thinking the same. Anything but a catalyzed product requires evaporation. I mean, they sell the stuff in a plastic can and what is a block but a plastic can of a different shape! Also, if the strength of this a/b poly is sufficient you could still do away with the added CA step for the flanges. It's just a matter of finding a product that has suitable bonding, relatively low shrink and a cure temp that won't damage the jacket. Which is sort of the question in the opening post, but at least we've added the potential for faster MFG once a product is found.

I think it would be a good next step to research the safe temp for the wire jacket and the minimum bonding strength required for the flanges under whatever stresses this product will be used for. Then email a few companies that make adhesives. I researched one such company and was amazed at the options and how the specs are laid out.

[fieldwrangler]

Folks -

This is definitely serving as an education in parameters, considerations & alternatives.

However, I now see a bigger fish that needs to be fried; see next post...

Bob Palmieri

[David King]

CPES from Bob Smith Industries. Or you can look through all the the potting choices at Epoxies.com
You don't want anything that's going to shrink so an epoxy or polyester is the way to go.