[PSUBS-MAILIST] Emer Buoy brake and clear resin

Sun Feb 9 12:51:15 EST 2025

Those off road lights are pretty cheap these days, so I figured the epoxy
was worth a try even if I burned one out. Jon, you were asking about the
yellowing, I ended up using a casting acrylic that was for art projects, it
ended up working pretty well and didn't have too many bubbles even without
using a vacuum to cure it. So far it hasn't changed color at all, but the
only action it's seen is sitting on my shelf patiently waiting for the sub
to get done...

On Sat, Feb 8, 2025 at 5:14 PM Jon Wallace via Personal_Submersibles <
personal_submersibles at psubs.org> wrote:

> Hank,
>
> I think you were correct the first time, 36-48 inch light bars are
> advertised with power ratings of 200-240 watts. Most double-A (AA) LED
> flashlights have more intensity than 200 lumens and even the good old
> sealed beam automotive headlights with tungsten filaments averaged 1100
> lumens. I'm sure your light bar consumes a couple hundred watts, or close
> to it.
>
> Jon
>
> On Saturday, February 8, 2025 at 06:38:41 PM EST, hank pronk via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> Justin,
> I think you are right on the money.  I miss spoke, I meant 200 lummen.  I
> did not have the heat sink on the board.  I simply submerged the board in
> casting resin and it failed right away.  Had I mounted it to the heat sink,
> I may have worked.  This will make for some real chaep reliable lighting.
> Hank
>
> On Saturday, February 8, 2025 at 02:16:17 PM MST, Justin Helland via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> Just to add my single anec-data point, I filled an off-roading light with
> epoxy and let it sit powered overnight and it seemed to work fine, although
> it was less powerful than Hank's 200W, I think it was 60W. But the off road
> lights have pretty solid housings with radiating fins, so maybe as long as
> the light has enough mass in the housing connected to a heat sink you might
> be okay. But I like Sean's suggestion of thermal epoxy, I bet if you could
> get the thermal epoxy to contact the LED board as well as the housing you'd
> be golden.
>
> On Sat, Feb 8, 2025 at 10:50 AM hank pronk via Personal_Submersibles <
> personal_submersibles at psubs.org> wrote:
>
> Sean,
> I used casting resin, and not very thick, maybe 1\2 inch.  It would have
> been maybe 200 W  and it was submerged.  A test with a heat gun would be a
> good idea to start with.   You could make the epoxy extemly thin and try it
> with the thermal epoxy.   It only needs to seal out water.  Oil cmpensating
> has proven the components can handle pressure (1200 psi).   If Jon can make
> this work it would be fantastic.
> Hank
>
> On Friday, February 7, 2025 at 09:20:56 PM MST, Sean T. Stevenson via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> What epoxy did you use, and how powerful was the LED?
>
> I wonder about the possibility of a two part pour, where a relatively thin
> layer would be poured only between the emitter and the lens using a clear
> epoxy like this:
>
>
> https://mgchemicals.com/products/potting-compounds/epoxy-potting/clear-epoxy-resin/
>
> ...and then a separate pour could be done between the back side of the
> emitter / electronics and the housing / heat sink, using a thermally
> conductive epoxy like this:
>
>
> https://mgchemicals.com/products/potting-compounds/epoxy-potting/thermally-conductive-epoxy/
>
> Would depend I guess on how much heat the LED package puts out, the
> temperature of the surrounding water, and the efficacy of the housing heat
> sink.  Was your test immersed?
>
> Sean
>
> On Friday, February 7th, 2025 at 13:05, hank pronk via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
> Jon,
> I tested an LED light in epoxy and it bunt up pretty quickly.
> Hank
>
> On Tuesday, February 4, 2025 at 12:39:54 PM MST, Jon Wallace via
> Personal_Submersibles <personal_submersibles at psubs.org> wrote:
>
>
> Hello folks, looking for some suggestions.
>
> 1) Are you braking your spool of rope for the emergency flotation buoy so
> that it doesn't unravel during normal operations or do you find it
> unnecessary?  If so, can you describe how you are braking your spool?
>
> 2) I'm testing a set of off-the-shelf 12v led lights (4 inch round) and
> was going to oil compensate them but now I'm thinking about just filling
> the entire void with a clear non-yellowing epoxy.  I don't see the units as
> having any useful or serviceable parts upon failure regardless of
> compensation method so sealing them permanently with epoxy seems like a
> viable and perhaps less messy method in the long run.  The units would
> require approximately 1.25 inches (31.75mm) depth of epoxy to fill them and
> my only concern is what effect the dry epoxy will have on the light
> emanating from the units.  Any thoughts?
>
>
> Jon
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20250209/83dd6c9f/attachment.html>