Epoxy requirements - color,viscosity etc


#1

I am assemblying the v2.8 kit, and having troubles to find the recommended epoxy. Can I use a grey epoxy, or does it need to be transparent? Also, should I be worried about the viscosity of my epoxy being different than the recommended one?

I’m considering using jb weld ( http://www.jbweld.com/products/j-b-weld-twin-tube ) - 3960 psi, Set time 20-25 minutes, Cure time 15-24 hours. Provided I do the mixing correctly without the mix injector, would that work well? I noticed the set time is a little shorter than that of the recommended one (30 min). Would that be a problem?


#2

I have used an epoxy that sets a lot faster within like 5 minutes or so. This is really just a matter of timing. There is not a lot of time for corrections. The only time critical epoxy use is the connector, you need to make sure to that you entirely flood the cavities within the set time. Make sure you can apply enough pressure through the applicator. For this application transparent epoxy also helps a lot with finding the right amount of epoxy and pressure.

The viscosity does matter, maybe do a epoxy sample and see if you think it can fully fill the cavities. Good luck!


#3

Hello Felipe,

You can use whatever color epoxy you’d like. The advantage to clear epoxy is that you can see if there are any air gaps inside the cavities you are potting.

I would recommend using an injector nozzle. The pressure provided from the syringe helps push the air out of the cavities and replace airspace with epoxy. Also pouring epoxy from a cup into a tight space can be a messy affair.

Nima Torabi
OpenROV Support


#4

You can warm / heat most epoxy to lower the viscosity, but bear in mind it will reduce the set time if it cures by exothermic reaction. If it cures by UV or humidity it’s not a problem.


#5

Thank you all very much for sharing the knowledge! It helped me a lot!

Nima, yes, I intend to mix it myself and apply it into a syringe to use as an applicator. Hope that will do it, The only thing I can’t find here is the self-mixing one.

As for the color, I think I’ll have to settle for dark gray.

Thank you once again!


#6

Hello Felipe,

I see. Let me know how that works out! I know that getting non-syringe application epoxy is easier to acquire than syringe application epoxy in many places.

Best of luck!