wax and EVA ratio information

[Jon I]

This message is in response to Mr. Horton, who wanted to know a while
back how much of the EVA glue sticks were needed to make paraffin
properties more suitable for electronics potting. I have the answer as
I have now done it about ten times: 5%. Simply determine how much
weight or volume of paraffin you will use, then calculate 5% of that and
add your sticks. I use the low temperature sticks. You can pick these
up at Michael's art stores or even some Walmarts have them.

Three years ago, I was in a similar situation to yours and not sure
whether I should use wax or a wax mix to pot something that was going to
be in environmental extremes of temperature even greater than yours. I
did some trials first and determined the 5% suitability, then did the
final paraffin-EVA mix. The potted circuit board and transformer have
been in temperatures from 0-98 F since that time and no cracks or
distortions of any kind. There is evidence of slight, very slight,
shrinkage, but far less so than using paraffin by itself. Therefore, I
highly recommend the paraffin-EVA mix at 5%.

Hope that helps you out! You can save quite a few dollars potting this
way versus actual potting compounds and such and now you have the trials
and proof go go along with it. Good luck!

 

[Jim Horton]

On 11/2/19 3:59 PM, Jon I wrote:

This message is in response to Mr. Horton, who wanted to know a while
back how much of the EVA glue sticks were needed to make paraffin
properties more suitable for electronics potting.  I have the answer as
I have now done it about ten times: 5%.  Simply determine how much
weight or volume of paraffin you will use, then calculate 5% of that and
add your sticks.  I use the low temperature sticks.  You can pick these
up at Michael's art stores or even some Walmarts have them.

Three years ago, I was in a similar situation to yours and not sure
whether I should use wax or a wax mix to pot something that was going to
be in environmental extremes of temperature even greater than yours.  I
did some trials first and determined the 5% suitability, then did the
final paraffin-EVA mix.  The potted circuit board and transformer have
been in temperatures from 0-98 F since that time and no cracks or
distortions of any kind.  There is evidence of slight, very slight,
shrinkage, but far less so than using paraffin by itself.  Therefore, I
highly recommend the paraffin-EVA mix at 5%.

Hope that helps you out!  You can save quite a few dollars potting this
way versus actual potting compounds and such and now you have the trials
and proof go go along with it.  Good luck!

Thanks for this information. Although I am past this now and have
simply been testing the paraffin blocks by themselves, should I decide
to try the EVA additive again, I will mix the way you describe.

 

[Chris Jones]

On 03/11/2019 07:08, Jim Horton wrote:

On 11/2/19 3:59 PM, Jon I wrote:
This message is in response to Mr. Horton, who wanted to know a while
back how much of the EVA glue sticks were needed to make paraffin
properties more suitable for electronics potting.  I have the answer
as I have now done it about ten times: 5%.  Simply determine how much
weight or volume of paraffin you will use, then calculate 5% of that
and add your sticks.  I use the low temperature sticks.  You can pick
these up at Michael's art stores or even some Walmarts have them.

Three years ago, I was in a similar situation to yours and not sure
whether I should use wax or a wax mix to pot something that was going
to be in environmental extremes of temperature even greater than
yours.  I did some trials first and determined the 5% suitability,
then did the final paraffin-EVA mix.  The potted circuit board and
transformer have been in temperatures from 0-98 F since that time and
no cracks or distortions of any kind.  There is evidence of slight,
very slight, shrinkage, but far less so than using paraffin by
itself.  Therefore, I highly recommend the paraffin-EVA mix at 5%.

Hope that helps you out!  You can save quite a few dollars potting
this way versus actual potting compounds and such and now you have the
trials and proof go go along with it.  Good luck!

Thanks for this information.  Although I am past this now and have
simply been testing the paraffin blocks by themselves, should I decide
to try the EVA additive again, I will mix the way you describe.

I have heard that incompletely crosslinked EVA can decompose to acetic
acid (vinegar), and that this can be a problem in solar panels that have
not been manufactured with due care and proper materials.

 

[Jim Horton]

On 11/3/19 8:45 PM, Chris Jones wrote:

I have heard that incompletely crosslinked EVA can decompose to acetic
acid (vinegar), and that this can be a problem in solar panels that have
not been manufactured with due care and proper materials.

The author replying to me did not indicate this with his potting of
electronics, but if it does happen it could be a major problem. I've
already gone through this with bathroom type silicone corroding copper
wiring, but thankfully doesn't bother stainless which is what I usually
use as feedthrough (or recently I just swapped silicone for JB Weld two
part epoxy).

 

[Rick C]

On Sunday, November 3, 2019 at 8:45:56 PM UTC-5, Chris Jones wrote:

On 03/11/2019 07:08, Jim Horton wrote:
On 11/2/19 3:59 PM, Jon I wrote:
This message is in response to Mr. Horton, who wanted to know a while
back how much of the EVA glue sticks were needed to make paraffin
properties more suitable for electronics potting.  I have the answer
as I have now done it about ten times: 5%.  Simply determine how much
weight or volume of paraffin you will use, then calculate 5% of that
and add your sticks.  I use the low temperature sticks.  You can pick
these up at Michael's art stores or even some Walmarts have them.

Three years ago, I was in a similar situation to yours and not sure
whether I should use wax or a wax mix to pot something that was going
to be in environmental extremes of temperature even greater than
yours.  I did some trials first and determined the 5% suitability,
then did the final paraffin-EVA mix.  The potted circuit board and
transformer have been in temperatures from 0-98 F since that time and
no cracks or distortions of any kind.  There is evidence of slight,
very slight, shrinkage, but far less so than using paraffin by
itself.  Therefore, I highly recommend the paraffin-EVA mix at 5%..

Hope that helps you out!  You can save quite a few dollars potting
this way versus actual potting compounds and such and now you have the
trials and proof go go along with it.  Good luck!

Thanks for this information.  Although I am past this now and have
simply been testing the paraffin blocks by themselves, should I decide
to try the EVA additive again, I will mix the way you describe.

I have heard that incompletely crosslinked EVA can decompose to acetic
acid (vinegar), and that this can be a problem in solar panels that have
not been manufactured with due care and proper materials.

Is the EVA crosslinked by UV light by any chance? I didn't find anything about this when I looked.

I did find that a water proofing product, Nicwax, is made by mixing EVA and "mineral wax". They claim to alter the mineral wax by changing it molecular structure... whatever that means. I guess they changed it chemically somewhat. They wanted to make it less brittle. So maybe mixing the two is not a terrible idea.

--

Rick C.

- Get 1,000 miles of free Supercharging
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--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[Chris Jones]

On 04/11/2019 17:03, Rick C wrote:

On Sunday, November 3, 2019 at 8:45:56 PM UTC-5, Chris Jones wrote:
On 03/11/2019 07:08, Jim Horton wrote:
On 11/2/19 3:59 PM, Jon I wrote:
This message is in response to Mr. Horton, who wanted to know a while
back how much of the EVA glue sticks were needed to make paraffin
properties more suitable for electronics potting.  I have the answer
as I have now done it about ten times: 5%.  Simply determine how much
weight or volume of paraffin you will use, then calculate 5% of that
and add your sticks.  I use the low temperature sticks.  You can pick
these up at Michael's art stores or even some Walmarts have them.

Three years ago, I was in a similar situation to yours and not sure
whether I should use wax or a wax mix to pot something that was going
to be in environmental extremes of temperature even greater than
yours.  I did some trials first and determined the 5% suitability,
then did the final paraffin-EVA mix.  The potted circuit board and
transformer have been in temperatures from 0-98 F since that time and
no cracks or distortions of any kind.  There is evidence of slight,
very slight, shrinkage, but far less so than using paraffin by
itself.  Therefore, I highly recommend the paraffin-EVA mix at 5%.

Hope that helps you out!  You can save quite a few dollars potting
this way versus actual potting compounds and such and now you have the
trials and proof go go along with it.  Good luck!

Thanks for this information.  Although I am past this now and have
simply been testing the paraffin blocks by themselves, should I decide
to try the EVA additive again, I will mix the way you describe.

I have heard that incompletely crosslinked EVA can decompose to acetic
acid (vinegar), and that this can be a problem in solar panels that have
not been manufactured with due care and proper materials.

Is the EVA crosslinked by UV light by any chance?

Normally it comes in flexible sheets and is melted and then cured
(crosslinked) by heating it. If properly made it is stable under UV, or
at least those wavelengths of the UV that aren't stopped by the glass.