mineral oil removal/ DIY wax embedding?

J

Jim Horton

Guest
Hi. I have an old project that had high voltage components under
mineral oil, the container of which I discovered today was leaking.
Since paraffin was originally recommended, I am in the process of
draining out the oil with the intention of wax embedding later.
However, I am left with mineral oil residue, not only on the high
voltage components, but on the screw driver, floor, etc, a mess really.
What's something I can use that will remove the oil?

Also, as I have never wax potted anything, I would appreciate any
advice. I was going to try doing this in the oven and allow the molten
wax plenty of time to air out, etc, but I'm not sure I can do it in my
oven as it only gets down to 175 F. The components would be in the oven
in a plastic container, most likely similar to an electronic pvc
junction box.

This was a strictly DIY project to begin with so no commercial or safety
elements. Thanks in advance for any help.
 
Jim Horton <jhorton@nospam.net> wrote:
On 10/15/19 11:55 AM, Winfield Hill wrote:
Jim Horton wrote...

What's something I can use that will remove the oil?

Detergent and water does a good job on oils.
If your oil is recalcitrant, dissolve it in
a more friendly oil, even cheap cooking oil.

What about the oil on the transformer? It is an HEI ignition type that
had been in the mineral oil. I probably should have mentioned it
before. It is the oil I need to remove from this mainly before I pot in
the wax.

3M's Citrus Base Cleaner removes oil. You can then use IPA as a rinse
afterward.

Thank you, 73,

--
Don Kuenz, KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.
 
On 10/15/19 11:55 AM, Winfield Hill wrote:
Jim Horton wrote...

What's something I can use that will remove the oil?

Detergent and water does a good job on oils.
If your oil is recalcitrant, dissolve it in
a more friendly oil, even cheap cooking oil.

What about the oil on the transformer? It is an HEI ignition type that
had been in the mineral oil. I probably should have mentioned it
before. It is the oil I need to remove from this mainly before I pot in
the wax.
 
Jim Horton wrote...
What's something I can use that will remove the oil?

Detergent and water does a good job on oils.
If your oil is recalcitrant, dissolve it in
a more friendly oil, even cheap cooking oil.


--
Thanks,
- Win
 
Winfield Hill <winfieldhill@yahoo.com> wrote in
news:qo4q5l011tv@drn.newsguy.com:

Jim Horton wrote...

What's something I can use that will remove the oil?

Detergent and water does a good job on oils.
If your oil is recalcitrant, dissolve it in
a more friendly oil, even cheap cooking oil.

Sop up absolutely as much as possible. Heat the device, enclosure
and all, and allow it to drain to a corner of the enclosure to pour
out, then heat again and tip and rest on another corner angle and let
drain again. Then, you can flush the container and device. The
thing is to choose the right solvent. Obviously not aqua based
unless you plan on baking it for a while and even vacuum bake
ideally.

Seems like a vacuum would be needed to fully impregnate the wax as
well.
 
On 15/10/2019 16:32, Jim Horton wrote:
Hi.  I have an old project that had high voltage components under
mineral oil, the container of which I discovered today was leaking.
Since paraffin was originally recommended, I am in the process of
draining out the oil with the intention of wax embedding later. However,
I am left with mineral oil residue, not only on the high voltage
components, but on the screw driver, floor, etc, a mess really. What's
something I can use that will remove the oil?

Kerosene is probably the most likely solvent that isn't too aggressive
and will remove oil from the thing without dissolving much else and then
evaporate leaving it mostly oil free.

Also, as I have never wax potted anything, I would appreciate any
advice.  I was going to try doing this in the oven and allow the molten
wax plenty of time  to air out, etc, but I'm not sure I can do it in my
oven as it only gets down to 175 F.  The components would be in the oven
in a plastic container, most likely similar to an electronic pvc
junction box.

Candle makers add stearin to classic soft paraffin wax to increase its
melting point to 80C which makes it more rigid and gives a slower
burning flame.

This was a strictly DIY project to begin with so no commercial or safety
elements.  Thanks in advance for any help.

Even so be careful you don't get it ignited by accident.
More of a risk when cleaning things with a flammable solvent.

--
Regards,
Martin Brown
 
On 2019/10/15 9:45 a.m., Martin Brown wrote:
On 15/10/2019 16:32, Jim Horton wrote:
Hi.  I have an old project that had high voltage components under
mineral oil, the container of which I discovered today was leaking.
Since paraffin was originally recommended, I am in the process of
draining out the oil with the intention of wax embedding later.
However, I am left with mineral oil residue, not only on the high
voltage components, but on the screw driver, floor, etc, a mess
really. What's something I can use that will remove the oil?

Kerosene is probably the most likely solvent that isn't too aggressive
and will remove oil from the thing without dissolving much else and then
evaporate leaving it mostly oil free.

Mineral spirits is suggested over kerosene for cleaning...

https://www.wisegeek.com/what-are-mineral-spirits.htm

John :-#)#
 
On Tue, 15 Oct 2019 16:34:52 +0000, Don Kuenz, KB7RPU wrote:

Jim Horton <jhorton@nospam.net> wrote:
On 10/15/19 11:55 AM, Winfield Hill wrote:
Jim Horton wrote...

What's something I can use that will remove the oil?

Detergent and water does a good job on oils.
If your oil is recalcitrant, dissolve it in a more friendly oil,
even cheap cooking oil.

What about the oil on the transformer? It is an HEI ignition type that
had been in the mineral oil. I probably should have mentioned it
before. It is the oil I need to remove from this mainly before I pot
in the wax.

3M's Citrus Base Cleaner removes oil. You can then use IPA as a rinse
afterward.

On the floor, yes. On the transformer, NO! It could damage the
insulation. So, just use something absorbent, like paper towels, and
replace periodically until it is dry enough for your purposes.

Jon
 
Jon Elson <elson@pico-systems.com> wrote:
On Tue, 15 Oct 2019 16:34:52 +0000, Don Kuenz, KB7RPU wrote:

Jim Horton <jhorton@nospam.net> wrote:
On 10/15/19 11:55 AM, Winfield Hill wrote:
Jim Horton wrote...

What's something I can use that will remove the oil?

Detergent and water does a good job on oils.
If your oil is recalcitrant, dissolve it in a more friendly oil,
even cheap cooking oil.

What about the oil on the transformer? It is an HEI ignition type that
had been in the mineral oil. I probably should have mentioned it
before. It is the oil I need to remove from this mainly before I pot
in the wax.

3M's Citrus Base Cleaner removes oil. You can then use IPA as a rinse
afterward.

On the floor, yes. On the transformer, NO! It could damage the
insulation. So, just use something absorbent, like paper towels, and
replace periodically until it is dry enough for your purposes.

"floor" ??? Do you care explain what you mean?

3M's Citrus Base Cleaner is formulated to remove thermal grease from
processors, among other things. It's more-or-less the first treatment of
the Arctic Silver thermal material remover.

Thank you, 73,

--
Don Kuenz, KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.
 
Thanks for all the advice, but I ended up going with QC Electronic Parts
Cleaner. It can be found both at the auto store as well as Walmart,
with Walmart's being half the cost. It took 3 cans to get the inside of
the enclosure and transformer mineral oil free, at least from what I
could tell. I didn't see or smell any residue so pressed on.

The next part was finding wax, which I had a hard time doing. Hard to
believe a place like Walmart doesn't carry it except by special order.
I had to travel a bit, but found some at Hobby Lobby. Not cheap, but I
did need 6.5 lbs.

Since I am a newbie at this, I first placed the now clean transformer
and container in the oven with a wax brick, and set the temp at the
lowest setting of 170 F. However, I could see this was going to take
forever to melt, so I placed a coffee can within a larger pot and put
some water in the pot to reach boiling. It took several melts of the
wax, but each time it melted well and I opened the oven and poured it
into the transformer box. I have moisture concerns, but it *seems* like
any water in the molten wax was at the bottom. I hope that's correct.

I spilled some while pulling out the transformer container to fill it.
It was caught by a foil pan I got at the dollar store, but I'm probably
going to have a breakaway around the bottom job once solid.

I am letting it cool down slowly. I turned the oven off, but I am
keeping the door closed. I don't worry too much since this is an
already sealed transformer, but then again I didn't want to cool things
too quickly either.

Now to just hope I did it right and the wax does its job as replacement
insulator for the mineral oil.
 
Jim Horton wrote:
Hi.  I have an old project that had high voltage components under
mineral oil, the container of which I discovered today was leaking.
Since paraffin was originally recommended, I am in the process of
draining out the oil with the intention of wax embedding later. However,
I am left with mineral oil residue, not only on the high voltage
components, but on the screw driver, floor, etc, a mess really. What's
something I can use that will remove the oil?

Also, as I have never wax potted anything, I would appreciate any
advice.  I was going to try doing this in the oven and allow the molten
wax plenty of time  to air out, etc, but I'm not sure I can do it in my
oven as it only gets down to 175 F.  The components would be in the oven
in a plastic container, most likely similar to an electronic pvc
junction box.

This was a strictly DIY project to begin with so no commercial or safety
elements.  Thanks in advance for any help.
It helps greatly to do that in a vacuum...
 
On 2019-10-15, John Robertson <spam@flippers.com> wrote:
On 2019/10/15 9:45 a.m., Martin Brown wrote:
On 15/10/2019 16:32, Jim Horton wrote:
Hi.  I have an old project that had high voltage components under
mineral oil, the container of which I discovered today was leaking.
Since paraffin was originally recommended, I am in the process of
draining out the oil with the intention of wax embedding later.
However, I am left with mineral oil residue, not only on the high
voltage components, but on the screw driver, floor, etc, a mess
really. What's something I can use that will remove the oil?

Kerosene is probably the most likely solvent that isn't too aggressive
and will remove oil from the thing without dissolving much else and then
evaporate leaving it mostly oil free.

Mineral spirits is suggested over kerosene for cleaning...

https://www.wisegeek.com/what-are-mineral-spirits.htm

That stuff will attack polystyrene, and possibly also other plastics used
in electronics.



--
When I tried casting out nines I made a hash of it.
 
After letting cool all night in the oven, I pulled out the potted
transformer this morning. I was surprised that some of the wax settled
in the center of the junction box, about 1.5" depression in an area
roughly 1.5" or so wide. It wasn't enough to expose anything, but a
surprise. I was tempted to melt and add more wax to this area today,
but since nothing was exposed, just covered it over with the junction
box cover and was done. Although I could still feel a bit of warmth
coming from the box, I did a quick test after hooking up the driving
circuitry. Sparking is what it should be, just as before with the
mineral oil.

I know others have mentioned doing something like this under vacuum, but
for a budget limited hobbyist like myself, it's pretty much out of the
question. I'm also not sure how I would go about it with hot wax. I do
have a small chamber and single stage pump handy, but those are for
insect drying and nothing the size of this transformer box.
 
Jim Horton <jhorton@nospam.net> wrote in
news:qo6tg6$62a$1@dont-email.me:

I know others have mentioned doing something like this under
vacuum, but for a budget limited hobbyist like myself, it's pretty
much out of the question. I'm also not sure how I would go about
it with hot wax. I do have a small chamber and single stage pump
handy, but those are for insect drying and nothing the size of
this transformer box.

You do not need a full vacuum, so you can fashion your own chamber
and used vac pumps are cheap.

You just need a lower pressure to allow the air to expand and
bubble out, and the was to migrate in.

One problem is that if you are having an arcing condition, they
typically cause carbon tracks to form, and even subsequent potting
without treating those established pathways may result in a failure
mode even with fully vacuum potted jobs.

We had power supplies where if the builder breathed 'coffee
breath' on the multiplier section before potting, it would cause
subsequent detachment, and detached potting is like no potting in the
HV realm, and failure is certain.

I just saw some on ebay doing a search on "vacuum pumps" and they
have one new for like $49. So the used ones are probably dirt cheap.
 
On 10/16/19 8:33 AM, DecadentLinuxUserNumeroUno@decadence.org wrote:
Jim Horton <jhorton@nospam.net> wrote in
news:qo6tg6$62a$1@dont-email.me:

I know others have mentioned doing something like this under
vacuum, but for a budget limited hobbyist like myself, it's pretty
much out of the question. I'm also not sure how I would go about
it with hot wax. I do have a small chamber and single stage pump
handy, but those are for insect drying and nothing the size of
this transformer box.



You do not need a full vacuum, so you can fashion your own chamber
and used vac pumps are cheap.

You just need a lower pressure to allow the air to expand and
bubble out, and the was to migrate in.

One problem is that if you are having an arcing condition, they
typically cause carbon tracks to form, and even subsequent potting
without treating those established pathways may result in a failure
mode even with fully vacuum potted jobs.

We had power supplies where if the builder breathed 'coffee
breath' on the multiplier section before potting, it would cause
subsequent detachment, and detached potting is like no potting in the
HV realm, and failure is certain.

I just saw some on ebay doing a search on "vacuum pumps" and they
have one new for like $49. So the used ones are probably dirt cheap.

Thanks. I do have one of the Ebay $49 pumps (actually Amazon). I used
it to pump out a Mason jar with caterpillars inside (after the
caterpillars were frozen). By evacuating the air, the caterpillars
freeze dried within 2 weeks.

However, after a couple of years in storage, I brought out the pump
recently to find a small puddle of oil underneath. Luckily, with
anything that has oil inside, I always store in a container large enough
so that if it leaks, nothing gets on the floor or shelves.

This was a pump I hardly ever used. That will be my next project, to
see if I can find and repair the leaks. For now, all the remaining oil
was drained and I have it in a new containment bin until I can get
around to it.

This project uses two HEI ignition coils with outputs opposite phased.
It is driven by a quadrac circuit to produce up to 5" sparks between
electrodes. So the insulation really is for around the transformers as
the HEI coils themselves are already potted of course and now in the wax
too. For years, the PVC junction box housing with mineral oil worked
fine until I saw seepage into yet another storage bin that surrounded
the assembly while in storage. I'm still not sure how the oil seeped
out. I had connections into and out of the box, but carefully sealed
the single wires with silicone (I made sure not to use stranded wire
anywhere), so it didn't appear to be my seals that leaked. Anyway, I
now have it all back together and 5" sparking. Of course, I don't have
to have the electrodes that far apart and for safety and transformer
sake's, I probably won't.

This was a demonstration unit I built some years back. I have it
looking somewhat like a spark coil would look with two adjustable
electrodes on top. Everything is inside PVC junction boxes. It is
never meant to run more than 30 seconds at a time and I have never
exceeded that. I also have quadrac settings for low, medium, and high
output.
 
On Wednesday, October 16, 2019 at 7:04:44 AM UTC-4, Jim Horton wrote:
After letting cool all night in the oven, I pulled out the potted
transformer this morning. I was surprised that some of the wax settled
in the center of the junction box, about 1.5" depression in an area
roughly 1.5" or so wide. It wasn't enough to expose anything, but a
surprise. I was tempted to melt and add more wax to this area today,
but since nothing was exposed, just covered it over with the junction
box cover and was done. Although I could still feel a bit of warmth
coming from the box, I did a quick test after hooking up the driving
circuitry. Sparking is what it should be, just as before with the
mineral oil.

I know others have mentioned doing something like this under vacuum, but
for a budget limited hobbyist like myself, it's pretty much out of the
question. I'm also not sure how I would go about it with hot wax. I do
have a small chamber and single stage pump handy, but those are for
insect drying and nothing the size of this transformer box.

Fun stuff, thanks for sharing your experiences. I was going to suggest
melting the whole thing in a water bath (double boiler), which I remember
from making candles as a kid on the stove top.
But you did that on your own.

George H.
 
On 10/16/19 1:19 PM, George Herold wrote:
On Wednesday, October 16, 2019 at 7:04:44 AM UTC-4, Jim Horton wrote:
After letting cool all night in the oven, I pulled out the potted
transformer this morning. I was surprised that some of the wax settled
in the center of the junction box, about 1.5" depression in an area
roughly 1.5" or so wide. It wasn't enough to expose anything, but a
surprise. I was tempted to melt and add more wax to this area today,
but since nothing was exposed, just covered it over with the junction
box cover and was done. Although I could still feel a bit of warmth
coming from the box, I did a quick test after hooking up the driving
circuitry. Sparking is what it should be, just as before with the
mineral oil.

I know others have mentioned doing something like this under vacuum, but
for a budget limited hobbyist like myself, it's pretty much out of the
question. I'm also not sure how I would go about it with hot wax. I do
have a small chamber and single stage pump handy, but those are for
insect drying and nothing the size of this transformer box.

Fun stuff, thanks for sharing your experiences. I was going to suggest
melting the whole thing in a water bath (double boiler), which I remember
from making candles as a kid on the stove top.
But you did that on your own.

George H.

That's what I ended up doing as it was going to take forever melting the
wax bars in the stove. I didn't have any large coffee cans handy so
picked up Walmart's cheapest coffee only to find that it is cardboard
and not tin. I still used it and amazingly neither the wax ruptured out
or water in, but I don't trust it to use again and will seek a proper
tin can the next time. So the "can" was lowered into a pot of boiling
water. I had to do several meltings, but the oven did keep the poured
wax molten for several hours afterwards and between pourings. I do
regret the depression I found this morning, right in the center of the
wax, but it's small and nothing was uncovered so I put the junction box
cover on, tested it, and all good.

The good news is that the junction box, wiring and even some poly ropes
I use to carry the device around all faired well in the stove at 200 F.
The bad news is how I will ever melt the resulting 6.5 lb wax potted
transformers if I needed to do repairs. Maybe leaving in the stove for
24 hours at 200 F would do the trick, but not sure. I didn't have the
patience to find out if the entire block would melt in the stove or not
this time around.
 
By the way, I'd like to highly recommend QC cleaner:

https://tinyurl.com/y62rcgfn

Whether from Amazon or Walmart, nearly the same price per can. I'd say
it cleaned 99.5% of the mineral oil out of the container and off of the
components and did not leave a residue or smell. It did take 3 cans for
a complete job.
 
On Wednesday, October 16, 2019 at 1:48:29 PM UTC-4, Jim Horton wrote:
On 10/16/19 1:19 PM, George Herold wrote:
On Wednesday, October 16, 2019 at 7:04:44 AM UTC-4, Jim Horton wrote:
After letting cool all night in the oven, I pulled out the potted
transformer this morning. I was surprised that some of the wax settled
in the center of the junction box, about 1.5" depression in an area
roughly 1.5" or so wide. It wasn't enough to expose anything, but a
surprise. I was tempted to melt and add more wax to this area today,
but since nothing was exposed, just covered it over with the junction
box cover and was done. Although I could still feel a bit of warmth
coming from the box, I did a quick test after hooking up the driving
circuitry. Sparking is what it should be, just as before with the
mineral oil.

I know others have mentioned doing something like this under vacuum, but
for a budget limited hobbyist like myself, it's pretty much out of the
question. I'm also not sure how I would go about it with hot wax. I do
have a small chamber and single stage pump handy, but those are for
insect drying and nothing the size of this transformer box.

Fun stuff, thanks for sharing your experiences. I was going to suggest
melting the whole thing in a water bath (double boiler), which I remember
from making candles as a kid on the stove top.
But you did that on your own.

George H.


That's what I ended up doing as it was going to take forever melting the
wax bars in the stove. I didn't have any large coffee cans handy so
picked up Walmart's cheapest coffee only to find that it is cardboard
and not tin. I still used it and amazingly neither the wax ruptured out
or water in, but I don't trust it to use again and will seek a proper
tin can the next time. So the "can" was lowered into a pot of boiling
water. I had to do several meltings, but the oven did keep the poured
wax molten for several hours afterwards and between pourings. I do
regret the depression I found this morning, right in the center of the
wax, but it's small and nothing was uncovered so I put the junction box
cover on, tested it, and all good.

The good news is that the junction box, wiring and even some poly ropes
I use to carry the device around all faired well in the stove at 200 F.
The bad news is how I will ever melt the resulting 6.5 lb wax potted
transformers if I needed to do repairs. Maybe leaving in the stove for
24 hours at 200 F would do the trick, but not sure. I didn't have the
patience to find out if the entire block would melt in the stove or not
this time around.

You could put the whole thing in a water bath in the oven.
The water helps the thermal conductivity into the gizmo.

George H.
 
Jim Horton wrote:
After letting cool all night in the oven, I pulled out the potted
transformer this morning.  I was surprised that some of the wax settled
in the center of the junction box, about 1.5" depression in an area
roughly 1.5" or so wide.  It wasn't enough to expose anything, but a
surprise.  I was tempted to melt and add more wax to this area today,
but since nothing was exposed, just covered it over with the junction
box cover and was done.  Although I could still feel a bit of warmth
coming from the box, I did a quick test after hooking up the driving
circuitry.  Sparking is what it should be, just as before with the
mineral oil.

I know others have mentioned doing something like this under vacuum, but
for a budget limited hobbyist like myself, it's pretty much out of the
question.  I'm also not sure how I would go about it with hot wax.  I do
have a small chamber and single stage pump handy, but those are for
insect drying and nothing the size of this transformer box.

Sounds like it worked!

Paraffin (if that's what you used) tends to shrink considerably as it
hardens. This is likely why you got the depression in the wax. However,
it also continues to shrink if you get it cold and also becomes brittle.
If shrinkage or later cold-cracking causes any air gaps in high E-field
areas, the air in the gaps will ionize, potentially lead to ozone/UV
damage and carbon tracking of insulation.

Old-timers used to mix 1:1 beeswax and rosin when they impregnated mica
capacitors or HV transformer windings. The material shrinks less,
remains relatively soft and tacky, and tends not to pull away from the
embedded objects. The rosin also increases the melting temperature
(beeswax alone melts at just 147 F).

Good luck and play safely!
 

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