Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I won't
be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha (Coleman
fuel), or paint thinner (mineral spirits). Diesel would be about as cheap
as gas, which is a plus, but I am unsure as to it's ability to dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt tar?

Thanks,

Jon

In order of decreasing speed (i.e., fastest first):
naptha
paint thinner
kerosene, diesel

Not all that much difference, though. Go with the cheapest.

Bob

PS acetone would be faster than any of these, but way more expensive.
And just as volatile/dangerous as gas.

Umm - Spell Checker told me it was "naphtha", but I didn't believe it.
Well, it's right & pronounced naf-tha or nap-tha. Learn & learn.

Bob

On Sep 4, 4:24 pm, "Jon Danniken"
wrote:
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I won't
be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha (Coleman
fuel), or paint thinner (mineral spirits). Diesel would be about as cheap
as gas, which is a plus, but I am unsure as to it's ability to dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt tar?

Thanks,

Jon

Hi, Jon.
Are you sure it is asphalt tar? Older transformers I have worked on
were potted in coal tar. Asphalt tar will cold flow and will really
warm flow and make a mess when your transformer gets warm. Coal tar
will not flow until it gets to a rather high temperature. It also
doesn't dissolve in anything very easily. I am not sure if this makes
any difference to you, but you may be able to Goggle a better solvent
for coal tar.

Old radio batteries as well as older auto storage batteries used coal
tar for sealing. It is also now considered a carcinogen and you can't
get it anymore.

Good question, though.

Paul, KD7HB

wrote
Are you sure it is asphalt tar? Older transformers I have worked on
were potted in coal tar. Asphalt tar will cold flow and will really
warm flow and make a mess when your transformer gets warm. Coal tar
will not flow until it gets to a rather high temperature. It also
doesn't dissolve in anything very easily. I am not sure if this makes
any difference to you, but you may be able to Goggle a better solvent
for coal tar.

Well, I'm not entirely too sure, but it melts at about 250F-300F, and smells
like the stuff the roofers use to seal cracks with. .

Jon

On Sep 4, 6:01 pm, "Jon Danniken"
wrote:
... it melts at about 250F-300F, and smells
like the stuff the roofers use to seal cracks with. .

So, you could empty the goo with a drip pan lined with aluminum foil
and
an oven that will hold 300F for twenty minutes. I have at least one
tar brick in the adhesives drawer that I got that way...

whit3rd wrote:

On Sep 4, 6:01 pm, "Jon Danniken"
wrote:
... it melts at about 250F-300F, and smells
like the stuff the roofers use to seal cracks with. .

So, you could empty the goo with a drip pan lined with aluminum foil
and
an oven that will hold 300F for twenty minutes. I have at least one
tar brick in the adhesives drawer that I got that way...

I guess you are not married.




John

Gotta quite drinking beer when I read these! I had to clean up the
keyboard.

John wrote:
whit3rd wrote:
On Sep 4, 6:01 pm, "Jon Danniken"
wrote:
... it melts at about 250F-300F, and smells
like the stuff the roofers use to seal cracks with. .
So, you could empty the goo with a drip pan lined with aluminum foil
and
an oven that will hold 300F for twenty minutes. I have at least one
tar brick in the adhesives drawer that I got that way...

I guess you are not married.




John

Use diesel and prepare to be amazed.


"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I
won't be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha
(Coleman fuel), or paint thinner (mineral spirits). Diesel would be about
as cheap as gas, which is a plus, but I am unsure as to it's ability to
dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt
tar?

Thanks,

Jon

On Tue, 4 Sep 2007 16:24:09 -0700, "Jon Danniken"
wrote:

Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I won't
be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha (Coleman
fuel), or paint thinner (mineral spirits). Diesel would be about as cheap
as gas, which is a plus, but I am unsure as to it's ability to dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt tar?

Thanks,

Jon

Coleman fuel is more volatile than gasoline.


--
Posted via a free Usenet account from http://www.teranews.com

John writes:

whit3rd wrote:

On Sep 4, 6:01 pm, "Jon Danniken"
wrote:
... it melts at about 250F-300F, and smells
like the stuff the roofers use to seal cracks with. .

So, you could empty the goo with a drip pan lined with aluminum foil
and
an oven that will hold 300F for twenty minutes. I have at least one
tar brick in the adhesives drawer that I got that way...

I guess you are not married.

Outside interests are a wonderful thing. Bridge Monday night, concert
band Tuesday... I just have to make sure the smell is gone before she
makes it home.

"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I
won't be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha
(Coleman fuel), or paint thinner (mineral spirits). Diesel would be about
as cheap as gas, which is a plus, but I am unsure as to it's ability to
dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt
tar?

Thanks,

Jon


Stoddard solvent.

Note the word *solvent*.

That's its intended purpose.

Harold

you are doing this backwards - (are you unpotting an NST? if yes, check the
tesla list archives) - put transformer in freezer (or better yet liquid N2)
and get it really cold, then take it out and tap the tar with a hammer - it
will just shatter like glass - get most of it off that way, then use
solvent - others have suggested proper solvents



"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I
won't be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha
(Coleman fuel), or paint thinner (mineral spirits). Diesel would be about
as cheap as gas, which is a plus, but I am unsure as to it's ability to
dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt
tar?

Thanks,

Jon




--
Posted via a free Usenet account from http://www.teranews.com

Sure no science, just age and experience. It seems that things
closer together on the cracking tower dissolve or combine easier
than things far apart on the tower. Diesel would be my first
choice - closer to the tars and asphalts on the tower.

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer
(metal content). In the past when I have done this, I have used
gasoline, which does work. The usual technique is to put the
unit in a bucket of the solvent and let it sit for a few days,
brush off whatever is soft enough, and repeat until a sufficient
amount of tar is removed to allow access to the innards.

Now, however, being somewhat more cautious, I am entertaining
thoughts of using a less volatile solvent, in the interest of
safety. Ideally, I won't be giving up too much solubility in
the process

I have narrowed it down to a few choices, diesel, kerosene,
naptha (Coleman fuel), or paint thinner (mineral spirits).
Diesel would be about as cheap as gas, which is a plus, but I am
unsure as to it's ability to dissolve tar.

Any thoughts on which would be the best solvent for dissolving
asphalt tar?

Thanks,

Jon

On Tue, 4 Sep 2007 21:19:46 -0700, "William Noble"
wrote:

you are doing this backwards - (are you unpotting an NST? if yes, check the
tesla list archives) - put transformer in freezer (or better yet liquid N2)
and get it really cold, then take it out and tap the tar with a hammer - it
will just shatter like glass - get most of it off that way, then use
solvent - others have suggested proper solvents

That works? Damn...fascinating! Thanks!

Gunner, who learns something cool everyday.




"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

Now, however, being somewhat more cautious, I am entertaining thoughts of
using a less volatile solvent, in the interest of safety. Ideally, I
won't be giving up too much solubility in the process

I have narrowed it down to a few choices, diesel, kerosene, naptha
(Coleman fuel), or paint thinner (mineral spirits). Diesel would be about
as cheap as gas, which is a plus, but I am unsure as to it's ability to
dissolve tar.

Any thoughts on which would be the best solvent for dissolving asphalt
tar?

Thanks,

Jon

On Tue, 4 Sep 2007 16:24:09 -0700, "Jon Danniken"
wrote:
snip
In the past when I have done this, I have used gasoline, which
does work.
snip
It is well to remember that there is no single compound that is
"gasoline." Over the years it has changed from a totally
petrolium distilate with possibly a littleTEL to a witches brew.

I also used to use gasoline to clean parts, but had some a few
months ago that took skin off my hands and nearly removed some of
the nails.

I don't thnk the major danger is the volitility, which based on
hard starting may even be less than the old (real) "gasoline,"
but the (toxic?) fumes and danger to your hide.

With naptha/paint thinner/varsol you at least know what you are
getting.


Unka' George [George McDuffee]
============
Merchants have no country.
The mere spot they stand on
does not constitute so strong an attachment
as that from which they draw their gains.

Thomas Jefferson (1743-1826),
U.S. president. Letter, 17 March 1814.

On Tue, 04 Sep 2007 21:42:20 -0400, John
wrote:

whit3rd wrote:

On Sep 4, 6:01 pm, "Jon Danniken"
wrote:
... it melts at about 250F-300F, and smells
like the stuff the roofers use to seal cracks with. .

So, you could empty the goo with a drip pan lined with aluminum foil
and
an oven that will hold 300F for twenty minutes. I have at least one
tar brick in the adhesives drawer that I got that way...

I guess you are not married.

Some of us have a stove/oven in our shops for this very reason... to
stay married g. I've even got m' own washer/dryer in here too.

Snarl

John wrote:

I guess you are not married.

Use the oven and he might not be....

F. George McDuffee wrote:

On Tue, 4 Sep 2007 16:24:09 -0700, "Jon Danniken"
wrote:
snip

In the past when I have done this, I have used gasoline, which
does work.

snip
It is well to remember that there is no single compound that is
"gasoline." Over the years it has changed from a totally
petrolium distilate with possibly a littleTEL to a witches brew.

I also used to use gasoline to clean parts, but had some a few
months ago that took skin off my hands and nearly removed some of
the nails.

I don't thnk the major danger is the volitility, which based on
hard starting may even be less than the old (real) "gasoline,"
but the (toxic?) fumes and danger to your hide.

With naptha/paint thinner/varsol you at least know what you are
getting.


Unka' George [George McDuffee]
============
Merchants have no country.
The mere spot they stand on
does not constitute so strong an attachment
as that from which they draw their gains.

Thomas Jefferson (1743-1826),
U.S. president. Letter, 17 March 1814.




Aviation gas... They cant screw with that too much. The last time
they did was when they went to 100LL. It doesn't leave a smell after
it evaporates, just a little lead and it takes the oils out o your skin.

John

"Bob Engelhardt" wrote:

In order of decreasing speed (i.e., fastest first):
naptha
paint thinner
kerosene, diesel

Not all that much difference, though. Go with the cheapest.

Thanks, Bob, and everyone else as well; looks like diesel will be my weapon
of choice this round.

Jon

On Sep 5, 12:13 am, Bob Engelhardt wrote:
In order of decreasing speed (i.e., fastest first):
naptha
paint thinner
kerosene, diesel

Not all that much difference, though. Go with the cheapest.


There may not be much difference in effectiveness
as a solvent, but there is a big difference in safety.

Naphtha and paint thinner have flashpoints down
near or below room temperature. The measured
flashpoint of a liquid is the temperature at which
the vapors above the liquid can be ignited by an
open flame. In theory (I think) this is exactly the
same temperature as the temperature at which the
partial pressure of the vapor divided by total
pressure will equal the lower inflammable limit.

Kerosene and diesel fuel have higher flashpoints
and so will not form an explosive atmosphere at
room temperature unless they are atomized.

The distinction between an inflammable liquid
and a combustible liquid is based on flashpoint.
ISTR 140 Fahrenheit as dividing the two.

If you are using an open container of an
inflammable liquid like gasoline,
paint thinner, acetone or naphtha near
an open flame like a pilot light that may be
the last mistake you ever make.

Doing the same with a liquid that is
merely combustible is not a great idea,
but very unlikely to be as exciting.


PS acetone would be faster than any of these, but way more expensive.
And just as volatile/dangerous as gas.

One problem with using acetone to clean gunk is
that it evaporates so fast that it is hard to keep
the part wetted.

I think that acetone has a rather low heating value
so that when it goes boom, it is not quite as bad
as gasoline.

But I'd rather not test that.

Chlorinated solvents tend to be nonflammable.
They give you cancer and destroy the ozone
layer instead.

--

FF

"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

I've discovered over the years that you can substitute lots of solvent
($$) for taking advantage of how the solvents work.
What I mean is that when I have a thick goo I need to dissolve, I put a
rag soaked in solvent on top of/around the goo, and wrap the rag in plastic
or some other way to seal it up from excessive vapor loss. Go away for a
little while (you'll learn how much eventually) and when you come back it's
a whole lot easier to get off than before. In fact, I have a tub that has a
bunch of old towels in the bottom of it. When I need to clean/strip painted
items, I put parts in the tub on the towels, previously soaked in acetone or
other favorite solvent, then close the tub up for awhile. Come back the
next time I feel like working on it, and the paint falls off in sheets with
little or no effort. Works the same way for any other stuff that can be
affected by a solvent.
You can work hard, or you can work smart. Me, I'm a bit lazy.

On Wed, 5 Sep 2007 15:40:32 -0700, with neither quill nor qualm, "Carl
McIver" quickly quoth:

"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

I've discovered over the years that you can substitute lots of solvent
($$) for taking advantage of how the solvents work.
What I mean is that when I have a thick goo I need to dissolve, I put a
rag soaked in solvent on top of/around the goo, and wrap the rag in plastic
or some other way to seal it up from excessive vapor loss. Go away for a
little while (you'll learn how much eventually) and when you come back it's
a whole lot easier to get off than before. In fact, I have a tub that has a
bunch of old towels in the bottom of it. When I need to clean/strip painted
items, I put parts in the tub on the towels, previously soaked in acetone or
other favorite solvent, then close the tub up for awhile. Come back the
next time I feel like working on it, and the paint falls off in sheets with
little or no effort. Works the same way for any other stuff that can be
affected by a solvent.
You can work hard, or you can work smart. Me, I'm a bit lazy.

Verily. I learned that with water. I spray it on dirty items and walk
away. Five or ten minutes later, the water-soluble dirt wipes right
off. I then spray with solvent, walk away, and wipe the rest of the
water-insoluble goo off in a few minutes. It sure beats scrubbing for
half an hour, doesn't it?

================================================== =========
Save the Endangered Bouillons from being cubed!
================================================== =========

Carl McIver wrote:

"Jon Danniken" wrote in message
...
Howdy,

I need to dissolve some asphalt potting tar off of a transformer (metal
content). In the past when I have done this, I have used gasoline, which
does work. The usual technique is to put the unit in a bucket of the
solvent and let it sit for a few days, brush off whatever is soft enough,
and repeat until a sufficient amount of tar is removed to allow access to
the innards.

I've discovered over the years that you can substitute lots of solvent
($$) for taking advantage of how the solvents work.
What I mean is that when I have a thick goo I need to dissolve, I put a
rag soaked in solvent on top of/around the goo, and wrap the rag in plastic
or some other way to seal it up from excessive vapor loss. Go away for a
little while (you'll learn how much eventually) and when you come back it's
a whole lot easier to get off than before. In fact, I have a tub that has a
bunch of old towels in the bottom of it. When I need to clean/strip painted
items, I put parts in the tub on the towels, previously soaked in acetone or
other favorite solvent, then close the tub up for awhile. Come back the
next time I feel like working on it, and the paint falls off in sheets with
little or no effort. Works the same way for any other stuff that can be
affected by a solvent.
You can work hard, or you can work smart. Me, I'm a bit lazy.



That is the basic priciple of many paint strippers. You apply the jelly
like stripper to the surface and it forms a skin over it and holds the
stripper to the surface so it doesn't evaprate. That is why they
instruct you not to disturb the surface once you apply it.


John

After a Computer crash and the demise of civilization, it was learned
Fred the Red Shirt wrote on Wed, 05 Sep 2007
13:56:28 -0700 in rec.crafts.metalworking :

The distinction between an inflammable liquid
and a combustible liquid is based on flashpoint.
ISTR 140 Fahrenheit as dividing the two.

If you are using an open container of an
inflammable liquid like gasoline,
paint thinner, acetone or naphtha near
an open flame like a pilot light that may be
the last mistake you ever make.

Doing the same with a liquid that is
merely combustible is not a great idea,
but very unlikely to be as exciting.

Oh I don't know. Something which catches fire is exciting. Something
which kills you dead right off, you don't have time to be "excited". :-)

But good points on the safety issues


tschus
pyotr

--
pyotr filipivich
"Quemadmoeum gladuis neminem occidit, occidentis telum est. "
Lucius Annaeus Seneca, circa 45 AD
(A sword is never a killer, it is a tool in the killer's hands.)

After a Computer crash and the demise of civilization, it was learned
"William Noble" wrote on Tue, 4 Sep 2007 21:19:46
-0700 in rec.crafts.metalworking :
you are doing this backwards - (are you unpotting an NST? if yes, check the
tesla list archives) - put transformer in freezer (or better yet liquid N2)

Umm, have you priced N2 in liquid form? I've heard "it is cheap as
beer" but they never say what kind of beer: Sludgwillers or a microbrew.
But it was real neat when I poured the excess into my travel mug - sent
a plume of fog out the opening. Cool enough I'm almost willing to go
back over to assembly. Almost.

But the freezer trick is a cool alternative.


pyotr

--
pyotr filipivich
"Quemadmoeum gladuis neminem occidit, occidentis telum est. "
Lucius Annaeus Seneca, circa 45 AD
(A sword is never a killer, it is a tool in the killer's hands.)

replying to Jon Danniken, Dell wrote:
Hello can anyone tell me what chemicals could have burnt this tarmac of the
path my dog died after getting whatever it was help i thought it was some sort
of acid the council say its not acid i do

https://www.polytechforum.com/img/6w
https://www.polytechforum.com/img/6x
https://www.polytechforum.com/img/6y
https://www.polytechforum.com/img/6z