Is there a chemical method to removing mill scale? I'm working with 14ga and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone &
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

On Sun, 27 Feb 2005 10:49:08 -0700, "TT" wrote:

Is there a chemical method to removing mill scale? I'm working with 14ga and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone &
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick or
will I need something harsher?

Blasting with glass beads removes mill scale very nicely. However,
you may get a bit of distortion on steel as thin as 14 gage. Walnut
shells are less likely to cause distortion, but I don't know if
they're aggressive enough to remove mill scale.

Muriatic acid will do the job.

The metal must be protected (painted or clearcoated) very soon after
blasting or acid stripping, or it will rust.

On Sun, 27 Feb 2005 10:49:08 -0700, "TT" wrote:

Is there a chemical method to removing mill scale? I'm working with 14ga and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone &
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

I've asked the same question. The answer: A solution of vinegar and
salt. Use excess salt. Dissolve as much as you can in the vinegar.
If done right there'll be a layer of it in the bottom of the
container.

Regards,

Orrin

Sorry, I should have googled google's groups archive before asking this
question.

I will surely try the vinegar or vinegar / salt solution.

Thanks and sorry, no more responses needed.

-Tom

"TT" wrote in message
news:uKnUd.13376$Az.3676@lakeread02...
Is there a chemical method to removing mill scale? I'm working with 14ga
and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone
&
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick
or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

Had the same problem until I started ordering sheets without slag a few more
bucks and well worth it. Replaced my SB cabinet this week with large
version from HF retail on sale $199.00 an excellent buy thifty on air at
about 9 cfm. Try carbide blasting slag excellent for powder coating about
1/5th the cost of glass beads.

Ken

"TT" wrote in message
news:uKnUd.13376$Az.3676@lakeread02...
Is there a chemical method to removing mill scale? I'm working with 14ga
and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone
&
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick
or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

Not challenging the muriatic acid and vinegar/salt suggestions, just
surprised that such mild chemical treatments would have any effect, at least
w/ some of the HR scale I see.
That scale, IIUC, is a kind of oxidation product, and thus pretty stable.
The underlying steel itself is *much more* reactive to different breeds of
acids, such as nitric, which is probably not available to consumers anyway,
not just because of 9/11, but because it is pretty nasty stuff.
The suggestions tho are certainly cheap enough to try.

It's interesting that different steels from different plants have really
diff. appearances.
I remember buying a bit of HR angle iron (approx. 1" x 1/8) that happened to
be from Korea at the time.
Mills bad-mouthed it alloy-wise, but let me tell you, it had an inside
radius of *near-zero*, like arch. alum, w/ zero scale! Had sort of a
reddish color, which is how you knew it wasn't cold rolled, also was
grainier than CR. Straight and nice.
Some of the crap I see today... goodgawd....

Cold-rolled is a nice option, albeit at extra cost, but might be worth the
extra $$, depending on how difficult scale removal actually is.

Just in case the OP is still reading....
----------------------------
Mr. P.V.'d
formerly Droll Troll
"Orrin Iseminger" wrote in message
...
On Sun, 27 Feb 2005 10:49:08 -0700, "TT" wrote:

Is there a chemical method to removing mill scale? I'm working with 14ga
and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone
&
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick
or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

I've asked the same question. The answer: A solution of vinegar and
salt. Use excess salt. Dissolve as much as you can in the vinegar.
If done right there'll be a layer of it in the bottom of the
container.

Regards,

Orrin

Oh yeah, forgot to mention, lest the other suggestions don't pan out,
running flat material through a "time saver" (basically a big stationary
self-feeding belt sander) will give miraculous results, even a polish w/ the
right grits. Pricey machines ($3K used, smallish), not a lot of shops have
them.

If the material is suff'ly narrow, you could kluge your own time-saver w/ a
4" belt sander, something I'm eventually going to have to do.
----------------------------
Mr. P.V.'d
formerly Droll Troll
"Proctologically Violated©®" wrote in message
...
Not challenging the muriatic acid and vinegar/salt suggestions, just
surprised that such mild chemical treatments would have any effect, at
least w/ some of the HR scale I see.
That scale, IIUC, is a kind of oxidation product, and thus pretty stable.
The underlying steel itself is *much more* reactive to different breeds of
acids, such as nitric, which is probably not available to consumers
anyway, not just because of 9/11, but because it is pretty nasty stuff.
The suggestions tho are certainly cheap enough to try.

It's interesting that different steels from different plants have really
diff. appearances.
I remember buying a bit of HR angle iron (approx. 1" x 1/8) that happened
to be from Korea at the time.
Mills bad-mouthed it alloy-wise, but let me tell you, it had an inside
radius of *near-zero*, like arch. alum, w/ zero scale! Had sort of a
reddish color, which is how you knew it wasn't cold rolled, also was
grainier than CR. Straight and nice.
Some of the crap I see today... goodgawd....

Cold-rolled is a nice option, albeit at extra cost, but might be worth the
extra $$, depending on how difficult scale removal actually is.

Just in case the OP is still reading....
----------------------------
Mr. P.V.'d
formerly Droll Troll
"Orrin Iseminger" wrote in message
...
On Sun, 27 Feb 2005 10:49:08 -0700, "TT" wrote:

Is there a chemical method to removing mill scale? I'm working with 14ga
and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc
to
desired finish. Among other problems is that heat generated from the
stone &
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick
or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

I've asked the same question. The answer: A solution of vinegar and
salt. Use excess salt. Dissolve as much as you can in the vinegar.
If done right there'll be a layer of it in the bottom of the
container.

Regards,

Orrin

TT wrote:

Is there a chemical method to removing mill scale?

Anyone know of a chemical method? How about muriatic acid?

-Tom

Yes. H Cl ( hydrochloric ) ( Muriatic ) acid works fine.
Just did a bunch of small parts at school. The kind sold
in the "big box" stors as concrete cleaner, it takes a while
to work but does a good job.
...lew...

Whaddya know?! The vinegar & salt trick worked.

Soaked for about 12 hours and the mill scale came off with a nylon scrubbing
brush.

Awesome.

-Tom

"TT" wrote in message
news:uKnUd.13376$Az.3676@lakeread02...
Is there a chemical method to removing mill scale? I'm working with 14ga
and
removing mill scale is just time consuming and generally not a fun job. I
hit it with a stone disc to get the majority of it off & then flapdisc to
desired finish. Among other problems is that heat generated from the stone
&
flapdiscing will sometimes warp the piece.

Anyone know of a chemical method? How about muriatic acid? Do they make a
"stripper" chemical for steel?

Alternatively, I hope to buy a blasting gun & cabinet soon, what kind of
media should I use to remove mill scale? Would walnut shells do the trick
or
will I need something harsher?

Thanks to those who responded to my clearcoating question.

-Tom

On Sun, 27 Feb 2005 18:39:18 -0800, Orrin Iseminger
wrote:


I've asked the same question. The answer: A solution of vinegar and
salt. Use excess salt. Dissolve as much as you can in the vinegar.
If done right there'll be a layer of it in the bottom of the
container.

Regards,

Orrin



Orrin,

What concentration of vinegar do you suggest? Up here in Canada, the
most common is 5%, although I suppose if a fella looked hard enough,
he could find higher concentrations.


Intrepid

[Vinegar] Up here in Canada, the
most common is 5%
although I suppose if a fella looked hard enough,
he could find higher concentrations.

At higher concentrations of the active ingredient it'll be called
"acetic acid". At high enough concentrations, "glacial acetic acid".

But doing higher concentrations won't help much in getting rid of rust.
Go straight for muriatic acid.

Tim.

On 2 Mar 2005 06:33:56 -0800, "Tim Shoppa"
wrote:

[Vinegar] Up here in Canada, the
most common is 5%
although I suppose if a fella looked hard enough,
he could find higher concentrations.

At higher concentrations of the active ingredient it'll be called
"acetic acid". At high enough concentrations, "glacial acetic acid".

But doing higher concentrations won't help much in getting rid of rust.
Go straight for muriatic acid.

Tim.
Personally I use Citric Acid, available from your local drug store or
homebrew outfit.
AND you can legally pour it down the drains afterwards without the
local municipality breathing down your neck.
Mike in BC

On Wed, 02 Mar 2005 06:48:27 -0600, Intrepid wrote:



What concentration of vinegar do you suggest? Up here in Canada, the
most common is 5%, although I suppose if a fella looked hard enough,
he could find higher concentrations.


Intrepid
AFAIK the regular 5% stuff works just fine. If you would like to spend
more money, go ahead and buy the 7% pickling vinegar, it might even
work a bit faster - I'm not in that much of a hurry. One thing to
remember in this process, springs tend to come out in multiple, small
pieces.
Gerry :-)}
London, Canada