welding 'paintlock' sheet metal

[Roger Hull]

The last time I bought sheet metal my choices were Galvanized and Paintlock.
I am cutting small pieces and spot welding (electric resistance) them
together. I chose the Paintlock after the salesman told me it would not
interfere with spotwelding. He fibbed.... I've tried soaking in Acetone,
sandblasting, wire-wheeling and an angle grinder with sanding disks. The
angle grinder is the only one that worked worth a darn in removing this crap.
I don't think it is a coating, but rather a surface treatment of some sort.

Does anyone know another way to make this stuff weldable?

Thanks.

[Peter T. Keillor III]

On Mon, 3 May 2004 16:29:31 -0700, Roger Hull <rh...@velocitus.net>
wrote:

Apparently, Paintlock is galvanized with a surface treatment so paint
will stick better. See link:
http://www.herculesindustries.com/products_catalog_Request2.asp?txtid=275

Hydrochloric will remove it, but it'll rust shortly after unless you
rinse and neutralize. Look for threads on rust removal. I've
recently been getting black (uncoated) steel from the local sheet
metal shop, any gauge I need.

I just got some powder coated latches I intend to weld on. the
oxyacetylene torch reduced the coating to ash in short order.

Good luck,

Pete Keillor

[SteveB]

"Roger Hull" <rh...@velocitus.net> wrote in message
news:0001HW.BCBC23EB...@nntp.velocitus.net...

Weird. I just made a pan for my washing machine when I relocated it. About
28" square with 4" sides. Bent at the right points, then welded the seams
together. It is 22 ga, and it spot welded with my Lincoln 175SP+ easily by
spotting. A little touch up with an electric wire brush, and then painted
it.

Steve

[Dan Harlan]

replying to Roger Hull, Dan Harlan wrote:

Galvannealed (which PaintLok is a type of, specifically ASTM A653 Coating
A60) is very similar to Galvanized except it uses a zinc-iron alloy rather
than just zinc. Both are per ASTM A653, with galvannealed being a coating
designation of A or ZF and galvanized a G or Z designation.

Electro-Galvanized (ASTM A879) is another variant of corrosion resistant
steel sheet.

Both Galvannelaed and Electro-Galvanized are readily formable and weldable
with no need to remove the coating. Both accept paint well.

Normal Galvanized (ASTM A653 any coating G or Z) does not accept paint
well.

Some commercial references:
http://www.hbsteel.com/galvanized-steel-sheets.html
https://www.industrialmetalsupply.com/Metal-Resources/Metal-Glossary

~Dan

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[SteveB]

On 1/27/2014 8:18 PM, Dan Harlan wrote:
> replying to Roger Hull, Dan Harlan wrote:
>> rhull wrote:
>>
>> The last time I bought sheet metal my choices were Galvanized and
> Paintlock.
>> I am cutting small pieces and spot welding (electric resistance) them
>> together. I chose the Paintlock after the salesman told me it would
>> not interfere with spotwelding. He fibbed.... I've tried soaking in
>> Acetone, sandblasting, wire-wheeling and an angle grinder with sanding
>> disks. The angle grinder is the only one that worked worth a darn in
>> removing this
> crap.
>> I don't think it is a coating, but rather a surface treatment of some
>> sort.
>> Does anyone know another way to make this stuff weldable?
>> Thanks.
>

I use a lot of paintlock for various purposes. I have never ever had a
problem welding it. I use a Miller 180. I use various wire. As any
good welder does, I cut coupons, and trial weld them. I have built a
large assortment of items out of paint lock, and other than burn
through, have not had a problem welding it.

The main thing is setting the heat setting, and using spot welding,
rather than trying to run a line. Or for me, that is. A series of
spots can be very attractive, looking like TIG, and very strong. I have
none of the white hairy film like galvanized.

As I said, fitup, heat settings, and getting the sequence and timing of
spot welding is the key to me. I do rosette weld in a lot of places
where it is advantageous to have a nice tight fit for the paintlock to
lay against the parent metal.

In rereading this, I see electric resistance welding. Might MIG serve
your purposes better, perhaps drilling a rosette hole in one piece,
hence giving you an almost flush finished weld on both sides. After a
few practice runs, that is.


Steve