Speaking of tack welds

Bob La Londe

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Jul 17, 2008, 4:00:46 PM7/17/08

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I was recently watching all those mig welding video shorts on the Miller
website that Ernie turned us onto. I noticed that theyrecommended a tack
weld every so many inches, and then go back and make your weld. In the past
I have always made the absolute minimum number of tacks to hold the piece in
place because I found it hard to get a nice continuous bead through the tack
welds placed for holding the materials. Is there a trick to that or do you
just stop when you hit the tack and then try to flow into it on the other
side to restart your bead? Even with flux core or gas I've found the
hardest part of a weld (for me) to get just right is where you start.

Bob
www.YumaBassMan.com

Bob La Londe

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Jul 24, 2008, 2:46:24 PM7/24/08

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I'm still trying to figure out the best way to deal with tac welds.

Do you just weld through them? Stop and start again on the other side?

Grant Erwin

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Jul 24, 2008, 3:12:09 PM7/24/08

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Bob La Londe wrote:

> I'm still trying to figure out the best way to deal with tac welds.
>
> Do you just weld through them? Stop and start again on the other side?
>
>

Bob, it depends entirely what you are welding. Lots of times I assemble a
weldment with a lot of little tacks and then if a seam is important and it
is sufficiently held by all the other tacks and welds and if cutting the
tacks won't make anything move, then I'll grind out the cracks. But that
significantly increases labor costs so generally I weld over them but move
a little faster so the resulting bead is more even. You don't want the
watermelon-in-a-snake look. Practice watching the puddle, which can be
tricky when MIG welding with that bigass nozzle in the way.

Grant

Bruce in Bangkok

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Jul 24, 2008, 8:41:31 PM7/24/08

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On Thu, 24 Jul 2008 11:46:24 -0700, "Bob La Londe" <nos...@nospam.no>
wrote:

>I'm still trying to figure out the best way to deal with tac welds.
>
>Do you just weld through them? Stop and start again on the other side?
>

Generally, depending of course on the size of the Tacs, you can weld
over them. If you are aiming at X-Ray quality welds then it is normal
to grind out each tac as you come to it.

Bruce-in-Bangkok
(correct Address is bpaige125atgmaildotcom)

SteveB

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Jul 25, 2008, 2:34:29 AM7/25/08

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>
>>I'm still trying to figure out the best way to deal with tac welds.

What is it exactly you are welding?

Steve

Bob La Londe

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Jul 25, 2008, 11:03:39 AM7/25/08

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"SteveB" <toquerville@zionvistas> wrote in message
news:4m1ol5-...@news.infowest.com...

>
>
>>
>>>I'm still trying to figure out the best way to deal with tac welds.
>
> What is it exactly you are welding?

Hypotheticals.

Grant Erwin

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Jul 25, 2008, 12:14:52 PM7/25/08

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Oh, those are different. Ignore everything.

Bob La Londe

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Jul 25, 2008, 1:25:05 PM7/25/08

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"Grant Erwin" <gr...@NOSPAMkirkland.net> wrote in message
news:0_mik.5$JH5.2@trnddc06...

Yeah, the nice thing about those is you can put 'em together anyway you
want.

SteveB

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Jul 25, 2008, 4:48:37 PM7/25/08

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"Bob La Londe" <nos...@nospam.no> wrote in message
news:g6cr54$f0h$1...@aioe.org...

Are they going to be x rayed or NDT?

I'd say for me it has a lot to do with the final weld requirements, the
inspector, the specs, and the day of the week. Sometimes you can grind them
a bit, and then make them molten again as you run through them. But then,
sometimes that makes them crack before you get there.

BTW, what kind of rod would you use for that?

Steve