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Parent - - By Northweldor (***) Date 02-02-2013 13:25 Edited 02-02-2013 13:30
Ron:
Could you elaborate a bit on using HF with SMAW for starts? Is this built into the machine or is it a variety of  add-on, like this (which I had dismissed as snake-oil)?

http://arcpig.com/howitworks.html
Parent - - By RonG (****) Date 02-04-2013 04:46
Ron, Out machines have a switch that allows you turn the Hi-Freq start on or off. It works in SMAW just like in the GTAW mode. Once the arc is estblished it turns its self off.

Back in the days of the early POWCON inverter machine I had a Hobart Hi-Freq box attached to it that served the same purpose. It made a high pitched buzz in the GTAW mode (at the torch) but not in SMAW mode (the Powcon not the Hi-Freq box). Not sure about the spelling for the Powcon been around 20 years ago.
Parent - - By Northweldor (***) Date 02-04-2013 12:04 Edited 02-04-2013 12:06
Thanks for the information, and it seems that there is a legitimate purpose for HF in SMAW, beyond the revival of old technology that the ArcPig and similar devices represent. I also remember the old Century/Sears HFs and I think there are some of these still around, as well as some very old Powcons! I wonder if the add-ons like the Miller HF251 and others, permit use of HF in SMAW as a choice for arc starting?
Parent - By 357max (***) Date 02-07-2013 16:22
These high frequency arc starters/generators were originally designed to be used for AC SMAW. The limited wattage AC (ie "buzz boxes") transformer welders produced a low open circuit voltage output (as low as 40 volts dependent on the primary voltage - low primary lower ocv or higher primary higher ocv.) The electrodes used required a higher ocv to maintain the arc. Therin was the need for high frequency high voltage. This can be proven by using high frequency high voltage on continuous when welding with the E6010 or E7015 with alternating current.
A lot of the high frequency high voltage units were sold as add ons for SMAW & they evolved into arc starters and arc stabilizers for GTAW. Some like the Century & Forney had it built in the machine.
It has also been used as an arc starter for SAW.
And yes if the SMAW electrode holder is not well insulated it will tingle! If someone has the OSHA Manual, does it prohibit the use of High Friequency High Voltage for SMAW?
Parent - - By welderbrent (*****) Date 02-02-2013 14:24 Edited 02-02-2013 17:16
I'm 'curious' as well Ron.  (edit: I guess we should include Dave in this question as well based upon one of his earlier posts responding to my questions)

Based upon Henry's and Lawrence's comments I have questions.  Now, I know our GTAW machine, which will also weld SMAW, has a setting for the GTAW that is HF at 'start' only.  Makes the initiating of the arc cleaner and saves tungsten.  But, are you applying this to SMAW?  And by what research or PQR's is it supported?  Or, are we talking about very special electrodes?  You mention a 'Fiberglass' sleeve? 

I also ask this wondering if there is still some misunderstanding as Lawrence pointed out between HF and inverters.

Have a Great Day,  Brent

edit: I should have clarified, the 'start only' setting is used when on GTAW-EN (EP also if you want to use it for some reason) on carbon steel or others when set thus.  So, the question becomes, can it be used when using this machine for SMAW as well?  Hope that makes my first paragraph easier to understand.
Parent - - By Lawrence (*****) Date 02-02-2013 15:25
Me too... I wanna hear more after blabbing myself about how dangerous this kind of operation is.

Also... Please post pics of the setup!

I'm very interested in how this works
Parent - - By ssbn727 (*****) Date 02-02-2013 22:39 Edited 02-02-2013 22:41
Larry,

You weren't blabbing at all pal! Like myself, you weren't aware that there was a new product/gadget available that could safely produce super-imposing HFon just about any CC welding power source... Remember that this isn't recommended to be used with CV type power sources or GMAW/FCAW processes...

Now, this gadget does have a whole bunch of potential for use in locations where access is limited, and other worthy applications as well but, $500 is a bit steep in my book!!!
I mean for that amount, you would expect to have a better cooling fan at the very least!!!

I am also very skeptical about the robustness of the ferrite rod which in itself is brittle enough to easily crack and fall apart with not too much effort... A three foot fall onto concrete??? C'mon MAN??? For $500 one would think of buying something more robust so it would last longer and have a better warranty that what the "Arc Pig" offers regardless if it's made in Texas, Arizona, Canada or Pennsylvania!!!

Nope! I'll wait for a better designed version before I lay out 5 "saw bucks" for something that is limited in it's application when compared to a traditional HF transformer circuit or even better, a well made adjustable square wave output power source like a Miller Dynasty which also happens to be an inverter type power source where one doesn't even need super-imposed HF to start or maintain their arcs!!!:eek::roll::lol::wink::cool:

Here's the link to the user's manual for the "Arc Pig":

http://arcpig.com/arc_pig_user_manual.pdf

You'll definitely find it interesting indeed Larry. :wink::cool:

Respectfully,
Henry
Parent - - By Lawrence (*****) Date 02-02-2013 23:10
Excerpt from Arc Pig owners Manual:

"Nevertheless, welding is not
safe, and the Pig may become
hazardous due to malfunction or design flaw. We promise only
that the Pig's designer uses a Pig himself, and rarely bothers to
wear gloves. But he might be an idiot."

Let's try this one together Henry.... I'll hold your beer   :)
Parent - By ssbn727 (*****) Date 02-02-2013 23:16
:eek::yell::grin::lol::grin::lol::wink::cool::cool::cool:
Parent - - By RonG (****) Date 02-03-2013 21:33 Edited 02-03-2013 21:44
The Hi-Freq is as suggested a start only switch selection and we use it very often. No it is not an essential variable and does not affect the weld. What we do in our shop is repair, but the procedures comes from our manufacturing facility. The procedure is qualified exactly as the WPS instructs.

After putting a Fiber glass sleeve that fits snug on the electrode we bend the electrode because we are working in narrow slot (sometimes 1/2" wide x 3"-4" long, welding vanes to the side plates of Compressor Impellers (we call them wheels). We must follow the involute  contour of the vane starting deep in near the ID and working out to the OD.

The Fiberglass sleeve does not affect the weld.

Electrodes are from ER630, ER309L, ER90 & 12018. Wheels 17-4PH, 300SS HY80-100.
Parent - By Lawrence (*****) Date 02-04-2013 04:56
That's pretty cool Ron.

It makes good sense for what you do..

Still wanna see pics... (if it's not propiatary tech)

  Someday somebody else is gonna ask about this  :)
Parent - By DaveBoyer (*****) Date 02-04-2013 05:40
I knew of using HF start with SMAW by having read about it, not by actually seeing it done. I had, and still have some safety concerns.
Parent - By Lawrence (*****) Date 01-31-2013 04:46
GMAW  voltage is *constant*   Circuit open or closed... short circuiting or spray..  

GMAW/FCAW Current varies... Not voltage   #1

GTAW uses HF to avoid touching electrode to work...   Higher open circuit voltage (GTAW or SMAW) to push current across a cold (less ionized gap)    For GTAW the help is HF... For SMAW the help is touching the electrode to the work.

SMAW requres higher voltage than GMAW at arc initiation because the gap between an SMAW electrode and the work before the arc is struck is #air#... GMAW has a gas shield that once the energized electrode wire hits the work will ionize and make an easy path for the arc. 

SMAW open circuit votlage commonly  50-90 volts

GTAW open circuit voltage   slightly less

GMAW FCAW... Constant voltage set by the operator...
- - By deisel (*) Date 01-31-2013 11:58
o so the main reason it uses the high frequency other than avoiding rectification is to preserve the tungsten and keep it from contaminating the weld by avoiding contact with the base metal, right? So it would not serve a purpose in GMAW or FCAW becuase they already have the cover gas pushing air and everything out of the way so the arc can ignite easily.
Parent - - By Lawrence (*****) Date 01-31-2013 15:51
**** <----stars
Parent - - By welderbrent (*****) Date 01-31-2013 16:02
She needs to advance to engineering school.  This girl's mind will be wasted on welding.  It's the desire to ask questions, find answers, and explore the entire realm of the work that will take her far, if she so desires.

Have a Great Day,  Brent
Parent - - By Lawrence (*****) Date 01-31-2013 16:20 Edited 01-31-2013 16:22
She has heard those words before Brent  :)

We have a baby pipeline going into Ferris State... But are working hard to get more students to think about that.

Believe me... If there were more welding engineers in my portion of the midwest, profits, jobs, and economy would boom!

So many manufacturers just don't do things the best way.....  Even the CWS curriculum, if implemented would leverage huge gains in production and value...

I just love when folks are interested in process control.

But don't push her into engineering school too fast... I have a new Lincoln Flex-Tec 650 that was donated to the school and she is going to fabricate a cart for it....  :)
Parent - - By deisel (*) Date 02-03-2013 02:00
What other schools are there besides ferris? I wil be researching but I was wondering what schools all of you went to.  I don't think I'm cut out for engineering, my pockets aren't deep enough and I'm terrible at math,  but I'd like to look into it. Just in case.
Parent - - By OBEWAN (***) Date 02-03-2013 09:44 Edited 02-03-2013 09:55
There are many choices, but I don't know about your geographic area.  If you have to go away for school you will need to consider the cost of housing as well as tuition.  Some of the short trade schools can be quite expensive compared to the value of a good community college program.  Another option that would pay while learning is the military.  The education tab at this website has a welding schools database that has a ton of useful information.  I graduated from the 4 year welding engineering technology program at LeTourneau University in Longview, TX.  They do not have any certificate programs at present though.  I got a BS degree for about $14,000 in 1981 including housing, meals, books, and tuition. But now, due to inflation, their cost is around $18,000-$20,000 a year.  But, back then the minimum wage was a lot less than it is now.  I was able to get jobs in the summer as welder and QC inspector, and all my expenses were covered.  I graduated with no debts, 5 job offers, and $600 in the bank.  There was a huge recession and high unemployment at the time, but there was a huge oil boom in Texas with millions of people from Michigan and Ohio moving south to find work in the oil industry.

AWS Database:
http://www.aws.org/w/e/

Army, Navy, AirForce, Marines:
http://www.careersinthemilitary.com/index.cfm?fuseaction=main.careerdetail&mc_id=53

Excellent Article:
http://www.weldmyworld.com/blog/2011/05/welding-careers-in-the-military.html

Navy may be best (ship, nuke, and aircraft welding):
http://www.ehow.com/list_6531439_navy-welding-careers.html

Discussion forum
http://answers.yahoo.com/question/index?qid=20080426155651AAjbxPC
Parent - - By deisel (*) Date 02-03-2013 16:18
I can't go the military route because I'm disabled.  I'll look into the school in Texas, I've always liked that region. I'm from Illinois but I'm living in Wisconsin for college, Larry is my teacher. From what I've heard there aren't any very close schools for welding engineering.
Parent - By Northweldor (***) Date 02-03-2013 18:06 Edited 02-03-2013 18:38
What about just across the northern border:grin:?

http://www.cwa-acs.org/weldinginstitutions.html#ON
Parent - By OBEWAN (***) Date 02-03-2013 18:24
Don't let the math scare you.  I was not a whiz in high school, but then with some hard study I managed to get my grades up.   And, in college I got by with B's and C's in algebra and calculus.  If you go with the technology program, the welding courses are mostly about materials testing and metallurgy theory.  And, on the job, we use computers to do all the heavy lifting as far as numbers go.  Even hard core statistical analysis is all done by computer programs these days.  I lucked out and just showed up at the same time as cheap calculators too, so all my trig and math stuff back in the day was done on a $30 TI-30 calculator.  Now you can get a good scientific calculator for $10 - and solar powered.  Don't ever end up in a major exam with a dead battery!
Parent - - By welderbrent (*****) Date 02-04-2013 14:33
Diesel (Kara), Good morning.

Kara, don't forget there are hundreds of options available for scholorships.  Rotary Club, Lions Club, Moose, Elk, etc.  These all do scholorships.  Many of them start small similar to one through your local AWS Section.  But then you can advance to other levels (if I remember their systems correctly, I know it advances for AWS).  With AWS you can ALSO get a District and National Scholorship.  They vary depending upon your current grade level and other factors. 

Remember, all of these committees really get excited when they see community projects as well as good grades (not necessarily great grades). 

Most of all, apply for as many as you can find.  Sometimes even when you don't think you qualify.  You would be surprised and the more of them you get the less comes out of pocket.  And I know of no limit to how many organizations can issue you a scholorship. 

Now, not to play on it, especially since you don't seem to be a person that would use it, but you need to see what is available BECAUSE you are disabled.  There are government assistance options there as well.  Also, get an appointment with a college counsellor.  They can really be of help in wading through all the options.

Don't limit yourself Kara, you have a great mind for seeking answers.  You ask the kind of questions that will really benefit not only yourself but the welding community in general.  You make others think outside the box and push us to desiring more answers and practical applications to things we have just taken for granted. 

Think about it hard young lady.  Now is the time to truly plan, set goals, and then push yourself to get there.  You won't be sorry.  But you might be in years to come if you pass it up now.

Have a Great Day,  Brent
Parent - - By deisel (*) Date 02-07-2013 12:00
I'll give it a try, and thanks for all the info.  I don't think I'll be able to go back to school right away though, not til I have money to move.
Parent - - By welderbrent (*****) Date 02-07-2013 14:20
Kara, if nothing else, just think about it, go to wise counsellors (Lawrence, parents, a pastor, who ever you can really trust to be thinking of your benefit), and don't rule it out too quickly.  There are many options out there that get overlooked because we out of hand dismiss it as a wild pipe dream.

Dreams are good.  Then do the research and 'reach for the stars'.  The worst that can happen is you are right back where you started.  BUT, not really, because you gained an experience and may be able to help someone else. 

I hope you stick around this forum Diesel.  You questions are inspiring.

Have a Great Day,  Brent
Parent - By deisel (*) Date 02-08-2013 15:13
Thank you and don't worry I won't be leaving, I have to have some way to ask Larry questions after graduation. :grin:
- - By Dan Stangel Date 02-01-2013 16:44
We have been having some problem with welding OSS using 309/16 weld rod for qualification tests for a bi-metallic qualification of carbon steel and cres, in that after welding and the plates or pipes set for 10 – 15 minutes they start producing an oily/watery like film on them this film is still present the next morning after setting in a warm place over night.  We have changed weld rod manufacture, we have used new cans off the shelf and put new cans in rod holding oven over night, and putting the coupon in a rod oven over night to reduce any moisture that may be in the materials, changed base material and still coming out with the same results.
Parent - - By RonG (****) Date 02-01-2013 18:07
I think I'd put my money on whats in the air not in the material. Metal makes a lousy sponge.
Parent - By ssbn727 (*****) Date 02-01-2013 23:30
:eek::roll::lol::wink::cool:
Parent - By RonG (****) Date 02-01-2013 23:54
Dan, welcome to the greatest welding forum there is. 1st off I did not mean to come across as a smart a$$. My apologies if it did.
Okay,, on to your question. Not trying to talk down to you but you should be aware that PREHEAT is used to slow down the cooling of your weld. In other words, to prevent quenching of your puddle.

Cast Iron is very porous material and could at times be guilty of harboring some moisture but not steel.

The air (Atmosphere) however is (unless you live in Arizona) is froth with moisture and will condense on your work as it cools.
Preheating to remove moisture is over stated and has been kicked around here (on this Forum) many times in the past.
Up Topic Welding Industry / General Welding Discussion / Stump the professor II
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