CV or CC for solid wire

Date 07-09-2012 00:52

The LN-25 is a Voltage Sensing Feeder. That basically means that the Feeder is "Stupid" and has no idea whether you are running CC or CV. It will seek the Voltage needed and correct itself for the application. I know you will get different opinions on this. The "Proof is in the Pudding". Run it on a SA-200 without a Module. It will run just fine.

By Tommyjoking (****)

Date 07-09-2012 03:10 Edited 07-09-2012 03:19

I have wondered how straight wire (er70XX) with gas would run on CC myself. On ornamental or handrail type stuff weld integrity would not be a big issue....how it lays down would. As far as buckshot and how controllable it is with thin to thick or thinner sections of metal is the real issue not necessarily a code compliant weld. I have been told it will weld ok but I have not had the chance to try it out. Straight out of the gate that Ln-25 will run either innershield or dual shield.....why go to the expense of dual shield when it is all about deposit speed...you will still have the same clean up issues and welding position/direction of travel issues. Anyone use a suitcase with straight wire and 75/25 regular?

By ccpi Date 07-09-2012 04:02

You should be able to run anything that has a spray type transfer. CC power sources don't like short circuit mig.

By weldwade (***)

Date 07-09-2012 06:06

I have seen the results of solid wire run on CC. Lots of buckshot and not as controlable. Yes it can be done. I would not use it because it would add extra hassle and clean up to the job. You will have better results with CV.

By 357max

Date 07-12-2012 21:49

Does the Big 40 CC have an arc control or dig control? If it does; you might get short circuit with the LN25 by setting the 40 at maximum current with the dig control (which is basically a cv "foot" on a cc volt amp curve) at maximum. Adjust the ln25 to get short circuit voltage 16 to 20 volts. To decrease volts increase wire feed speed. Conversely; To increase voltage decrease wire feed speed.
It takes about 350 amps to clear the short circuit with 035 ER 70S wire. Dependent on Wire Feed Speed the number of short circuits will determine the welding amperage because of the cv foot.

By Iron Head 49 (***)

Date 07-20-2012 10:22

Here is some Lincoln L-56 ran with a Red Face, and LN-25 on CC.

By crahner (**)

Date 07-23-2012 04:15

A picture is worth a thousand words. I hear what everyone has been saying and now there is no arguing it. It appears my days of flux core may be fewer and fewer.

Thanks to all who provided information.

Casey

By 357max

Date 07-23-2012 21:59

thanks for the foto; it shows that you have set the machine for maximum amperage at minimum voltage ie near a constant voltage volt amp curve. basically setting slope control. how was the "operating window" for adjustment? thankyou for sharing

By Iron Head 49 (***)

Date 07-24-2012 09:14

357max I have a Cable remote on the machine. Only differences I found, seems as I had to run a little hotter than with a CV machine, but with Mig that is always a good thing! There seems to be a smaller window for the sweet spot with stick out. Just a little bit more splatter too, this was with C-25. Other wise no big deal.

By Cactusthewelder (*****)

Date 07-09-2012 03:44

Large Steel Erection Companies like American Bridge and Peterson Beckner and CBI have been running Innershield with LN-25's for 30 years and they all test just fine. Most ofthe Machine they used in the early days were SA-200's. Like I said, the LN-25 is Voltage Sensing. No CV unit is needed

By Sberry

Date 07-17-2012 21:40

I have worked for both AB, a couple times as well as CBI but never used engine drives with them, AB had truckloads of 6 and 8 packs, 600A CV machines, its been some time ago, LN23's I believe?? 202 and 203 innershield. If anyone has been in Miami you can see the space frame on the now Wachovia bank, I was on that, welded connections to the building and splices joining the sections together. A guy named Dave Black was from AWS was down there on occasion, this was when innershield was really making inroads in the erection biz. All full pen, back gouge stuff. Was a strange deal, fabricator really had the bevels on wrong side of one side only.

By Lawrence (*****)

Date 07-09-2012 05:37

If the requirement is to work good and last a long time you are prolly ok.

But I want to clear something up.

As far as "To Code" goes..

D1.1 does *not* distinguish between Self shielded (innershield) or Dual Shield FCAW... Or GMAW spray transfer for that matter.... If the power supply is CC the WPS must be qualified by testing via clause 4 in order to be compliant with code... No exceptions.

See AWS D1.1 3.2.4

By crahner (**)

Date 07-11-2012 01:43

Thanks for all the replies. I believe I will continue to run innershield with little more clean up until I have a CV machine.

Thanks,
Casey

By Cumminsguy71 (*****)

Date 07-12-2012 21:58

I've got an LN-25 but typically use it with my ranger cv. If you have a decorative job and your considering using an innershield or flux core you've go a lot more time on your hands than most. I did one rail out of desperation(ran out of 75/25) and swore I'd never do that again. Makes a bloomin' mess everywhere, smoke, spatter and all has to be cleaned off. If you have a LN-25 set up to run solid wire and gas I'd try it out cc and see see what happens. I'd rather eat a plate full of dog doo then ever use flux or innershield on anything decorative myself.

There have been tons of post on here over the debate of whether you can use cc with these. Mine has a switch inside so you can tell it, cc or cv. I've even talked to people from Esab and Lincoln asking and nobody can give a straight yes or no answer.

By crahner (**)

Date 07-14-2012 23:49

I agree it does make a mess. So far it has been how I have helped our local economy, keeping a grinder in a kids hand.
I have never been able to get a straight answer either so I guess I will keep using what I know. Sometimes you cant teach an old shade tree new tricks I guess.

Thanks

By Cactusthewelder (*****)

Date 07-15-2012 00:24

Once again. The LN-25 is a VOLTAGE SENSING Feeder. It is "Stupid" It does not know if you have CV or CC. It Senses the Voltage it needs. When set right, it will run ANY wire as effecient as ANY other machine. Sometimes the problem lays between the Shoulder and the Holder. Not the Feeder or Machine. Get a Filler metal manual from whatever brand of wire you are running. Set the suggested parameters then tweek it to your personal taste. That is as straight of any answer as I can possible give you. Other than that, I can give you the cell phone number to Mr. Bob Lynch. He is the Filler Metal Specialist for Lincoln and Esab. He can give you ANY answer you want concerning HOW to run any specific wire. If you happen to be close to Houston, he will show you.

By Paladin (***)

Date 07-15-2012 02:03

Cactus is right. I normally run my Miller VS Suitcase with my Miller Pipe Pro. It has a setting for VS feeders. I have self shielding flux core on it now and after reading this post hooked it up to my old SA 200 to see what it would do. It took just a bit of fiddling with to find the setting but it ran the wire fine. Set you wire speed where you want it then find the current setting that works.
Floyd

By 803056

Date 07-20-2012 15:08

If my recollection is right, you set the switch to the type of machine you are using to power the wire feeder, i.e., set it to CC if you are using a constant current power supply or CV if you are using a constant voltage (potential).

As noted, if you are working in accordance with the 2006 or later edition of D1.1, the power supply must be constant voltage if the contractor (welder) does not want to qualify the WPS per clause 4.

It is no longer relevant what was done in the past, if the Engineer, Owner, or building code stipulates D1.1:2006 (or later), the new requirements are mandatory. A prequalified WPS must specify a constant voltage power supply when GMAW or FCAW is to be used. The following is the clause taken from D1.1:2008:

3.2.4 FCAW and GMAW Power Sources. FCAW
and GMAW that is done with prequalified WPSs shall
be performed using constant voltage (CV) power
supplies.

Best regards - Al