flux cored wire welders

[golfpin]

morning all,
comments please, here in South Africa the powers that be , in this case the Motor Sport Ruling body, have for what ever reason decided to ban brazing in any form on a race car! This is to me moronic. Where or why this has come from is beyond me.
I spent nearly 10 years of my life in the UK building race cars using what the Brits refer to as Nickel
Bronze welding, which to all intents is very similar to brazing depending on the filler rod. My question now is can anybody advise me as to the strength of a wire feeder weld of the cored flux type. I have used the C02 type and every other type.
My concern is that a car that I designed and 3/4 built sold, and have now been commissioned to finish it. The welders concerned are the horrible Chinese type and I have not found anyone who has used these or a source as what could be considered good wire or a reasonable machine. Experiences thoughts would be appreciated.
Golfpin

[redneckalbertan]

Not the advice that you are looking, but as opposed to wire welding what about TIG welding. If you have the hand skills to braze or oxy fuel weld these are very similar to TIG welding. TIG provides a far superior weld compared to the other common hand welding processes. You can run a TIG torch off of any stick welder. Steel is normally TIG welded with a DC straight polarity. All you have to add to your stick welder is a TIG torch with a gas valve. Another thing to note is you need to derate the duty cycle of the given machine, I have heard some say this needs to be done on both AC process and DC process and others say on AC process. I can't remember how much it needs to be derated by and a quick Google search didn't turn anything up for me today. (No need to derate duty cycle on dedicated factory intended TIG machines.)

Here is apocture of a TIG torch with gas valve.

[redneckalbertan]

As to answer your question. What are you looking for, gassless wire, or a gas shielded flux core wire? As for the wire, and considering race car building, it all depends on what alloy you are welding. At time some fairly exotic alloys are used to increase strength and decrease weight in the chassis.

As a generality choose a name brand. Big names stand behind their product and have a reputation to defend and are less likely to continuously produce a lousy machine. I am a Miller fan, know and like their machines and steer people towards them. Lincoln makes good machines, I just don't like them. I have not used ESAB machines much, but the little I have used them I have liked them, I love my ESAB plasma cutter and recomend them above other plasma cutters.

If you are looking at a gas shielded flux core wire I am unsure how large of a machine to recomend. I normally use hard wire until I get into heavier weldments, so naturally require a higher amperage and larger machines. Figure out the wire you want to use, thickness of wire, and the thickness of the material to be welded and the salesman should be able to tell you the amperage needed for the weld and the size of machine needed. Bigger is almost always better.

[steamin10]

I have 2 Lincoln red box machines, low end, and they are futsy at best. I keep the Larger one for aluminum, to avoid steel contamination of the feed tubing. I use my big Robot 400 amp machine for touch lift TIG. It needs a freq box to do well on stainless or aluminum.

In my honest opinion, light weight tubing and race cars stress, just scream TIG to me. All the picky little problems I have with the carry around machines, tell me a machine of several orders higher on the food chain, might get close to something I would work with on this type of project. Better arc control, power, and duty cycle would be my arguments, moving toward a premium product.

Probably not what you want to hear. Tubing welds are in class of difficult all their own. A local builder of chassis used a rotiseri to do the final welding after fitout, just to get the best position for flat welding with wire. He is out of business, because a racing team failed to pay for the last 2 chassis.

[golfpin]

To all that replied, a big thank you,
Sadly I sold my Tig set up a few months back, before the order to complete said race car came in! So when I started to sniff around I found the little [size] inverter type welders also could do Tig but when I did the finances the cost of the Tig torch etc here was nearly half of the welder but the killer was the rental demanded by The Afrox giant for the bottle ... hence my query re fluxcored wire and the strength and so on. One of the reservations I had re the wire is that I had noticed that it was difficult to get as neat as weld/bead as one can with nickel bronze this is further aggravated by the the thin wall mild steel tubing I am using mostly, 18 swg and 20 swg [1.2 mm and .9 mm] If I can get around the idiots who have banned high tensile low temp [brazing/bronze/nickel] made famous by Eutectic 16 and Allstate, amongst many others , that would be the way to go.
What is equally anonamalous is that all Brit built Race car chassis [spaceframe type] from about 1948 to about 1973 are Bronze welded and thousands are still running world wide so why the ban?
Would be interesting to know what the various racing motor racing bodies in the US have to say about this,
With thanks to all,
Golfpin

[Carm]

I cannot help with the brazing/welding controversy for race frames, as I know nothing about the sport.
I am very familiar with pressure piping and structural piping (offshore rigs), so can venture a SWAG or two. (sophisticated wild ass guess)
Brazing by its nature can never match or exceed steel's yield or tensile. I am familiar with brazed joints on motorcycles that are entirely sufficient for service conditions, and silver brazed socket joints on fluid/gas instrumentation lines that would belie that statement.
Personal/public safety seems the primary driver for regulation. Welding chrome moly is an involved process with strict protocol in piping. Probably has similar requirements in racing, but likely not adhered to due to cost involved. Most reasonably competent workmen can weld mild steel and meet conditions of acceptability without further expense or third party assessment.

Since you are limited to an electric welding method by economy it would seem your best choice would be a simple transformer welder using stick electrode. Certainly a proven process, very versatile and not needing the purchase of filler metal beyond your needs- any spool welder requires a minimum purchase. If I needed two pounds of 310SS, 30+ pounds would sit on the shelf with poor resale value. One superlative advantage of stick is the low weight and ability to reach into tight spots...the smallest wire gun is considerably heavier/larger and has strictly limited stick-out.

If fluxcore it must be, the primary concern to my mind would be quality of consumable manufacture. Provided the power source and feeder were consistent, the learning curve would have less arc (haha) than the stick method.

[golfpin]

Thanks again to all for the input,
I am a little confused, Redneckalbertan you referred to gasless wire and then to gas shielded fluxcore wire to me that is a bit of a contradiction in my definition and terminology. Forgive my ignorance but as I understood there are 2 forms of wire weld systems one uses, eg CO2 as a flux shield and the other type where the flux is in the core of the wire and then no Co2 bottle the rental of the bottle is the killer, is there another system that I am not aware of. While surfing the web I have also found out that disposable Co2 bottles are available in Australia!
Thanks, all info is pertinent and valuable,
Golfpin

[warmstrong1955]

There are many kinds of wire.
Gas, Dual Shield, and Self Shielded.

Wires I use:
Lincoln L56, which is solid wire, requires gas.
Lincoln 71, which is a dual shield wire (they call it 'Outershield'). Has a flux core, but still requires gas.
I have a roll of flux core, self shielded wire,Corex 11GS.

I've used the Corex a couple times....when the wind was blowing and I was welding outside.
I don't care for the stuff. Not an exceptionally good looking bead, so I generally go old school and stick weld outdoors instead.
May be me....may be the wire. It was something the local Welding supplier had on hand, and I thought I would try some. I don't have a lot of experience with self shielded wires, so I can't be much help.

Bill

[BadDog]

Like you, I could never get happy with self shielded wire (common flux core). Once my buggy no longer fit easily within my shop (due to tires and new machines) I tried it for welding outside. Maybe I didn't spend enough time with it to get the skills, but I really didn't like it. Not only ugly, but harder to prep for paint and lots of inclusions, and not something I trusted on my roll cage/body (or suspension, etc). I wound up buying one of those big tent garage things so I could eliminate the inevitably unfortunately timed breezes (of gusts!). Round tube joints present enough issues with constantly varying angle and positional changes, plus acute angle interference often resulting in excessive stick-out.

But I never had the skills with stick either. I could do the easy stuff as long as the material was 1/8" or better with a good DC power supply and the right rod. But get me out of position, or with some of the less friendly rods, and I was in trouble. My family was chock full of Boilermakers and Nuclear rated Pipe fitters, and it was strictly embarrassing to be welding along side them. They tried, but I just never spent the time to learn properly, and I regret that now, I wasted SUCH a great opportunity there. I recently added TIG back to my collection with a Syncro 351, and I'm enjoying it.

[redneckalbertan]

Redneckalbertan you referred to gasless wire and then to gas shielded fluxcore wire to me that is a bit of a contradiction in my definition and terminology.

Bill summed it up well in his reply, I will add that the flux in a flux core wire that requires gas shielding is used for adding alloying elements to the weld. Why it is done that way as opposed to making a solid wire of the correct alloy I don't know.

One thing that you may want to consider, maybe you have already (I don't know), can you purchase a bottle from Afrox instead of renting it?

For TIG welding mild steel you would use Argon shielding gas, I would assume the same for a chrome molly, but I am not sure. I don't know if you could get disposable bottles of Argon.

For self shielding wire I have used 2 different wires one a name brand the other a cheep import. Stick with the name brands. They were night and day difference between the two wires.

[golfpin]

Hi Red thks for the reply, unfortunately Afrox will not sell gas bottles only the tiny porta pack that now sell for ........... best price R15000 divide by 12 to get a plus minus $ figure. That is the killer and one of the reasons I have steered clear of them as much as poss. The cost of filling what I refer to as the large bottles no small bottles available anymore from many years back, is now just shy of R 2000 here gas it is sold by weight both OX and acy and all the other gasses, and these are only available on a rental basis.
Just to clarify this whole thread, regulating body MSA [Motor Sport SA] have banned the use of brass in any form on race cars. The car I have been building for thr last 15 years I have sold, it is nickel bronze welded. The now owner of the car has asked me to finish the car hence my ? about MIG etc in all its forms
Any chance you might know of the strength of a co2 weld pref in PSI [I am old !!!|? Disposable Argon no!!
Many thanks or your input

[warmstrong1955]

Just a suggestion....

If you want to avoid buying any gases....skip the MIG, and just go old school....as in stick welding. Get a good DC welder. AC's are OK for fixin' lawn tractors and such..... just my opinion.....

First dune buggy I built, was .095" wall 1-1/2" tubing. It was a precut & preformed kit. I welded it up with 3/32" 5P (6010). Back in the day.... most guys welded their buggy frames with stick. MIG's were for the 'rich folks'.


Gather up some scrap tubing, and play around, and learn. When you get a handle on it....weld the real deal.

6010, is 60,000 PSI. With decent welding skills, the welds are stronger than the tubing. Trust me.... I've seen lots of buggies rolled on the rocks & dunes....and the highway, and the welds are not what fails or bends.

I've welded some frames with 7018 too, but you should master the mild steel rod first....and learn how to tell flux from metal in the puddle (that's the secret) ....and then you can try some lo-hy.

Bill