Announcement

Collapse
No announcement yet.

GMAW-Silicon Bronze Wire

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Noel
    replied
    The plan was to check before putting the cover back on, really, but I didn't... So much for that good intention?

    When I took welding In high school I had a buddy who took auto mechanics. He used to say he'd never be out of work because nothing lasts for ever, and even if designed to last forever, people will fail to maintain the condition for it to do so.

    I'm sure a new doodad may have bumped upped a signal, like a new cam shaft in a car, but If the wheel bearing are dry seized from lack of grease, you ain't going places unless you really rev'er up good?

    Food for thought? From reading numerous posts, the talk of a cause is plugged or kinked cable? Hmm? Is it really?

    Leave a comment:


  • MasterKwan
    replied
    You know, as a old army tech and programmer, I've found sometimes things just want to come apart and be put back together. Then they start working. Usually it's a sign of something intermittent like maybe a broken wire under the insulation. If it happens again, I'd go first to measuring voltage at the motor and the 24v ac input. For most electronics, power in is the first thing that needs checking.

    Leave a comment:


  • Noel
    replied
    I had, and it seems the pot is functioning correctly. Presently it's going back together. With the assumption ( not that I know anything much about this stuff?) was that low voltage couldn't over come resistance to power the motor, I disassembled the unit to free it up with a good cleaning and relubrication. If that doesn't do it, well, out comes the board and I'll be replacing a power transistor?
    Connected to 12 volts the motor spins like a blender. Connected and checked in the welder we should know soon enough?
    Thanks for the advice, I'll up date soon the results.

    EDIT: It works. Low wire speed and I can't stop it from turning with my fingers. I don't expect drive roll pressure will change that? But No board parts were changed. The grease was GM chassis, and although I haven't ran wire, I'm going to say, problem solved.

    Not that it accounts for much in diagnosing this problem, but when the power windows in my old Van weren't going up or down very quickly, I was the guy who took apart and greased them to work again? Who knows, it could be something to consider?

    MasterKwan, thanks for stepping in with your suggestion, it's appreciated.
    Last edited by Noel; 01-16-2019, 06:47 PM.

    Leave a comment:


  • MasterKwan
    replied
    When the WFS "pot" was set low in range, 3-4 on the dial, finger pressure holding the drive roll would keep the drive roll from turning, or clamping pressure would prevent it from turning.
    https://www.hobartwelders.com/files/.../O944C_HOB.pdf

    Assuming this is the manual, the pot goes to the motor control board which takes 24v ac off a transformer. Then you get a DC output to the feed motor. I'd probably check voltage to the feed motor itself. Looking at meter pics and it seems to be set for testing diodes. I'd probably switch it over to a real resistance range and try again.

    Leave a comment:


  • Noel
    replied
    Gas Metal Arc Welding is a very broad title.
    Metal Active Gas. Metal Inert Gas. Not so much?
    Brazing...

    BRAZING (B) IS a group of welding processes in which the joint is heated to a suitable temperature in the presence of a filler metal having a liquidus above 840'F (450'C) and below the solidus of the base metal. The filler metal is distributed between the closely fitted faying surfaces of the joint by capillary action. Braze welding is differentiated from brazing because the filler metal is deposited in a groove or fillet exactly at the point where it is to be used and capillary action is not a factor. Brazing is arbitrarily distinguished from soldering by the filler metal melting temperature. In soldering, filler metals melt below 840'F (450'C). (Credit AWS)

    GAS METAL ARC welding (GMAW) and flux cored arc welding (FCAW) are two distinct processes, but they have many similarities in application and equipment. Both processes use a continuous solid wire or tubular electrode to provide filler metal, and both use gas to shield the arc and weld metal. In GMAW, the electrode is solid, and all of the shielding gas is supplied by an external source.
    (Credit AWS)

    With torch brazing, using a flux coated copper zinc rod, or even in the case of bare silicon bronze rod, oxide removal is key to good bonding. The strength of the bond.
    With the electric arc of GMAW, under the blanket of shielding gas, electron travel actually results in surface melting, busting up, breaking up, burning up of surface oxides. And yes, with GTAW as well a similar effect occurs. Ok...and with torch brazing if you heat it excessively.

    To date I've read about 160 posts on WFS problems...I've been copy and pasting them onto a sticky note on my desk top. What I haven't found was the relationship between the pot, the lack of drive motor torque at low pot (WFS) settings, why it over comes the low torque at high pot (WFS) settings, or the explanation to explain it.

    I did however find lots that said to say change the board, or the problem is the board. Something on the board for the adventurous to change after testing this or that. I haven't yet.
    But I'm going to eventually.






    Leave a comment:


  • MAC702
    replied
    Originally posted by aametalmaster View Post
    I always called it MIG brazing since it doesn't melt the parent metal. Bob
    When I first started reading about it, I was VERY confused until I learned this by reading between the lines. It's been given a great misnomer. I'm with you in using the correct term of brazing.

    Leave a comment:


  • aametalmaster
    replied
    I always called it MIG brazing since it doesn't melt the parent metal. Bob

    Leave a comment:


  • Noel
    replied
    Originally posted by MasterKwan View Post

    I just used a relatively normal WFS, sounds almost like your wire was slipping on the drive wheels or getting hung up in the gun.

    Wasn't slipping, the drive rolls weren't turning. The question is why?

    When the WFS "pot" was set low in range, 3-4 on the dial, finger pressure holding the drive roll would keep the drive roll from turning, or clamping pressure would prevent it from turning.

    The pot rotation is 0 to 100. Clamping a meter to it, it's range shows a gradual increase. As shown thru it's range of motion, again around 8 on the dial it goes open. Around 5-6 it would actually start over coming the finger or a clamping pressure and spin the motor to once again feed the wire.

    With out any finger or clamping the motor would increase or decrease speed of rotation as the dial is turned.

    If you look at the pictures, you will see increments increase from zero to 100. As mentioned, the little white mark changes and around 7-8 it goes open. It does appear to function?

    Doing some reading of past posts and trying to make sense of it, I'm not clear how it all works and functions? By all accounts things work, just not working well?

    While I don't have a problem with just accepting something for face value, a better understanding is what I'd like to identify why the problem exists, how it's caused in occurrence?

    Any explanation will be appreciated.

    Leave a comment:


  • ryanjones2150
    replied
    This stuff ain't cheap either.

    Leave a comment:


  • MasterKwan
    replied
    Ryan...remember this is a filler that melts and fuses through mechanical metallurgical adhesion.
    I liken it to "metal glue" since the base metal doesn't melt. So yes a gap to let it flow to both sides is a good idea. I used .023 too.

    Leave a comment:


  • ryanjones2150
    replied
    The wire I got is .023. I got it to work out a welding plan for a friend who is restoring an old fire truck that needs some body panels repaired. Been kind of waiting on him to get it ready for me. Maybe I'll poke that bear and see what happens.

    Leave a comment:


  • aametalmaster
    replied
    There is a big write up at mig welding uk https://www.mig-welding.co.uk/brazing.htm that has been around for 10 years or more. I did quite a bit of it 9 or 10 years ago welding auto panels and .023 Crown Alloys wire. It worked so good if there was a small gap between the panels. Now I have 2 giant spools and no welder...Bob

    Leave a comment:


  • Noel
    replied
    2019...While scratching this off my list I discovered an equipment problem. I'm working to understand it. Shortly after that I hope to solve it. But this Argon mixed gas thing. This is the result of mixed gas. 75/25.

    Hopefully, if a person looks close enough they will see subtle differences, that when given to thought, bring to the conclusion and say, yes, I can see how the shielding gas could cause that to occur?

    All these pictures were taken in the last few days to a week. While admittedly, those recently taken before I disabled the Hobart with the mixed gas are presentable, Argon is however recommended for a reason. When I get the issues with my WFS and lack of motor drive torque solved, I expect better results.

    Using mixed gas...the big difference I noticed was the crispness. It short circuits are snappy. Argon has less snap and more splat. I was however limited in my WFS adjustment range due to equipment issues? While the change was as simple as a shielding gas change over, adjustment to voltage, WFS, stick out and travel speed will yield different results to the welds appearance.

    Ryan...remember this is a filler that melts and fuses through mechanical metallurgical adhesion. Remember the shielding gas? Argon is recommended because it's lower ionization potential means it's going to make the puddle hotter and more liquid, or rather has the ability to do that. The gap, is to allow the liquid to flow thru, and wrap the bottom edges. Rounding away the sharp edge top and bottom aids that effect. The gap, will depend on your other parameters, and how you choose to weld the product.





    Leave a comment:


  • MasterKwan
    replied
    I always leave a gap when doing thin sheet metal. Normally about the thickness of the wire. I'm far from an expert though. One nice thing about this stuff is that it cleans up really easily with a roloc disk.

    Leave a comment:


  • ryanjones2150
    replied
    C25 is better eh? I'm glad you said that. I got a couple pounds to try in the small mig machine and was planning to run straight argon.

    As I understand it's mig-brazing. When you fixed your hood, did you leave a gap? Supposed to be able to braze the joint from both sides in one pass. That's how it's been described to me at least. So I'm interested in it for thin sheet metal like auto body panels. Not that I do it for money, but for my own junk.

    Leave a comment:

Working...
X