Page 1 of 2 12 LastLast
Results 1 to 25 of 33

Thread: Craters in tacks (stick)

  1. #1
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Craters in tacks (stick)

    Hi guys,

    I've been flat out on my biggest project yet this week, putting together a saw mill (haven't decided if it will be a swing or band yet...)

    There's not really a weld on it I would complain about yet (other than maybe the one below ), but in the interest of personal improvement I thought I'd ask what I can do about craters forming in tacks. I'm using 4mm rods, 115-130A on 3mm wall RHS, depending on where I'm at. I can do a series of tacks and have most of them make a button I can see myself in but the odd one tears open in the middle. The bead tends to cover them anyway but as I said, personal improvement.

    While I was looking around for photos for this post I noticed I have one at the end of this bead as well... Anything obvious I've done wrong there?

    Cheers in advance of course!
    Josh

    What makes a tack look like this
    Name:  IMG_20190722_173208.jpg
Views: 478
Size:  89.9 KB

    Instead of this...
    Name:  IMG_20190722_173147.jpg
Views: 479
Size:  90.9 KB

    Name:  IMG_20190722_172925.jpg
Views: 480
Size:  126.5 KB
    Name:  IMG_20190721_221357.jpg
Views: 479
Size:  130.5 KB

  2. #2
    Join Date
    Mar 2018
    Location
    Central pa
    Posts
    263
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Millscale !

    Sent from my moto z3 using Tapatalk

  3. #3
    Join Date
    Jul 2018
    Location
    Cumbria, UK
    Posts
    1,046
    Post Thanks / Like

    Re: Craters in tacks (stick)

    it's too small a tack. The metal is rapidly heated up for a few seconds before you break the arc, and the cold surrounding metal sucks the heat straight out of it and solidifies it too fast, causing craters and, if you're too fast, cracking. The second photo looks like a MIG tack.
    I think it's probably also to do with the flux shielding gas not getting established properly with a short tacking time, hence the crap and cracking in the crater.

    The end of the run - are you pausing and back-stepping for a second or so before breaking the arc? If not, try it.

  4. #4
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    It's all stick tacks I don't have a mig machine in my shed =(. Most of them are that size and look ok but the odd one errupts as it cools.

    I do pause and back up I guess I didn't on that bead for some reason.

  5. #5
    Join Date
    Jul 2018
    Location
    Cumbria, UK
    Posts
    1,046
    Post Thanks / Like

    Re: Craters in tacks (stick)

    It's maybe just as Mike says - millscale and oil, sometimes it's bad and sometimes it's not. I'd still be putting a bigger tack in, though. It's maybe just me - I can't do small stick tacks to save my life - if I tried those sizes of tacks it would literally fall apart, lol.

  6. #6
    Join Date
    Mar 2018
    Location
    Central pa
    Posts
    263
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Millscale melts at higher temps than steel you heat everything up and the contaminates melt last boiling up and out if you must weld millscale use a digging rod 6010/11 I always say clean for 30 minutes weld for 3 minutes use a soapstone to mark where to clean so your not doing the whole project

    Sent from my moto z3 using Tapatalk

  7. #7
    Join Date
    Apr 2010
    Posts
    2,809
    Post Thanks / Like

    Re: Craters in tacks (stick)


    JoshNZ


    Quote Originally Posted by JoshNZ View Post
    What makes a tack look like this . . . ?
    Craters [shallows] are normal: both with tacks, and bead terminations -
    and has 'little or nothing' to do with mill scale.

    The better TIG machines actually have a Crater-Fill function. With stick,
    and sometimes MIG, you have to correct/compensate manually.

    This is done by drawing a long arc - thus reducing the heat in the Crater
    and allows the puddle to semi-solidify, then you punch [restore] the rod
    distance to a stable arc.

    Typically, you will 'bounce' the arc several times in quick secession. The
    timing is akin to dribbling a basketball while lowering your hand - this
    increases the rebound frequency of the ball.

    With practice, this will become muscle-memory . . . HTH -


    Opus

  8. #8
    Join Date
    Mar 2005
    Location
    Under a Rock
    Posts
    5,635
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Iím with Munk
    I think the tacks are too small

    But who cares really what they look like...
    as long as they hold. Tacks are tacks.

    Youíre only going to blast over them with a full pen bead anyway...
    so no biggy


    Sent from my iPhone using Tapatalk Pro
    Miller 211
    Hypertherm PM 45
    1961 Lincoln Idealarc 250
    HTP 221


    True Wisdom only comes from Pain.

  9. #9
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Quote Originally Posted by OPUS FERRO View Post

    JoshNZ




    Craters [shallows] are normal: both with tacks, and bead terminations -
    and has 'little or nothing' to do with mill scale.

    The better TIG machines actually have a Crater-Fill function. With stick,
    and sometimes MIG, you have to correct/compensate manually.

    This is done by drawing a long arc - thus reducing the heat in the Crater
    and allows the puddle to semi-solidify, then you punch [restore] the rod
    distance to a stable arc.

    Typically, you will 'bounce' the arc several times in quick secession. The
    timing is akin to dribbling a basketball while lowering your hand - this
    increases the rebound frequency of the ball.

    With practice, this will become muscle-memory . . . HTH -


    Opus
    That sounds good in theory, I will give it a try on some scrap. Does long arcing it not cause it to spatter all over the end of the bead?

    These tacks are for things that are probably going to be moved so I try to keep them as small as possible. And, I really hate when I have done a big tack and it trips my rod up when I'm trying to bead over it, or it's wider than the bead itself and I either have to fatten the bead or leave the side of the tack hanging out. So I've tried to keep them as small as possible lately anyway.

  10. #10
    Join Date
    Dec 2015
    Posts
    524
    Post Thanks / Like

    Re: Craters in tacks (stick)

    If my tacks looked that good, I'd be delighted.

  11. #11
    Join Date
    Mar 2018
    Location
    Central pa
    Posts
    263
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Call me crazy but everyone is saying to small to hot mill scale takes more heat to melt off and allows less metal to deposit so in theory a clean joint will take less heat shorter weld time to tack I've personally only ever had craters on dirty metal besides once tacked it's in place and harder to clean the joint and even though some say just burn through the scale it's a bad idea I can prove it anyone who's ever used a torch to cut clean metal vs dirty or mill scaled will tell you the clean cuts way faster and cleaner with less splatter so I think you are going to hot but it's because of the scale I'm not saying a hot tack won't crater but the scale is causing you to heat that spot more than needed

    Sent from my moto z3 using Tapatalk

  12. #12
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Fair enough Mike. The beads are going down over the scale alright anyway so I'm not too fused if that's the case, I'll just put it down to it being what it is.

    Will have to get the whole thing blasted or galved or whatever I don't know yet. Depends on if it works well or is a flop I guess haha.

  13. #13
    Join Date
    May 2007
    Posts
    3,280
    Post Thanks / Like

    Re: Craters in tacks (stick)

    u can always put a 1/8" wheel on your grinder, and do away w/ the tacks as you go/weld along. but that craters at a welds ends can be inviting future problems. you could have reversed your weld direction . theres a couple manuevers i do to try to fill a crater at welds end, but a lil hard at the workpieces end like that pic , as it gets very hot there anyway

  14. #14
    Join Date
    Apr 2010
    Posts
    2,809
    Post Thanks / Like

    Re: Craters in tacks (stick)


    JoshNZ


    Quote Originally Posted by JoshNZ View Post
    That sounds good in theory, I will give it a try on some scrap. Does
    long arcing it not cause it to spatter all over the end of the bead?
    The technique I described primarily applies to weld-bead terminations.

    The speed 'of the bounce': and the distance when 'plunging to puddle'
    offsets your spatter concerns - typically, several plunges, will be 'half
    a second'
    minus. Albeit, this is an advanced skill . . .

    Weld beads, generally: are run with a full-length rods - and at weld
    bead temperature - tacks, not the case . . .

    Successful tacks: are short, shallow, and strong - and executed to be
    welded over with the least 'after tack' dressing as possible [time is
    money] - and yes, I do opted/need to dress some tacks . . .

    This is what I do -

    I maintain a cache of rod-stubs, of various lengths - two to four inch,
    specifically for tacking. Short rod projections are much easier to site
    and control - and, I tack at a much higher temp. than weld temp. - so
    you can 'wet and plunge' the tack below grade . . .

    This practice usually buries the tack below grade [minimum dressing],
    gives life to rod-stubs, and reduces dressing . . .

    HTH -


    Opus

  15. #15
    Join Date
    Aug 2013
    Location
    Hudsons Hope BC
    Posts
    94
    Post Thanks / Like

    Re: Craters in tacks (stick)

    You are running a 5/32 rod and If you're running 7018 you are a bit light on the amps. Try cranking it up a bit
    Lincoln 350mp
    miller regency
    miller syncro wave 300

  16. #16
    Join Date
    Dec 2018
    Posts
    3,518
    Post Thanks / Like

    Re: Craters in tacks (stick)

    I don't know how you're running 5/32 on 1/8 base metal. I'd be blowing through it in a heartbeat with that big rod I'm usually running 5/32 in the neighborhood of 175amps...…..seems like a lot for 1/8 material.....I sure couldn't do it.

  17. #17
    Join Date
    Sep 2013
    Location
    central Wis.
    Posts
    4,983
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Millscale has nothing to do with it. I've put thousands of tacks on millscale and no issues. Personally I would use 6011 for tacking if I was using stick. To me a crater on a tack is nothing, actually probably preferable as it's less of a deposit to interfere with the actual weld
    Miller xmt304, Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.

  18. #18
    Join Date
    May 2018
    Location
    the Netherlands
    Posts
    237
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Quote Originally Posted by farmersammm View Post
    I don't know how you're running 5/32 on 1/8 base metal. I'd be blowing through it in a heartbeat with that big rod I'm usually running 5/32 in the neighborhood of 175amps...…..seems like a lot for 1/8 material.....I sure couldn't do it.
    ^^^^^^ This.
    I use 2mm(5/64) at 70A or 2.5mm(3/32) at75/80A 7018 on 3mm(1/8) wall material. 1/8 rod is doable but doesn't make live any easier.
    Using 4mm(5/32) rods on that thin material is asking for problems and with 115-130A Your way below of the scope of that rod.

    Edit: What rod are you using and on what polarity? As you are from New Zealand by the looks of your forum name it might be 6013 or 6012 which usualy run on DCEN.
    Running 6013/6012 on DCEN helps a bit to avoid blowthrough, but even then 4mm is still to big a rod for that wall thickness.
    Last edited by E T; 07-23-2019 at 04:14 PM.
    Kemppi minarc 150
    Esab powercut 400

  19. #19
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Quote Originally Posted by E T View Post
    ^^^^^^ This.
    I use 2mm(5/64) at 70A or 2.5mm(3/32) at75/80A 7018 on 3mm(1/8) wall material. 1/8 rod is doable but doesn't make live any easier.
    Using 4mm(5/32) rods on that thin material is asking for problems and with 115-130A Your way below of the scope of that rod.

    Edit: What rod are you using and on what polarity? As you are from New Zealand by the looks of your forum name it might be 6013 or 6012 which usualy run on DCEN.
    Running 6013/6012 on DCEN helps a bit to avoid blowthrough, but even then 4mm is still to big a rod for that wall thickness.
    They're 6013's yeah, smootharc #12s... Or 13s I can't remember, whichever one penetrates through oxides better. I have 3.2mm rods too I sometimes do a stringer at the bottom of a valley but I find capping it with the 4mm at ~130A looks good. Can pull flux off with finger nail and it seems to get decent penetration, I've had to cut a few of them apart I should know!

    Name:  IMG_20190724_114629.jpg
Views: 158
Size:  85.5 KB

    Name:  IMG_20190724_114644.jpg
Views: 160
Size:  91.7 KB

    Name:  IMG_20190724_114657.jpg
Views: 159
Size:  83.9 KB

  20. #20
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Was just looking at the box for what it's worth they do say 120-195A

    Name:  IMG_20190724_125834.jpg
Views: 154
Size:  63.7 KB

  21. #21
    Join Date
    Dec 2018
    Posts
    3,518
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Quote Originally Posted by E T View Post
    ^^^^^^ This.
    I use 2mm(5/64) at 70A or 2.5mm(3/32) at75/80A 7018 on 3mm(1/8) wall material. 1/8 rod is doable but doesn't make live any easier.
    Using 4mm(5/32) rods on that thin material is asking for problems and with 115-130A Your way below of the scope of that rod.

    Edit: What rod are you using and on what polarity? As you are from New Zealand by the looks of your forum name it might be 6013 or 6012 which usualy run on DCEN.
    Running 6013/6012 on DCEN helps a bit to avoid blowthrough, but even then 4mm is still to big a rod for that wall thickness.
    Years ago, I ran 6013 on AC current. AC was all I had back then. I believe 1/8 ran good at around 125ish amps.

    Only rod I weld with, is 7018 these days. Usually DC, but sometimes AC (made for AC rods).

    I don't believe I've run more than a coupla pounds of 6010/6011 in all my years. I just don't use it, never did.

    And I'm not from New Zealand (although I'd sure like to see it one day), I'm from Oklahoma. I'm pretty sure Oklahoma isn't high on anybody's bucket list

  22. #22
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    I'm biased but I do think NZ is neat. Can be frustrating at times. I used to see things on eBay and Craigslist for a tenth the price of what you can get something here in NZ. Uncommon items...

    I do have a box of 7018s there too. I ran a couple and didn't much like them they're quite different to the 6013s. Plus I don't have a rod oven =/. They're stored in a heated office so not wet but...

    Does it matter for these backyard hack jobs? I really hated how the end of the rod closes over for relights

  23. #23
    Join Date
    Apr 2019
    Posts
    22
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Opus I've been getting some nice finishes playing around with your bouncing technique. By the way I interpreted your bouncing ball analogy I thought the first 'bounce' would be the highest but after thinking about it, I assume your first long arc is the shortest and progressively bounce higher as to cool the puddle?

    Starting high and then bouncing lower would cool it a lot at first then begin heating it more again, in my mind.

    Have been running multiple fillets trying to get the legs to pull out straight around their braces. Had a heck of a time keeping that thing square.

    Would almost be nice to put a button on the stinger and use it in Tig mode to make use of the taper off function

    Name:  IMG_20190724_155732.jpg
Views: 121
Size:  85.4 KB

    Name:  IMG_20190724_145417.jpg
Views: 122
Size:  60.5 KB

  24. #24
    Join Date
    Jun 2012
    Location
    Laredo, Tx
    Posts
    5,173
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Quote Originally Posted by Dee_veloper View Post
    If my tacks looked that good, I'd be delighted.
    Right? That one tack looks like it could have been done with TIG!
    1st on WeldingWeb to have a scrolling sig!

    HTP Invertig 400
    HTP Invertig 221
    HTP ProPulse 300
    HTP ProPulse 200 x2
    HTP ProPulse 220MTS
    HTP Inverarc 200TLP
    HTP Microcut 875SC

  25. #25
    Join Date
    Jun 2012
    Location
    Laredo, Tx
    Posts
    5,173
    Post Thanks / Like

    Re: Craters in tacks (stick)

    Quote Originally Posted by OPUS FERRO View Post
    The better TIG machines actually have a Crater-Fill function. With stick,
    and sometimes MIG, you have to correct/compensate manually.
    Well in TIG, the crater-fill is done with the pedal anyways, unless TIG is the secondary feature in which case the slope-down helps with this. Crater-fill I have mostly seen in reference to newer inverter migs that have a slope-down function that works in conjunction with synergic heat-control, which in essence is a crater-filling function.

    HTP stick welders can also have a crater-fill function by using the remote slider control. No need to work the stinger manually, just slide the current down a little bit at the termination, and it fills the crater nicely. I don't even have to whip-out, just drop the slider all the way down fast, and it practically extinguishes the arc when it goes down to 4A. I have a good 3ft of slack so I can remove the slider from the stinger and hold it with my other hand as well.

    Last edited by Oscar; 07-24-2019 at 11:35 AM.
    1st on WeldingWeb to have a scrolling sig!

    HTP Invertig 400
    HTP Invertig 221
    HTP ProPulse 300
    HTP ProPulse 200 x2
    HTP ProPulse 220MTS
    HTP Inverarc 200TLP
    HTP Microcut 875SC

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Page generated in 1,607,103,577.88437 seconds with 12 queries