Welding Tips and Tricks

2" sch 160 SS. Scratch start, air cooled, no pedal. X-RAY. Trying to avoid fisheye on the last tie in on the last pass of my cap. Tapering away slowly seems to help but its now very visually pleasing and sometimes still craters a little when I snap out. If I taper slow and roll my tungsten way up without snapping then I got arc going all over the damn place making a mess. if I taper away too fast it still seems to crater but no as bad. is it possible that the test supervisor will expect that given the circumstances?
Experimenting with tapering out of the cap and onto the pipe, however I don't know if that is allowed or if it would be considered arc strike. Any insight will be appreciated. I have a lot of time and money invested in practicing for this test and would hate to get past the root and screw up the cap! watched a video with jody and his copper welding spoon on plate. thinking about taping a piece of copper at my tie in termination point to roll my arc onto. ever herd of anything like that? theyd probably run me off!

Hi, welcome to the forum.
First of all don't run off onto the pipe, it will definitely be considered stray arc strike and fail visual.
It's ok to have a fish eye as long as the crater has no depth to it. Often you finish and what you think is a fish eye is actually standing a little proud. As you run your cap over the the top of the cap start there is quite a depth of unmelted solid passes underneath so there is unlikely to be crater cracking due to shrinkage.
You might try to keep moving as you roll out.
You have concerns, post up a pic so we can look at it.
Cheers,
Vic.

Coldman is right. Arc marks of any kind are supposed to be a look out on test day. Keep practicing the taper off of ark length. As long as it's not below flush you will be fine.

thanks for the insight. very helpful.

Coldman wrote:Hi, welcome to the forum.
First of all don't run off onto the pipe, it will definitely be considered stray arc strike and fail visual.
It's ok to have a fish eye as long as the crater has no depth to it. Often you finish and what you think is a fish eye is actually standing a little proud. As you run your cap over the the top of the cap start there is quite a depth of unmelted solid passes underneath so there is unlikely to be crater cracking due to shrinkage.
You might try to keep moving as you roll out.
You have concerns, post up a pic so we can look at it.
Cheers,
Vic.

Vic sez: "It's ok to have a fish eye as long as the crater has no depth to it.
Often you finish and what you think is a fish eye is actually standing a little proud.
As you run your cap over the the top of the cap start there is quite a depth of unmelted solid passes underneath
so there is unlikely to be crater cracking due to shrinkage".

Craters always have some depth, usually to the bottom of the puddle it was formed in
Craters always show as NDT indications and immediate rejection, just on visual b4 NDT
Craters exhibit tiny, tight cracking on the periphery.

Vic, educate the rest of us, please--what applicable spec's./codes are you referring to
for the acceptance of craters?

Dave,

A "crater with no depth to it" is not a crater. Vic is using the OP's terminology to describe for him the teat one often gets on a good termination, that can be knocked off with one quick file stroke.

Steve S

If the op cares to post up a pic we can solve this one pretty quick. Steve is right about my interpretation.

OP?

never mind. original poster. I see. lemme see if I can get some pics on my next cap. they are improving.

Thanks Red, looking forward to seeing them.

Finally some picks for you guys. Most of the pics are free hand passes. Been experimenting with walking the cup and i find the roll out is giving me better results. I actually had 1 or 2 terminations that produced the "teat" that was actually "standing a lil proud" and now know what you mean by a good termination. Had a couple of good freehand terminations also. just not consistent yet. More prayer and practice.

How many amps? What size filler? I like 3/32 or 1/8 rod and about 130-150 amps for test day.

Running around 100 to 115 after I get some meat on top of the root. using 1/8 filler because its sch160 so theres a lot of bevel to fill. switching to 3/32 when I need to run stirpers or flush out shallow spots before capping. I'll crank up.

Try bumping up your heat some. Do it about 5 or ten volts at a time. If you slowly increase the amps by 5 or 10 then run several whole welds you will slowly get used to it. Running that cold after the hot pass can make you go too slow which will put excessive heat into a test piece like your using. That can cause the greying. Watch the interpass temp. I like 3/32 for my root and hot pas then switch to 1/8 for most of the fill till its flush. Then I watch the interpass temp very close on the cover. I back down my amps down a bit and switch back to 3/32. Lots of pipe tests specify not rolling or moving the pipe position durring the test. are you practicing for a 6G position weld?

Oh yeah, it stays in position. Will be mindful of interpass temp