Help with my 7018 fill and cap. Porosity

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My test.2"schedule-160root/hotpass-6010 5p+fill/cap- 3/32 7018 (oven stored)on a 45deg.I get porosity every once in a while. Gets me pretty frustrated because all looks good until I grind to see if I have porosity and I will find a dot or three. Sometimes even on my stops on the surface. But 90% is in my starts.I try to keep the arc short but my hands pretty shaky. I run at about 95 amps. Just wondering if anyone has any tips on how to spot it happening so I can correct it and avoid making the same mistake.thanks
Reply:Porosity at the start of a 7018 weld is always caused by too long of an arc which translates to lack of shielding.Shorten your arc while starting or start the arc closer to where you want to start laying down metal. Be consistant and start all new rods the same way, with short arcs.Last edited by snoeproe; 06-19-2012 at 10:16 PM.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:what brand 7018's?do you know for a fact they have always been stored in a heated oven since being opened?windy conditions?any pics?
Reply:something else,95 amps sounds fine but with differences in machines and such its hard to say on the net but 7018's like to be ran on the hot side.  I like for the rod stubs to be glowing dull red when i'm done.and,try starting 1 inch or so ahead of your tie in and dragging it back to the start, that helps get any sputtering over with before you start actually laying down weld metal. You got to do that in the bevel and weld back over the pecker tracks.hope that helps
Reply:Originally Posted by snoeproePorosity at the start of a 7018 weld is always caused by too long of an arc which translates to lack of shielding.Shorten your arc while starting or start the arc closer to where you want to start laying down metal. Be consistant and start all new rods the same way, with short arcs.
Reply:Shorten the bite on the rod or goose neck it. It will not amplify your shaking the short the rods is. Also drag the rod when you start your arc, don't stab it, strike it like a match.Miller bobcat 225g  - spoolmatic 1Mm250 - 30a spoolMiller spectrum 375Thermal arc 95 Everlast Ex 250As the boiler turns, these are the days of our lives
Reply:OK I just passed my 6g test. Saw only a spot of porosity while I was grinding down the caps.The test was on schedule 160. But monday I am testing for a company on schedule 40 (x-ray).I was told that running 7018 too cold would cause porosity. I am afraid to run it at 95amps like Ido when capping 160. Would lowering the amps be a problem with porosity? Has to be 100% since its going to be x-ray.
Reply:I would not turn down the amps on sch. 40. Run the same heat... The trick is to allow the piece to cool to the touch between passes. Always try to run as hot as possible to avoid any inclusions. Its an xray test so just keep it clean... Youll do fine.