Help with RMD root and fill

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I've just started learning to use RMD for root and fill. I would like to know what other welders are doing as far as machine settings, joint prep ect.... I'm welding on 6" sch 80 pipe, 1/8 land & 5/32 gap. Wire speed is 250 arc length 0.0. I'm new to this process so any advice on setup or technique will be helpful
Reply:That RMD is a pretty slick process for putting a root in.   Not sure I'd be using it for anything beyond that though.  Don't have time now but this week end I'll see if I can't find the note book I've got the parameters for when I was doing it written down and give you some settings.   Which machine are you using?
Reply:WOW! That’s about the nicest root pass I’ve ever seen! Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:I'm using a PipeWorx 400. I was wrong earlier about the fill. Root is RMD . Hot and fill is with the Pro pulse. Then FCAW cap. Any info on the RMD & Pro pulse would help
Reply:Originally Posted by CEPWOW! That’s about the nicest root pass I’ve ever seen!
Reply:E. Boat
Reply:Originally Posted by steelsurgeonAgreed....that is a beautiful root pass, but you'd crap if you saw the roots the we achieve with purged pipes and consumable insert rings using tig....Rich
Reply:Originally Posted by tiginatorI'm using a PipeWorx 400. I was wrong earlier about the fill. Root is RMD . Hot and fill is with the Pro pulse. Then FCAW cap. Any info on the RMD & Pro pulse would help
Reply:Here you go, start watching videos and reading at the links on this page.   https://search.yahoo.com/yhs/search?...orx+400+videos
Reply:With 0.035" solid wire in  5G position0.0 Arc Length  170 IPM wire feed speed   1/16" land 1/8" to 5/32" root openingWith 0.035" solid wire in  1G rolled position0.0 Arc Length  200 IPM wire feed speed  Knife edge to 1/16" land, 1/8" to 5/32" root openingWith 0.045" solid wire in  5G position0.0 Arc Length  140 IPM wire feed speed   1/16" land 1/8" to 5/32" root openingWith 0.045" solid wire in  1G rolled position0.0 Arc Length  175 IPM wire feed speed  Knife edge to 1/16" land, 1/8" to 5/32" root openingYou can adjust +/- 10% on these wire feed speeds to suit your tastes with no adverse affects.  +/-0.2 on Arc length as well.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:@ tiginator,You lucked out dude (A_DAB joined in).   He certainly made my learning curve on learning the RMD process (and figuring out the PipePro 450 machines workings) a lot gentler than it would have been if he hadn't taken the time to talk to me about it.
Reply:Actually a standard roll welded MIG root at 10 o'clock can look even better than that. Roll welded MIG roots are one of the easiest welds to do. What takes time is trusting your root went in so you're not constantly checking with a flashlight through the un-welded gap. Usually in a shop setting you don't put a land on the pipe for MIG roots but some guys will use a 1/16" land if they're doing a test or it's real thin wall. Gap is usually 5/32" up to about 4" and 3/16" gap for larger pipe and vessels. Normally about 18 volts and 110-120 amps. Not sure what the wire speed would be to get those amps. Don't have experience with RMD but I think it's supposed to make it easier for out of position MIG roots and is faster.
Reply:Isn't one of RMD's advantages that it can put in a stainless root without a purge?
Reply:OK, found that note book.....That root pass I posted a picture of that was done in the 6G on 8" sch. 40........035 ER70s-690/10 shieldingland 1/16"root opening 1/8"RMD mode, down hillWFS: 245Trim: 52AC (arc control): 25Also did some 6" sch. 80 in the 5G rolled using a positioner with 1/16" land and 1/8" root opening using .045 70s-6Settings for the RMD root wereWFS: 150Trim:50AC: 25I must have timed my root pass (one go start to stop) because I had a note that my travel speed was 4.82 ipm.Switched to ProPulse mode for the fill and cap using the same wire and it shows I usedWFS: 230Trim: 56AC: 25on the first fill pass and then turned the WFS down to 210 for the second fill pass and cap.Also see where I did a rolled 8" sch 40 RMD root with .045 solid wire using 1/16" land and 3/16" root opening using a WFS of 140, Trim setting of 50 and AC setting of 25.   My notes say that root took 4 minutes 36 seconds start to stop.
Reply:Originally Posted by OldSparksIsn't one of RMD's advantages that it can put in a stainless root without a purge?
Reply:Here's an RMD open root done on plate using .045 metal cored wire (FabCor 86R).WFS: 110Trim: 50AC: 23shielding 90/10land 1/16root opening 1/8"pulled
Reply:Here's the fill passes on that plate using the same wire but switching over to Pro Pulse mode.WFS: 140Trim: 50AC: 23pushed
Reply:Here's some more good stuff from Miller on pipe welding techniques using the RMD and ProPulse processes.http://www.millerwelds.com/resources...nd-techniques/
Reply:This is what you really want to print off, study (and take to work for reference).   It gives recommended parameter settings for both the PipePro 450 and PipeWorx 400 machines.   https://www.millerwelds.com/pdf/PipeWeldingHandbook.pdf
Reply:I demo'ed one of those machines and got pissed because all i could think is how it was going to drive the price of a good welding hand into the dirt.   IT made it to easy to root and cap.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Well I got some reading ahead of me, videos to watch and a whole lot of welding to do. Thanks for the info. I'll post back with results soon.
Reply:Just an fyi.  The pipe pro is based on the axcess welder and the pipe pro is out of production.The pipe works is based on the invision welder. Same basic unit used in the MM350P XMT 450 and the invision units. Both units have micro controllers and are software controlled.
Reply:Originally Posted by HT2-4956I think I've heard (read) that claim also.   And while that might just be possible under laboratory testing conditions I'm not to sure I'd want to depend on that under real world field (or shop) conditions.
Reply:Originally Posted by tiginatorWell I got some reading ahead of me, videos to watch and a whole lot of welding to do. Thanks for the info. I'll post back with results soon.