What a difference

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As most of yo know, I'm building the shop and plasma is a big issue with all the cutting I have to do at the ranch. I was using the Longevity on a pancake but used it for the first time on a 60 gal, 2 stage this evening and what a difference. I know you all have been doing this for awhile but to a relative beginner, the joy of new discovery is a wondrous thing. It's like being a kid on Christmas morning again. I also used his plasma cutter which is different than the one I have and and, again, what a difference. He was explaining the differences in generator power v. wall power and cfh differences and things are beginning to make sense. I love understanding things when "the light finally comes on". Nothing you all probably didn't already know but I just couldn't help sharing revelations with the people who have been patient enough to teach me things. Again, BIG thanks to all of you here.
Reply:Well yeah. The specs for my air supply changed dramatically as did my choice for lines, filters, dryers and the like. He's been doing his shop work for awhile now and has gone through the experimental stages of finding what works and what doesn't. It's nice to have access to people who don't have an axe to grind either way, aren't married to red or blue and don't think that just because it's Chinese or marked HF, it automatically sucks. Good and bad in everything. Just have to figure out which is which.
Reply:By far, the majority of calls that come into Hypertherms tech service group in regards to cut quality, misfiring, not being able to achieve "book" cutting speeds, etc....turn out to be air pressure issues. Most plasma systems have pressure switches that are designed to shut off the cutting arc before damage (due to low pressure) occurs to the consumables or to the torch body, however before the air pressure gets low enough to activate the low pressure switch, cut quality will deteriorate.Keep in mind that the plasma rc is an ionized stream of air forced through a nozzle orifice. The nozzle increases velocity, shapes the arc into a perfect column, and increases the energy density in amps per square inch. Whe air pressure is too high at the nozzle orifice, expect rapid nozzle erosion as the air pressure strips away the boundary layer of cooler air prticles that are designed to make the nozzle last longer. If the air pressure is too low, you first lose energy density in the arc, which acts just like turning down the power (Amps) back at the power supply Even lower torch air pressure and you start getting some internal double arcs from the electrode to nozzle, then the nozzle to the plate....this will cause rapid nozzle wear and "stiction" (torch sticks to material while dragging), which produces very ugly cuts.Often the user tells me that their air pressure is 120 psi entering the plasma.....I then ask "where is the pressure gauge that you are reading this pressure at".....and almost always the gauge is located at the compressor, with 25 to 50 feet of hose, maybe a filter or two and some pipe fittings in between. If a gauge is located at the inlet to the plasma.....it will read the same pressure when there is no air flowing at the plasma (static pressure), but when you trigger the torch (dynamic flow) you will see the gauge at the plasma drops, sometimes rather dramatically. This pressure drop is caused by the length of the hose, the filters, the pipe fittings that cause restriction, and often the plasma does not recieve adequate flow to satsify the needs at the torch.Put a gauge at the inlet, monitor it periodically with air flowing! his will ensure more consistent results with any air plasma system, and will help troubleshoot and solve air flow/pressure issues.
Reply:Interestingly, Ron, my neighbor, said the same thing this morning at the fence line where we usually see each other and talk. He built and uses an almost identically-configured device that lets him know the exact pressure he's getting at the nozzle. A retired Lockheed aeronautical engineer, he's a wealth of information and his views on the ill-effects of water on all things pneumatic is fascinating. Before speaking with him, I had no idea how important dry air is to the life-span and the performance of tools and especially the performance of plasma cutters. He sent me to a site I looked at last night and re-read this morning and I thought some of you would find the information interesting too. http://www.jtdryers.com/Last edited by jlames; 10-18-2013 at 12:36 PM.
Reply:Here is a link to an article I wrote describing the effects and some of the cures for contaminated compressed air systems.   Link: http://www.achrnews.com/blogs/16-gue...plasma-cutting  The effects of moisture will vary from one model of plasma system to another, with some torch designs that experience very short consumable life with relatively minor moisture contant, while others are very minimally affected. Design of the torch makes a big difference.  Interestingly it is relatively common for plasma system users to over do air system preparation.....too many filters can create restrictions and air starvation, which can amplify your cut quality issues.Jim Colt   HyperthermJim Colt
Reply:Thanks for sharing the good info.  That is so cool that you have a retired Lockheed aeronautical engineer willing to share knowledge as a neighbor.
Reply:Yeah, I'll trade my tattoo artist neighbor for your aero engineer neighbor..............please.
Reply:It's why we're retiring to this place... and in California of all places... and Southern California at that. He's just like everyone else around here; once the go-to-guy in their particular fields of expertise and now you wouldn't know them from the two guys in the cranberry field commercial!!! Our other neighbor is Terry Leonard, every actor you never heard of because he was their stunt double. Now he's a 2nd Unit director but spends his home time at his ranch helping neighbors. We have our share of tattoo artists too but even they are committed to helping their neighbors. As an aside on Ron, the aero engineer, stay away from the Dreamliner if you have to fly commercially. In short, not ready for prime-time!
Reply:As a former Air Traffic Controller, I stay away from flying all together. With the number of planes in the air and the drastic reduction in knowledge at the controller level, I'm surprised that we don't have more incidents than we do. Good to know about the Dreamliner, and this isn't the first time I've heard that.
Reply:In my experience about all AG based communitys  are good about " neighboring "  each member  as long as said member " neighbors " back in some fashion or form . Strangely enough  it seems to be part of that  independent mindset to not mind the freewheeling dependency  on each others skillets and knowledge. Typically if a skill is needed someone on a nearby place both has it and will take the time to share it , knowing how many times in the past they have been and in the future they will be  the person asking for help or information .  Heaven help the " outsider "  that comes in thinking they don't need help  or  know better because they read it in a book though .   LOL
Reply:At the old family farm in Ohio, a neighbor volunteered to drive my aunt and cousin to their doctor visits.  The fellow is 100 years old!  We used to swim in his pond over 45 years ago."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Yeah, flying, especially in the LA Basin. I've known my fair share of ATC over the last 40 years from tower to center and they all say virtually the same thing you are. It's never easy over-riding a control directive in the air but I've had to do it twice and go through the nightmare of "please contact tower when you land... do you have the number?" and the  explanations afterward, paperwork, tape reviews and in one instance a hearing and both times it's been within the last 2 years and both of the controllers had less than a year on OTJ. One was when I was in solid IMC and my gut and GPS were telling me exactly the opposite of what ATC was directing. Anyway, story for another time but you're right. As to FarmDad, you're right there too; especially with so many city-folk retiring to what they think the "country" is with alot of money in their pockets. They're simply not used to the "see-someone-needs-help-and-help" attitude but they sure are long on expecting 4-star service at the local diner without so much as a "please" or "thank you". Helping others is in the DNA. It's not something you can teach I don't believe.
Reply:My plasma cart has it's own dedicated clean hose to a simple bulb separator and then a Motor Guard rolled media filter as final before the plasma machine.  Works great, and always consistent filtered air.And you guys are making me home sick.  I was born and spent my early life in a single wide trailer on a dirt road in NW AL.  About 1/4 mile from "dry creek" (not much farther from "little bear" and/or the Tennessee River"), near "Hawk Pride Mountain".  If that don't make you hear banjos playing, nothing will.  I remember when I was about 8, one of the neighbors got "down in his back".  My grandfather, father, and I along with some other neighbors went over to "take in his silage".  I was young, and to my memory it must have been over 100 acres of silage, but really was probably no more than 10 or so.  When I wasn't able to help with parts of that task, I was sent to take care of his horses.  Before I left AL in the early 90s, I had my own "small lot" of 26 acres near the TN/AL line.  Simpler times.  Now I'm a "Senior Computer Programming Consultant" working in Phoenix AZ.  My what a wondering path that has been.  In the last few years I've been thinking more and more about retiring to a 10+ acre plot somewhere far outside the city.
Reply:We're only about 30-miles north of Los Angeles but it might as well be a world away. 5-20 acre lots are small to average and 100-acre lots are still co mmonplace. People here still band together to fight to keep development out. Alot of attorneys live out here or have retired out here so the legal representation against the Kaufman and Broads and other real estate developers of the world is rather built-in because they have vested interests. And alot of entertainment industry people also live or have retired out here and their political influence and money really helps as well. Attorney or artist, doctor or dump-truck driver, we're all the same on the dirt roads of life around here.And hey baddog, you need to look up Kevin Caron out there. What a great guy and a really knowlegable welder and metal artist. He and his shop are  somewhere around you in Phoenix.
Reply:His studio is just S of where I used to live in Paradise Valley.  I'm now over 30 minutes N of there near the Pinnacle Peak Mountain Preserve.  I've got a 1.3 acre "Horse Property" (zoned Ag, and no HOA, which is one of the reasons I bought it).  Folks around here consider that HUGE, but to me it feels the bare minimum to not feel like I'm crammed in (as it felt in PV).
Reply:Great place. We do alot of Cowboy Mounted Shooting competition that takes us out to Westworld in Scottsdale. Lots a good horse people out there.