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I finally got everything set up to use my new Torch. The cut starts out fine then the quality deminishes with incomplete cut and excess slag. While there is a strong possibility that this is "operator error", it also looks like the compressor may not be "keeping up". The rating on the compressor meets the requirments stated by the torch manufacturer, but the tank is only 13 gallons. I'm wondering if it is the tank size that is the problem.Will adding additional storage (say an additional 20 gallons) for the compressed air correct the problem, or should I just buy a larger compressor?Any tips, suggestions, or possible remedies would be greatly appreciated.Timm9Victor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:I would say yes, you need a larger air compressor to keep up with the air demand. Otherwise, your cuts will be very short - you'll have to stop, wait for the air pressure to build, then resume the cut.John - fabricator extraordinaire, car nut!- bleeding Miller blue! http://www.weldfabzone.com
Reply:Thank you John!I appreciate the response.Do you think 30 or so gallons and a rating matching the manufacturers specs will work?Merry Christmas!Timm9Victor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:You are welcome. Yes, spec. the compressor to at least the manufacturer specs. A nice 60 gallon unit can be found for close to the 30 gallon units. Check around or online. Northerntool has some good prices.John - fabricator extraordinaire, car nut!- bleeding Miller blue! http://www.weldfabzone.com
Reply:I think I would do a small test first. Borrow a larger capacity air compressor, (or bring your machine to a larger air compressor)This would be the cheapest way to diagnose the problem and be sure of a solution. Also, you can put an additional compressor, plumbed to yours to increase your cfm's. Think maybe , rental??Just my opinion, not from a book, just from the road.Howes Welding Inc.www.howesweldinginc.com
Reply:It might also be getting too much water into the cutting head. Do you have any air/water seperator on the air line now? If you put on the blow gun fitting, can you see moisture spraying out when you hit the button?John - fabricator extraordinaire, car nut!- bleeding Miller blue! http://www.weldfabzone.com
Reply:Have you considered plumbing a 10 gallon portable air tank onto the discharge of your air compressor to provide more surge volume?TeddCoHTP Microcut 400 & Invertig 160DC Smith Dual Guard MD-510 OA Rig Lincoln SP135+ Hobart Stickmate LX 235/160
Reply:Thank you for the responses and suggestions.I currently have two filters and water seperator that was installed prior to using the torch.I have considered taking the torch to a bigger compressor but I live in a very rural area and with the holidays, every body traveling, I'm not sure I can get next to a larger compressor before the end of the "after Christmas" sales and the price of a new compressor goes up.I had considered adding a "portable" tank, or finding a "dead" compressor and using the tank for additional storage. My concern was that the largest portable I could find on-line was 11 gallons, and would this not be enough to solve the issue? If 11 gallons will still be border line, am I better off saving the $40 to $50 for a portable tank and putting it towards a new compressor?I'm not trying to be "cheap", just don't want to spend money that does not solve the issue, not to mention everything is an hour or so away "drive time" to purchase, portable tank or new compressor.I was hoping that someone had "been down this road" and could save me the trail and error part of the education...Timm9Victor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:You should be able to rent a small portable engine drive compressor from a local rental place for about $30 or so, maybe less for a half day. Before I had my large engine drive compressor I rented one like this from time to time and it worked very well..... You need to compare the rated CFM and pressure of the compressor to the needs of your machine. I have a Miller spectrum 1250 (I think that's the model) and I think it has like a 5- 6 CFM @ about 60 lbs or so as a requirement. The machine I listed has a 9 CFM@100 PSI, with 8 gallons of tank.http://www.dewalt.com/us/products/to...productID=3105How long are the cuts your making time wise..... are they taxing the duty cycle of your machine?_________________Chris
Reply:First, make sure you have the correct diagnosis of the problem by having someone watch the pressure guages as you make a relatively long cut. I do believe that a drop in air pressure is probably your problem, but it's always best to confirm such guesses before investing in an expensive solution. The pressure out of the regulator at your plasma cutter, not the pressure out of the tank, is the one to watch. Even with a large compressor, there will be some drop in tank pressure as the cut progresses until you reach the balance point between the compressor delivery and the compressor output pressure.Second, assuming that a pressure drop and not moisture is, in fact, your problem, the appropriate solution is more CFM, not a larger tank. Sure, a larger tank will carry you for a longer period, but you will always be limited at some point by the compressor. Perhaps with a large enough tank the limit will be beyond your personal capacity to continue the cut without a break and the larger tank may, therefore, be an acceptable solution. But it is a stop-gap measure, not the proper solution. A larger compressor or an additional small compressor in parallel with your existing compressor is the proper solution. I think you can get a tankless, non-oil lubricated compressor to supplement your present compressor for well under $100.If you want to go the tank route, figure that the percentage increase in tank capacity is ROUGHLY equal to the percentage increase in cut duration. (It's not an exact proportionality because the compressor is working the whole time to keep up. It would be an exact proportionality only if the compressor was off at the start of the cut.) If you double the tank capacity, you will about double the cut duration until cut quality deteriorates.If you add 20 gallons of storage to your 13 gallon rig, you will increase the quality cut duration by the factor (13+20)/13, or about 2.5 times.awrightLast edited by awright; 12-24-2006 at 01:09 AM.
Reply:Thanks to all of you for the excellent suggestions an feedback.The metal that I was cutting was less than 1/8" thick and the intended cut was approx. 9 inches long which I don't believe was "taxing" the duty cycle. The quaility fo the cut diminished after approx. 3 to 4 inches.I spent quite a bit of time researching compressors last night and after reading reviews, problems, and comments on contractor type web sites, I found quite a few complaints about compressors not even coming close to the manufacturers CFM ratings. I believe this is the case with my compressor. While my compressor has been a trouble free unit, after looking at formulas for amps, HP, etc. it is pretty evident that there is no way my compressor puts out anywhere near what it is rated at.I will try the torch again and have someone watch the guage on the torch itself and see what happens. I suspect that previous comments about the CFMs will prove very accurate. Thanks again! You guys are awesome!Wishing everyone a very Merry Christmas!!Timm9Victor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:Originally Posted by timm9Thanks to all of you for the excellent suggestions an feedback.The metal that I was cutting was less than 1/8" thick and the intended cut was approx. 9 inches long which I don't believe was "taxing" the duty cycle. The quaility fo the cut diminished after approx. 3 to 4 inches.I spent quite a bit of time researching compressors last night and after reading reviews, problems, and comments on contractor type web sites, I found quite a few complaints about compressors not even coming close to the manufacturers CFM ratings. I believe this is the case with my compressor. While my compressor has been a trouble free unit, after looking at formulas for amps, HP, etc. it is pretty evident that there is no way my compressor puts out anywhere near what it is rated at.I will try the torch again and have someone watch the guage on the torch itself and see what happens. I suspect that previous comments about the CFMs will prove very accurate. Thanks again! You guys are awesome!Wishing everyone a very Merry Christmas!!Timm9
Reply:timm9 said, "...it is pretty evident that there is no way my compressor puts out anywhere near what it is rated at." Well, timm9, you have to read the fine print very carefully. The box will often be emblazoned with, "X CFM" and "130 PSI," but in two point type on the bottom of the box it will say, "x cfm at 40 psi." The home air compressor (and the shop vac) market seems particularly rife with deceptive advertising, particularly with physically impossible horsepower claims.Reminds me of the C-H pressure washer I bought (fortunately at salvage) that bragged on the box, "2500 PSI*," but after I got it home I saw that the fine print said, that their super-duper oscillating nozzle made it "...clean like a 2500 PSI washer," but this model actually only put out 1800 PSI. I expect to have wised up to all the scams by the time I'm on my deathbed.But, back to the issues at hand: Rojodiablo, what evidence are you seeing in the discussion to make you think the problem is hose/fitting size? Granted, the cut problem seems to arise pretty quickly (3 to 4 inches in 1/8" plate), but since there is no air reservoir other than the volume of the hose downstream of the tank, I wouldn't expect the problem to take that long to show up if the problem was hose or fitting size.The proper way to evaluate the problem is, of course to measure pressure at the tank, the cutter air regulator outlet, and the torch connection and see where the pressure drop is occurring when the problem arises. With that information in hand, the solution will be obvious.awright
Reply:Originally Posted by awrighttimm9 said, Rojodiablo, what evidence are you seeing in the discussion to make you think the problem is hose/fitting size? Granted, the cut problem seems to arise pretty quickly (3 to 4 inches in 1/8" plate), but since there is no air reservoir other than the volume of the hose downstream of the tank, I wouldn't expect the problem to take that long to show up if the problem was hose or fitting size.The proper way to evaluate the problem is, of course to measure pressure at the tank, the cutter air regulator outlet, and the torch connection and see where the pressure drop is occurring when the problem arises. With that information in hand, the solution will be obvious.awright
Reply:Originally Posted by awrighttimm9 said, "...it is pretty evident that there is no way my compressor puts out anywhere near what it is rated at." Well, timm9, you have to read the fine print very carefully. The box will often be emblazoned with, "X CFM" and "130 PSI," but in two point type on the bottom of the box it will say, "x cfm at 40 psi." The home air compressor (and the shop vac) market seems particularly rife with deceptive advertising, particularly with physically impossible horsepower claims.Reminds me of the C-H pressure washer I bought (fortunately at salvage) that bragged on the box, "2500 PSI*," but after I got it home I saw that the fine print said, that their super-duper oscillating nozzle made it "...clean like a 2500 PSI washer," but this model actually only put out 1800 PSI. I expect to have wised up to all the scams by the time I'm on my deathbed.But, back to the issues at hand: Rojodiablo, what evidence are you seeing in the discussion to make you think the problem is hose/fitting size? Granted, the cut problem seems to arise pretty quickly (3 to 4 inches in 1/8" plate), but since there is no air reservoir other than the volume of the hose downstream of the tank, I wouldn't expect the problem to take that long to show up if the problem was hose or fitting size.The proper way to evaluate the problem is, of course to measure pressure at the tank, the cutter air regulator outlet, and the torch connection and see where the pressure drop is occurring when the problem arises. With that information in hand, the solution will be obvious.awright
Reply:Originally Posted by BruceI am guessing that is why everyone always says get a bigger compressor than you actually need? Also having someone there to eyeball your guages while cutting could be a great help. Wouls another storage tank be similar to having a "two-stage" compressor?
Reply:Originally Posted by BruceI am guessing that is why everyone always says get a bigger compressor than you actually need? Also having someone there to eyeball your guages while cutting could be a great help. Wouls another storage tank be similar to having a "two-stage" compressor?
Reply:I thought I would give an update.It was the compressor. After determining that I needed a new/larger compressor I started doing research and also discovered that I also took very poor advice and plumbed my garage and shop area for compressed air in PVC quite a few years ago. At this point the PVC has been torn out, and all the materials have been purchased to install a compressed air system in copper. God help anyone else if you have to buy any copper
the 1 inch type L was $5.00 a foot after tax! The elbows, etc. were worse! Im also awaiting the delivery of the new compressor (Ingersoll-Rand) and have purchased everything I need to wire in the 220 service for it. I will have the wiring and plumbing done (as much as I can do until the compressor arrives) next week. CFM will not be an issue with the new compressor which is rated at 18.1! Needless to say, this has been a very expensive education!Thanks again for all the help! You guys are awesome!TimVictor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:Congratulations Tim,It sounds like you have been to the cleaners as well? $5.00 a foot!Bruce The Welding ChefLincoln Weld-Pack 3200 NORWELD StickStanford Hill Farm
Reply:Yeah...Thank God my wife is supportive!TimVictor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:Originally Posted by timm9Yeah...Thank God my wife is supportive!Tim
Reply:Originally Posted by lorenzoOr she has something in mind for herself " Tim remember when you had buy all that expensive copper pipe the fittings and that compressor? Well I was thinking......................."
Reply:Originally Posted by timm9Chris,I have been married to her for a long time and she has never, ever, done that! I'm extremely lucky in that respect! I have to push her into buying anything for herself.Tim
Reply:Sounds like you are going to have a class A system. You've probably checked it all out, but just as a reminder, there are definite principles of sloping the lines, providing drip stubs at vertical runs, drying the air for plasma use, etc., that are often forgotten in pneumatic plumbing. Applying those principles will help in minimizing contamination of your air. A book on pneumatic system plumbing would be a good investment.awright
Reply:Originally Posted by awrightSounds like you are going to have a class A system. You've probably checked it all out, but just as a reminder, there are definite principles of sloping the lines, providing drip stubs at vertical runs, drying the air for plasma use, etc., that are often forgotten in pneumatic plumbing. Applying those principles will help in minimizing contamination of your air. A book on pneumatic system plumbing would be a good investment.awrightCool, glad it worked out for you!John - fabricator extraordinaire, car nut!- bleeding Miller blue! http://www.weldfabzone.com
Reply:Thanks for the reminders!The plumbing and wiring are done (as much as can be done until the unit arrives) and I did include the proper fall, and drip stubs with valves at each verticle drop. The main lines are 1 inch, and the drops are 3/4 inch. In addition, the drops leave the main line and go up before turning and going down.Thanks again for everyones help! It is greatly appreciated!Timm9Victor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:Excellent job!awright
Reply:Originally Posted by timm9Thanks for the reminders!The plumbing and wiring are done (as much as can be done until the unit arrives) and I did include the proper fall, and drip stubs with valves at each verticle drop. The main lines are 1 inch, and the drops are 3/4 inch. In addition, the drops leave the main line and go up before turning and going down.Thanks again for everyones help! It is greatly appreciated!Timm9
Reply:I have had my shop air supply system plumbed with 3/4" sch 40 PVC for ten years with no problems. I've worked in shops that used it for 20 years, so it was good enough for me. The shop at my business is run in black iron and is engineered in mutiple sizes (2" to 3/4") to get aorund the 60X100' building to the 15 drops. At home, I get a maximum 100PSI from my little 2HP 20 gallon compressor out behind the garage and have three runs (L,R and Middle) dropped in with line drains on each run. I have a line pressure regulator on the system, and a water filter on the system and another at the plasma. I have no problem running my Plasma for short to medium cuts, run air tools, blow gun and whatever else I need to do. It is too small for anything serious, but works fine for the ocassional cutting and knocking off nuts and stuff.If you are going to be doing any serious work, you need a larger tank (60 gal.) and a large enough compressor to keep it full within the motor's duty cycle or you will burn it out prematurely. Proper sizing the compressor and motor are dependent on how much work you intend to do in what amount of time. Let alone the constant noise from running full time. The only way to know this for sure is to compute your CFM's (your needs may change), or buy overkill and just forget about ever worrying about air supply again.SIDEBAR- I deliberetly chose 3/4" instead of 1/2" to add a bit more volume to my system, due to the small tank.I bought this Campbell-Haufield compressor at JC Penny's over thrity years ago, when they were competing with Sears for tools. I had to change the belt once, oil every few years. Anyone here old enough to remember that?Hobart 140 Handler w/ gasHyperTherm Powermax 380 Plasmaoxy/acetylene
Reply:I believe the prohibition of plastic pipe for pneumatic applications has to do with the hazard of the pipe shattering and throwing scraps of pipe around. This is not as much of a hazard with malleable materials like iron or copper pipe.We all do things that violate safety guidelines at times, but I don't think we should be encouraging people who may not be familiar with the reasons for the guidelines to do the same. Additionally, many people run their compressors at 125 PSI cutoff.awright
Reply:PVC is -not- supposed to be used for air lines. Yes, I know that some folks have run their shop lines in PVC and been fine for years. Still doesn't mean it's right.PVC gets brittle over time and in cold temps. Compressed gases store a -lot- of energy. Compressed gas in brittle PVC pipe = sharp brittle shrapnel.See http://www.osha.gov/dts/hib/hib_data/hib19880520.htmlRun metal lines (copper or black iron or new-fangled expensive aluminum with the fancy-dancy fittings or whatever). Or run pneumatic hose.No PVC pipes for compressed gases!
Reply:I totally agree that PVC is not the recommended material for compressed gas lines. I am just stating that I used it and I've worked in places that have used it in the past. Back then, it was quite prevelant in many shops until OSHA intervined due to tested safety concerns. When it gets old, it does become more brittle. Also, if exposed to sunlight, it deterorates even quicker. When I replumb, I will use iron or copper.Hobart 140 Handler w/ gasHyperTherm Powermax 380 Plasmaoxy/acetylene
Reply:It was not my intent to start a 'debate". I was only sharing what I had discovered by accident. During my 'research" I discovered quite a few stories about how dangerous PVC could be under the right circumstances. Spending almost $400.00 in pipe and fittings was the last thing I wanted to do after buying an expensive compressor. In the end it's like my wife said, "It's alot cheaper than a trip to the emergency room for you, or one of the kids". The last kids visit to the ER was $6,000.00.The old PVC system had been up for 7 or 8 years and it gets very cold here (it will be below 20 degrees tonight) in the winter. It was only a matter of time until something failed, or was bumped while under pressure. I have read where plenty of people are currently using PVC. I was just not willing to chance it.Thanks again to all!Timm9Victor O/AMillermatic 210Hypertherm 380Miller Thunderbolt
Reply:Wow! Excellent, informative post, MoonRise. Thanks for the information. Supports my intuition.awright
Reply:I thought most plama's cut off when the pressure dropped to low for a quality cut (mine does) I keep it at around 80psi and if it drops past 70psi it'll cut out. I still get a good cut on 10ga at 70psi.DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:I hope this is sufficiently related to this thread. How would one go about building a plasma cutting air source as portable as possible? The Hypertherm 600 requires 6cfm@72psi. If a portable compressor spec is capable of that, would the tank even be necessary? Or would the air "pulse" too badly straight out of the compressor even with a regulator? If so, would it be possible to simply replace the original two, four, or whatever sized tank with a litre sized storage vessel? The idea here is to have an air sourse that is basically as portable (size and weight) as the plasma cutter itself that could be plugged into any 110. Maybe this animal already exists? I couldn't locate it on the net.
Reply:The Hypertherm 600 requires 6cfm@72psi. If a portable compressor spec is capable of that, would the tank even be necessary? Or would the air "pulse" too badly straight out of the compressor even with a regulator?
Reply:So for straight lines, a clamped ruler would be a good idea, other cuts might need a made-up jig?Bruce The Welding ChefLincoln Weld-Pack 3200 NORWELD StickStanford Hill Farm
Reply:Originally Posted by BruceSo for straight lines, a clamped ruler would be a good idea, other cuts might need a made-up jig?
Reply:Sounds like the way I am headed, always liked the predictability(sp) of a template.Bruce The Welding ChefLincoln Weld-Pack 3200 NORWELD StickStanford Hill Farm |
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发表于 2021-8-31 23:01:06