Cool $544 Motor

admin

Last week the plant manager told one of the warehouse guys to make a dead 24" model HP Port-A-Cool "disappear" that had a bad motor.  A replacement costs $544 and they just put a new circulator pump ($289) in it not too long ago.Didn't have to ask me twice if I was interested and Thursday night it got loaded on top of the 'burban and brought home.Looking it over I figured a $89 box fan could be rigged to hang in place of the original if needed but what fun would that be?  So yesterday I took another look and a few measurements and set about on a rebuild of the original.  What did I have to loose but some time?Original aluminum housing corroded and seperated on one end allowing misalignment which caused interference between the rotor and stator.Finished splitting the housing to release the stator for cleaning.ID of original housing was 5-1/4" and just under depending on location and OD (minus fins and channels) around 5-5/8".  A piece of 5" schedule 40 CS pipe from the storage building proved to be the perfect material for a new housing.5" long section with OD trued up and ready for finish boring.A couple hours later and the test fit.  I don't have measuring instruments greater than 5" so fitting the counter bores on each end for the end plates was trial and error.  I thought I blew it and wasted the piece as I took too big a cut - just one more I think was the thought at the time - and the ID wound up being a snug 'slip fit' for the stator.  Not good as it needs to be pressed in.  But wait - there's more!  The motor is a TEAO (Totally Enclosed Air Over) which relies on air flow over its housing for cooling and to give it a fighting chance I'll need to add some cooling fins as well as the mounting bolts (the welding part of the project ) and no doubt the new housing will shrink as a result.  Now I'm beginning to wonder if the ID is going to be big enough.Stand by for post #2 . . .Last edited by duaneb55; 08-09-2010 at 12:36 AM.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:. . . showing the new housing with cooling fins and original mounting slide bolts also welded to the housing which shrunk to a perfect press fit for the stator. . .. . .which needed a special pressing tool to get the job done.  Used the left over section of 5" pipe turned down to clear the ID of the new housing and still push against the stator laminations.All pressed in to the proper depth and ready for final assembly.A quick trip to TSC for three 6" long 1/4" carriage bolts (cap screws stop at 5") to use as tie bolts to hold it all together and mounted it back in place.  Used two 1/4" flat washers on each mounting stud to replicate the original housing-to-mount dimension.All buttoned up and the final results. . .[ame]http://www.youtube.com/watch?v=zfp5C191Dn0[/ame]Thanks for looking.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Duane, yah never cease to amaze! What a job guy, great recovery. "The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Very nice Duane.  I think examples of things like this that made me want to get my lathe.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Is that one of those ones with the radiator?  Could have gotten fancy and water cooled the motor maybe.My name's not Jim....
Reply:Nice fix. I bet that cooler will come in handy right about now
Reply:That's the expensive variable speed model, hellofa catch Duaneb!I have the 3 speed model (much cheaper) and use it often when I can't close up the shop and run the air. I always use it when gouging and stick welding if it's miserable out (like now)The best prices I've seen for media replacement is usually direct from mfg but northern tool is very low too.MattEdit; forgot to mention the super fix, and manuals are online.
Reply:Outstanding, Duane!!  That is truly inspirational !!!  Member, AWSLincoln ProMIG 140Lincoln AC TombstoneCraftsman Lathe 12 x 24 c1935Atlas MFC Horizontal MillCraftsman Commercial Lathe 12 x 36 c1970- - - I'll just keep on keepin' on.
Reply:That is amazing, I wish I had the knowledge, skill and tools to be able to see a cracked motor housing and decide to make my own.  And that looks like a nice setup you got for the price of the pipe and some flat and some time.Great job.
Reply:Thanks to all for the comments.  It was a fun challenge although a little disconcerting at one point as I explained.How is that lathe coming along Mark?The water cooled idea did cross my mind boostin but it didn't stick around very long. I do need to get some paint on it to keep this one from corroding away.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:79˚ high59˚ LowWhat is a Porta Cool?Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Originally Posted by Broccoli179˚ high59˚ LowWhat is a Porta Cool?
Reply:Originally Posted by Broccoli179˚ high59˚ LowWhat is a Porta Cool?
Reply:Originally Posted by Broccoli179˚ high59˚ LowWhat is a Porta Cool?
Reply:Been using it for little projects, have to get a replacement gear before I can use the power feed, so it's coming along fairly well.  Slow but sure.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Great job, Well done.You might consider giving it a coat of black paint. It will cool better, You don't have as many air fins as there was before. Black will increase your rate of heat transfer.
Reply:well even if it needed a 600 motor it still would have been half price or better.  The fact you made do with in stock materials is even better. The ship repair company we do some work with just bought a pair of "intrinsically safe" port-a-cools $12,000 EACH!!!   They are going to use them to keep the guys alive while they're steaming out the fuel tanks that need repair.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:Duane,Mark's lathe works great! It's making me a circle cutter for my plasma right now! I think we are two prototypes into it at this point, but he sure does keep busy. I think there are smokers on his brain permanently now.Awesome fix! Really!Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:Originally Posted by RancherBillGreat job, Well done.You might consider giving it a coat of black paint. It will cool better, You don't have as many air fins as there was before. Black will increase your rate of heat transfer.
Reply:Wow...Nice save Duane!!!http://all-a-cart.comWelding Cart Kits and accessories
Reply:Way interesting fix.   But a couple of points/questions.Info point:  Black "radiates" heat energy (that's real quotes there, not single quasi-quotes) pretty well.  See Black Body Radiation  http://en.wikipedia.org/wiki/Black_body  The black paint also affects the emissivity of the steel and slightly improves it compared to bare steel.  So 'black' absorbs -and- radiates energy (IR in this case mostly) pretty well.However, a layer of paint typically is, to at least a small extent, an insulator.  Glop on a thick layer of plastic (acrylic and most other paints fall pretty much into the 'plastic materials' category) and you are thermally insulating the base steel to some extent.So like most things in life and the universe, it's all about trade-offs.  Put on a thick enough layer of paint to protect the underlying steel from rusting and to slightly increase the thermal/IR emissivity of the object, but not so thick that it thermally insulates the steel.Next, a question.  No problem with the new steel housing causing problems with the motor's magnetic fields compared to the previous aluminum housing?And then an observation.  As already mentioned, your new motor housing has waaaaay less cooling surface area (fin area) than the original and the material is obviously changed from aluminum (thermal conductivity of ~120-180 for most aluminum alloys) to steel (thermal conductivity of ~50 depending on alloy).   The old housing had 40 fins estimated 1/2 inch high.  Two sides per fin, and the housing is estimated to be about 5 inches long.  That gives a total fin area of approximately 40 x 2 x 5 x 1/2 = 200 in^2Your new steel motor housing has 6 fins, estimated 1 inch high and still 5 inches long.  That gives an approximate fin area of6 x 2 x 5 x 1 = 60 in^2That's only 1/3 to 1/4 of the fin area on the new housing compared to the old.  And also ignoring that 'higher' 'fins usually don't cool as well as 'lower' fins because of the thermal resistance of the fin itself going from the heat source out into the cooling media.  Again, trade-offs on fin height for increased fin area but has more thermal resistance (greater thermal path/distance) over that height compared to lower fins.Also, all those partial fillet welds from the fins to the pipe/housing are -bad- from a thermal standpoint because you do not have a continuous thermal conductive path from the pipe/housing into the fins.  The heat from the motor flows into the outer motor housing (your piece of repurposed steel pipe), and then has to transfer from the steel into the (slight) air gap between OD of the motor housing pipe and then to the fins.  With that air gap space between the OD of the motor housing pipe and the fins, the thermal transfer has to be via the generally less efficient radiative and conductive transfer through the air gap compared to the waaay better thermal conductivity of steel through itself (the Zen of welding and heat transfer of Making-It-All-Be-One-With-Itself).The partial fillet welds from the steel pipe/housing to the fins are probably fine from a sturctural standpoint, but are horrible from a thermal/heat-transfer standpoint.So 1/3 the thermal conductivity (change from aluminum to steel) and 1/3 the cooling fin area and poor thermal paths from the new housing to the new cooling fins indicates to me that your motor internal temperature rise (wire, insulation, stator, rotor, bearings, etc) will be a LOT higher than the original.  Unless that original motor was hugely overdesigned from a thermal standpoint (not likely), I think you WILL have Problems (with a capital P) with the motor overheating in use.As you most likely know, a hot electric motor is NOT a happy electric motor.  The best laid schemes ... Gang oft agley ...
Reply:Dang MoonRise, I knew I should have tossed the whole thing in the dumpster!Grammatical and punctuation lesson 'duly noted'.First of all - not the same degree that you broke it down - everything you pointed out was considered leading up to the actual project.  OK, everything but the emissivity issue with regard to black painted-vs.-bare steel.A trip to TSC for additional fin material was considered however I elected to go with the 6 remaining pieces I had from a greater number for the fins as I was concerned about too much housing shrinkage if I included additional fins.  The same logic was my reason for the stitch welds in lieu of full length.  I thought about slowly finish welding the fins but chose not to out of concern for damaging the plastic stator slot insulators.Turns out after 2 hours of operaton Sunday afternoon in near 100°F the motor housing was barely warm to the touch so I'm going to call it good to go.  And even better yet once I give it a black paint job (thin) as I told RancherBill.As for the difference between the old aluminum and new CS housing, if the rotor could be supported and the stator prevented from rotated without it, the motor would still run.Thanks for the post.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:I agree whole heartedly on the fact that their entirely overpriced for what they are.   Im VERY VERY VERY surprised that someone hasnt started knocking them off yet.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:Like dad and I were talking about earlier, for the price we expected some better hardware (like the junction box in the 'wet' area, the frame, and the nuts/bolts)It sure does cool you off real nice though MikeConstans Fides et IntegritasLincoln Weldanpower 150 ACAirco Aircomatic MIGet CAV II w/ spoolgunMillermatic 30a wirefeeder
Reply:Helluva nice job Duane!Wow, very nicely done, Duane!Miller 211 MIGMiller 375 Extreme Plasma CutterMiller Maxstar 150 STL TIGOxy-Acetylene torch
Reply:Great job Duane. Man, if I lived in TX I'd be hangin around your shop all the time!"Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:To cool !!!!!!!!!!!!!!!!!!! LoL Great work !!!!!Miller 330 A/BP Bernard SS coolerMiller cst 250Miller Big Blue 251DCentury 210 Mig (first welder I bought)Hypertherm PowerMax 800Victor torch setRu Fong 31 MilAtlas lathe
Reply:Just thought I'd toss in - season #3 and still goin' strong . . .. . . even though I never did get to the black paint. MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:That would be nice here in Yuma, but I my tools would rust with all the extra humidity in the air.For now, I just suffer through the day, when it reaches 105* inside the garage, I shut it down.  Unless I have a major project to complete, then I just drink more water.I had forgotten you had done this.  Again, very nice fix.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:Very nice job.  Would a cold galvanized coating let it breathe any better than paint?  I know that when I need to buff soft paint in a hurry, I always break the skin with 1500 grit and bake it.  The sand scratches allow the solvents to come out quicker.  I have no clue how galvanizing works as far as heat retention.
Reply:nicely done duane but i almost choked when i seen that chuck key down in the ways!!1979 sa 200victor 100several bfh's several pitbulls (for holding down the floor)
Reply:That one impressed me....nice job!If you don't want to stand behind our Troops, feel free to stand in front of them.
Reply:[Account Abandoned 8/8/16 Please Do Not Attempt Contact Or Expect A Reply]. See you on YouTube! -ChuckE2009
Reply:Originally Posted by texasredneknicely done duane but i almost choked when i seen that chuck key down in the ways!!
Reply:i wouldnt be worried about hitting it more about strings grabbing it if it birds nests..i just have a fear of heavy objects getting slung out at me. When i was in school the idiot working behind me missed lefty loosey righty tighty day and put his three jaw in and "locked" the cams proceeded to polish his piece and sling his 80 pound chuck out of his and into my machine.....i got a new machine AND new under ware after that lol1979 sa 200victor 100several bfh's several pitbulls (for holding down the floor)
Reply:OK, I can see the birds nest thing being a potential issue.  I'll start hanging it off the ways behind the truck or tail stock to keep track of it. MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:While you're at it pull off that three jaw and learn the joys of chasing that last thou with a four for ****s and giggles.
Reply:I've looked for a reasonable 4-jaw from time to time and need to correct the current 3-jaw as I can only get it to within .002" run out.  The drive flange is spot on but the chuck itself is off. MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:In my severely limited experience with my lathe, I super hate 4 jaw chucks! Probably due to lack of experience and proper training...lolDave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:They're super handy for many tasks and not that hard to set up.  Just need a dial indicator and two chuck keys makes it even easier.  Can't tell you how many times I wish I had one.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Actually, two chuck keys would help now that you mention it....One of those simple things that should have been obvious - lol    Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:Originally Posted by duaneb55Dang MoonRise, I knew I should have tossed the whole thing in the dumpster!Grammatical and punctuation lesson 'duly noted'.First of all - not the same degree that you broke it down - everything you pointed out was considered leading up to the actual project.  OK, everything but the emissivity issue with regard to black painted-vs.-bare steel.A trip to TSC for additional fin material was considered however I elected to go with the 6 remaining pieces I had from a greater number for the fins as I was concerned about too much housing shrinkage if I included additional fins.  The same logic was my reason for the stitch welds in lieu of full length.  I thought about slowly finish welding the fins but chose not to out of concern for damaging the plastic stator slot insulators.Turns out after 2 hours of operaton Sunday afternoon in near 100°F the motor housing was barely warm to the touch so I'm going to call it good to go.  And even better yet once I give it a black paint job (thin) as I told RancherBill.As for the difference between the old aluminum and new CS housing, if the rotor could be supported and the stator prevented from rotated without it, the motor would still run.Thanks for the post.