Beginner project: FCAW vs brazing

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I'm completely new to metal joints outside of some lightweight soldering. I've landed on a project I'd really like to try: a bike trailer with suspension. Basically, it involves joints among and between EMT conduit and steel plate.Having read up a bit, I'm not sure how best to get started. As a beginner I'm not interested in sinking big wads of cash into nicer equipment unless I develop suitable skill and interest. For this relatively small job, I'm considering two approaches: (1) Brazing with a simple, MAPP-only torch, like this(2) Welding with a bargain basement FCAW unit, like thisI know I'm better off with a better brazing setup or a better welder, and that the listed options won't leave much flexibility for other projects down the line. But for testing the water on what seems like a pretty straightforward project, I'm trying to figure out whether either of these approaches would do the job. And yes, I'm aware of the safety concerns and precautions with EMT Thanks in advance for any input.
Reply:Originally Posted by GertaLivesI'm completely new to metal joints outside of some lightweight soldering. I've landed on a project I'd really like to try: a bike trailer with suspension. Basically, it involves joints among and between EMT conduit and steel plate.Having read up a bit, I'm not sure how best to get started. As a beginner I'm not interested in sinking big wads of cash into nicer equipment unless I develop suitable skill and interest. For this relatively small job, I'm considering two approaches: (1) Brazing with a simple, MAPP-only torch, like this(2) Welding with a bargain basement FCAW unit, like thisI know I'm better off with a better brazing setup or a better welder, and that the listed options won't leave much flexibility for other projects down the line. But for testing the water on what seems like a pretty straightforward project, I'm trying to figure out whether either of these approaches would do the job. And yes, I'm aware of the safety concerns and precautions with EMT Thanks in advance for any input.
Reply:The flux core might give you issues with welding EMT, being too hot.  I  am not sure about brazing with mapp only,  guess it depends on filler and your needs.  I can see frustration either way with EMT. If tubing was thicker the flux core would be a better choice than that mapp torch. With a better torch setup then brazing would be better for properly prepped emt
Reply:Originally Posted by tapwelderThe flux core might give you issues with welding EMT, being too hot.  I  am not sure about brazing with mapp only,  guess it depends on filler and your needs.  I can see frustration either way with EMT. If tubing was thicker the flux core would be a better choice than that mapp torch. With a better torch setup then brazing would be better for properly prepped emt
Reply:Thanks for the replies so far. The project is actually relatively light duty, such that I'm fairly sure I could stick to 1/8" for the plate components (or just work around by bolting thicker plate if needed). Much of the joining is EMT to EMT. So perhaps a low-end flux core welder would be enough.
Reply:Originally Posted by GertaLivesThanks for the replies so far. The project is actually relatively light duty, such that I'm fairly sure I could stick to 1/8" for the plate components (or just work around by bolting thicker plate if needed). Much of the joining is EMT to EMT. So perhaps a low-end flux core welder would be enough.
Reply:12 and 10 gauge mean 20 amp, not 15.  Would be much better off with a 20 amp circuit.  IMHO30+ yrs Army Infantry & Field Artillery, 25 yrs agoMiller 350LX Tig Runner TA 210, spool gunLincoln 250/250 IdealArcESAB PCM 500i PlasmaKazoo 30"  vert BSKazoo 9x16 horiz BSClausing 12x24 lathe20T Air Press
Reply:If you're looking to use flux core and emt in the same sentence, plus never having welded before, most likely you'll end up blowing that emt to heck and gone regardless of price, input voltage or name brand. A ceiling on the output power is going to be a tiny issue. Brazing would be my recommendation for a 1st, one and only project."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:With the limitations you've set, I'd go for brazing with silver solder. Pay alot of attention to correct joint prep, and adding gussets to the joints will increase their strength quite a bit. Might not be neccesary, but on the other hand overkill never hurts. Either way, as long as you do the prep work well I think a good torch and silver solder will make better joints than a cheap cr*p welder.
Reply:Originally Posted by storeman12 and 10 gauge mean 20 amp, not 15.  Would be much better off with a 20 amp circuit.  IMHO
Reply:Here would be a better way to have answer the question> are you planning to put a child in said trailer? If so then If they recommend that it be welded then that's what I would do for the safety reason. Second what type of surfaces are planning to ride on with said trailer. smooth asphalt trails or dirt off road type trails? Loads planning to be put in the trailer?Klutch 220si mig , stick, and dc tigHobart 140 AHP ALPHA 200X 2016Lotos LTP5000DSmith O/P
Reply:It would be cheaper to have someone else build it to your drawing. You'll have a lot of money invested by the time your done.
Reply:are you planning to put a child in said trailer? If so then If they recommend that it be welded then that's what I would do for the safety reason. Second what type of surfaces are planning to ride on with said trailer. smooth asphalt trails or dirt off road type trails?
Reply:The 90 amp flux core welder is the way to go. Make sure you put a box fan behind you to blow the fumes away from you.  Practice on a few pieces first to get a feel for it.  I have a 90 amp flux core welder and would have no trouble welding the emt. It is not as thin as you think it is. The only real problem is the galvanized coating. At worst you would need to sand off the area you want to weld to but I think you will be able to weld it without sanding it.  You do not want to breath the fumes so do it in a well ventilated area. Piece of cake.
Reply:1. Buy the Mapp Torch and give it a test run on some EMT. Even if it doesn't come out good the Mapp Torch is handy to have around for future projects.2.Buy the Fluxcore HF machine- buy some EMT and get to weldin' and then come ask questions.You'll spend days analyzing what you should buy  and we can spend your money easily 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:Take a look at what people are using for building bicycle frames, that would be relatively similar to the bike trailer. Countless bike frames have been brazed together over the last century and it's still done today. I've never heard of a single one welded with fluxcore (doesn't mean it doesn't exist though).
Reply:Originally Posted by SandyIf you're looking to use flux core and emt in the same sentence, plus never having welded before, most likely you'll end up blowing that emt to heck and gone regardless of price, input voltage or name brand. A ceiling on the output power is going to be a tiny issue. Brazing would be my recommendation for a 1st, one and only project.