Quote:
Originally Posted by blinky
around 6h at full "speed" !!!
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Quote:
Originally Posted by blinky
around 6h at full "speed" !!!
Does anyone in here Nitro Purge while they braze?
Quote:
Originally Posted by blinky
Iv brazed and welded with allmost every thing there is and u dont have enuff Mapp fuel in each bottle to last u 6month's..6 hour's is clsoer to the limit on the tiny bottle's.
Yes i have used a nitrogen purge when iv brazed and welded,work's good to help clear out all the extra gases in the system.
Quote:
Originally Posted by JSU
Yea...but when it comes to holding a far hotter flam longer and applying the heat faster Oxy/acet work's much MUCH better.I have my shop and year's of service to show for it...that and u go in the hole buying little bottles of MAPP gas..the cost of a good oxy/Acet setup is well worth it.Now if u could get Mapp in a 60NL or something then yea,Mapp would be good.Got to love teh Tripple bonded carbon that is Acet :D
Was curious if anyone did. Was going to reccommend that it be done. It prevents oxidation inside the tubing. Meaning no flaky stuff clogging up your lines and messing up your compressor, and contaminating your oil and refrigerant. :)Quote:
Originally Posted by BB mods's
You are correct Sir.It also help's to prevent a flash back if u use a flamable gas like r-290 in your system and have to fix a part of it.
One of these days at work I'm gonna get out the boroscope and we're (engineers and I) are going to inspect just how well Nitro Purging works, and just how much flow we need. Alot of people that do the brazing don't think it works. Should help to prove it to them.
You dont need alot of flow. For these small systems 10cfm should be enough. Or a couple Water Collum Inches
I just noticed that the video still was at my very old webspace, to bad, i didn't saved it and my harddrives crashed.
I will record a new tomorrow, if there are no more objections of the used method.
To Braze Stainless steel to copper, do braze like normal except use the high silver rods?Quote:
Originally Posted by Sidewinder
Is there any other reccomendations?
Realy only want to heat up the copper when doing this. However what they say and what accually works isn't alway the same thing.
For copper to any other metal, besides Al. I've found the flux coated rods to work the best.
Ya,
Thats the way I was going to go. I'll be brazing SS Parker fittings to copper in the near future, so was going to use the silver blue rods that came with the torch. I believe it'll work fine.
RussC
Quote:
Originally Posted by Redwolf
The video was about how to light the torch.Quote:
Originally Posted by johann
I open oxigen first, add acetylene/ethyne and then light it.
Stainless steel connections are simple. Flux the joint real well even on the outside to prevent it from carbonizing on the outside (it looks better). Coat the silver rod with flux (its cheaper this way since you don't have to buy flux coated garbage.)
Heat the copper and apply the filler while applying heat to the steel. You do actually want the steel to glow red, but be careful because it will heat up REALLY fast. Keep that heat off of the steel until you're ready with your filler. Apply quickly, draw it in, and take the heat away when filled. Shouldn't take but a second to fill it since I gather its a small joint, right?
As for lighting the torch... that should be obvious. Gas, then oxy. Of course, if you want some fire crackers, turn the gas and oxy on then light :p POP! hehehe
why don't people just read the manual of their torch how to light it? :) In europe most torches should be lit like sidewinder does it, first oxy then fuel. Why? well the torch design is different. these torches use the oxygen flow to suck out the fuel. "translated" from dutch we call it an Injector torch. Just make sure the fuel hose is pressurised when you open the fuel knob on the torch or you'll get oxy in the fuel hose.Quote:
Originally Posted by Stewie007
In the USA you apperently work with a different design torch, that's all. Now nobody can argue about it anymore and we can all enjoy sidewinders new clip ;)
The evap brazing videos would be more than welcome too and glad you changed your mind :toast:Quote:
Originally Posted by Sidewinder
Well here in Portugal everybody lights the gas first then opens the Oxy
the only problem with that is you get that black carbon soot floating around. Once you "know" your torch you can just crack the o2 , then turn the gas on , then strike. No "floaties" in the air.Quote:
Originally Posted by Blaster
Yep. Acetylene tends to smoke alot on its own :)
Woah, took long time for me to understand your replys, my english gone really bad.
Manual? haha, i never had saw a manual for a torch ;)Quote:
Originally Posted by Unknown_road
You may be correct with different types, never thought about that.
Im thinking of writing a howto for building a cooling unit for a german forum, maybe i could make a few videos and pictures for this thread.Quote:
Originally Posted by LowRun
Well, years ago this also was the how to method in germany.Quote:
Originally Posted by Blaster
we learned at school to open up the acetylene and oxy at the same time,
little bit of acetylene and then light it up.
lighting the acetylene without oxygen can cause cancer in long period.
thats what they learned us at school:)
never had any problems with this method.
:)
After reading almost all 6 pages full of posts, some comments first:
I was taught to turn on acetylene first, light it (you do see soot coming out, that's why you point it away from you)
open up oxygen slowly and very carefully, the flame will get shorter and brighter, and hotter :P
fine tune the flame so you get only 3 and very distinctive flame parts, the cone, the hottest area, and the colder but somewhat brighter area.
I think all tourches should be the same, in the americas and europe, because you're using pressurized gas not an airbrush, so oxygen isn't needed to draw acetylene out. Having a mixture of acet. and oxy. in a closed chamber gives a higher chances of flash back pops resulting in dead flames.
still have some questions:
When purging with propane, do you light the outlet on fire or vent it; and how to know when to light it (if that's the case)
For brazing rods, is there a list of adhesive strength on copper to copper and on copper to steel?
Is a welding machine good for sealing 2 copper pipes?
maybe you think all torches should be the same but they aren't. the reason why some torches are designed to let the oxygen suck out the acethylene is because you can set the acethylene at a much lower pressure reducing the risk of something going wrong with it. every torch has a chamber in which acethylene and oxygen are mixed.
On my torch the oxygen valve has to be opened first too, and then Acethylen.
WOW... I went to use a bigger, meaner, stronger torch today... took me 30min to braze a desuperheater to the condensor :eek: lol the copper kept melting and steel n' copper doesn't heat up at the same rate...
Question:
What should I use as a heat shield when brazing the compressor?