Brazing Guide

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Originally Posted by cold_ice

This is flaring:

[img]http://www.extremecooling.net/pics/1/1/werkzeug/10.jpg/img]

[img]http://www.extremecooling.net/pics/1/1/werkzeug/12.jpg/img]

This is swaging (with a punch swag tool)

[img]http://www.extremecooling.net/pics/1/1/werkzeug/20.jpg/img]

[img]http://www.extremecooling.net/pics/1/1/werkzeug/23.jpg/img]

Your second pic looks like a swagged pipe to me, you can stick another pipe with the same diameter into it.

Hope this helps you

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ok yah i have the first tool, it says flaring tool on the box, so it must make flares :P

do i need the second tool at all? or can i get by with just the first for joining tubing?

Make a pic from your flaring tool with the accessories, than I can say more about it. But normally you only can make flares with it.

ok, will do soon

do i need to get a swag tool?

You don't need it, but it's good to have one. A punch swag tool costs about 10$
I should look like this:
http://www.extremecooling.net/pics/1/1/werkzeug/19.jpg

guys i have a little problem with MAPP, it cannot make tubes red... :mad:

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Originally Posted by Malachia

guys i have a little problem with MAPP, it cannot make tubes red... :mad:

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hold it close to the tubing, and heat up the tubing for like 20-30 seconds

Quote:

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Originally Posted by blinky

hold it close to the tubing, and heat up the tubing for like 20-30 seconds

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hem...heat up??? sorry english is not my best subject :p:

[italian help mode ON]
scaldare intorno al tubo, qui c'e' un altra brazing guide: http://www.jwharris.com/jwref/procs/
[italian help mode OFF]
if you need help my friend, you have only to call me.

Quote:

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Originally Posted by Dimas

[italian help mode ON]
scaldare intorno al tubo, qui c'e' un altra brazing guide: http://www.jwharris.com/jwref/procs/
[italian help mode OFF]
if you need help my friend, you have only to call me.

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:p:

Mapp vs. Propane is like night and day. I can't imagine O/A.

Mapp should do just fine from my experiance so far, I heated up an entire 3/8" to 1/4" brass flare union in very little time. I don't see the need for an O/A other then convienance.

I mean most of us are building DIY systems because we don't want to shell $500-800 on a vapochill/prommie. So a $200-600+ torch is usually out of the question. Guess I'll have to put up a mapp video one day.

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Originally Posted by Newb101

Mapp vs. Propane is like night and day. I can't imagine O/A.

Mapp should do just fine from my experiance so far, I heated up an entire 3/8" to 1/4" brass flare union in very little time. I don't see the need for an O/A other then convienance.

I mean most of us are building DIY systems because we don't want to shell $500-800 on a vapochill/prommie. So a $200-600+ torch is usually out of the question. Guess I'll have to put up a mapp video one day.

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i will built a statua (hem....things like the liberty one in new york :D) for you
:p:

i have a question.....dont laugh! - well not yet... :p:

is it possible that a better connection can be made if you had one part cooled and the other end hot?
you see in some manufacturing processes, they heat up one part of metal (so it expands) and have another peoce of metal (whic is cold and so contracts)
when they attach the ends together (e.g in railway wheels, the axle is cooled and the wheel is heated so when they put the two togethwr, they form a very tight fit)
so my question is - can this thing be done or applied to brazing of copper pipes?

and so get better connestions and less chance of leaks :stick:

now you can laugh :ROTF:

Quote:

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Originally Posted by bxa121

i have a question.....dont laugh! - well not yet... :p:

is it possible that a better connection can be made if you had one part cooled and the other end hot?
you see in some manufacturing processes, they heat up one part of metal (so it expands) and have another peoce of metal (whic is cold and so contracts)
when they attach the ends together (e.g in railway wheels, the axle is cooled and the wheel is heated so when they put the two togethwr, they form a very tight fit)
so my question is - can this thing be done or applied to brazing of copper pipes?

and so get better connestions and less chance of leaks :stick:

now you can laugh :ROTF:

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Thats a good question why would we laugh? I don't know the answer though sorry

i dunno, i guess i must have missed something glaringly obvious..
anyways i have another question...
copper is a good conductor right?
so why are we using it on the suction line?
wouldnt it be more appripriate to use a material that was less conductive (has to be brazable of course)
and if we had less surface contact with the insulator then there would be less heast loss through the insulator.
but im not sure,
if you have air in the spaces then you get water and eventually corrosion and stuff.. i dunno, just thinking...

Quote:

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Originally Posted by bxa121

i dunno, i guess i must have missed something glaringly obvious..
anyways i have another question...
copper is a good conductor right?
so why are we using it on the suction line?
wouldnt it be more appripriate to use a material that was less conductive (has to be brazable of course)

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Doesn't really matter. In series, you add thermal resistance. Theres no limit on how high you can get it by just adding more. So instead of looking at exotic and expensive materials with tiny increases in resistance, you can just choose the correct amount of insulation.

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and if we had less surface contact with the insulator then there would be less heast loss through the insulator.
but im not sure,
if you have air in the spaces then you get water and eventually corrosion and stuff.. i dunno, just thinking...

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Its really just the thickness that counts, not the surface area. The surface is all at room temp, so theres almost no convection anyway. At least not if the insulation is good enough anyway.

Where can a good Oxy/Acetylene setup be purchased and how much do they cost?

My Oxy/Acet Harris torch.
http://www.snt-systems.com/tommy/torch1.jpg

Here is one of my Brazes with 15% silver rod's
http://www.snt-systems.com/tommy/braze.jpg

And here is a nother braze.
http://www.snt-systems.com/tommy/braze2.jpg

Here is a full on flux free copper to copper braze that i did a few night's ago.
http://www.snt-systems.com/tommy/copperbraze.jpg


My torch was over $1000 with all the tip's and the cutting outfit, my oxy/fuel reg's were $200 USD a piece and all my tank's (4 acet 4 Oxy) i have about $500 in them. BUT u can get a good mickey mouse setup for about $300.

Quote:

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Originally Posted by KaptCrunch

should have anti-backfire valves on both lines(Reverse Flow Check Valves)

at the handle connection

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With any setup it's better to have the flash guard's on the low side of the regulator....atleast that's what my book,and they told me for the past 6 year's while welding with Oxy/Acet Oxy/fuel system's and such.

Quote:

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Originally Posted by bxa121

i have a question.....dont laugh! - well not yet... :p:

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In response to your question after that (didn't want to add the big quote), I don't know how you'd manage to keep one of the pipes cold inside the joint during brazing. In order to make a fit you could do that, but I'd rather grind the diameter down slightly. A fit that tight might not fill properly. But if not, you can heat up the outer pipe and when hot insert the other tube.

sell that might work for a decent connection but prolly wont hold anything near the pressure we are using. btw oxy-mapp is realy good. could i use a oxy-accetylene torch head on my mapp and oxy bottles? i dont see a problem seing as the misture is correct, iam just maing sure :D

A good rule of thumb is 1/4". Thats the minimum length of tubing you should ever braze inside the connection. If you've got a quarter of an inch, it'll hold. If you can't get at least a quarter... then I wouldn't use it in a refrigeration system.

Quote:

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Originally Posted by JSU

sell that might work for a decent connection but prolly wont hold anything near the pressure we are using. btw oxy-mapp is realy good. could i use a oxy-accetylene torch head on my mapp and oxy bottles? i dont see a problem seing as the misture is correct, iam just maing sure :D

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If it will fit then yes u can..Problem with MAPP Gas is u dont get verry much of it, for about $300 u can get a good Mickey Mouse Oxy/Accetylene cutting/Brazing setup and u wont have the need to preheat your evap's on a propain hot plate any more as the accetylene is far hotter then MAPP

mapp-oxy is within 300 degrees F of oxy-accetylene

http://bernzomatic.com/bernzomatic/c...parisons.jhtml

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Originally Posted by BB mods's

If it will fit then yes u can..Problem with MAPP Gas is u dont get verry much of it, for about $300 u can get a good Mickey Mouse Oxy/Accetylene cutting/Brazing setup and u wont have the need to preheat your evap's on a propain hot plate any more as the accetylene is far hotter then MAPP

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my mapp bottle has lasted me ~6 months, theres a LOT in each bottle