Kevin

Steel and aluminum boatbuilding. See: "Boatbuilding Methods", in left-hand column of the Home page, for information about alloys.

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leakcheck
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Kevin

Post by leakcheck »

Can I braze Stainless with Mapp gas ??

Steve

Kevin Morin
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Mapp Gas Brazing

Post by Kevin Morin »

leakcheck, YES.

I'm not familiar with brazing SS as a regular practice, I've used silver (alloy) rod to braze or 'solder' SS. This is called silver soldering in my area, but given the temperatures are usually nearing 5.5 or 6k deg F for acetylene I'd say we were 'brazing'.

Mapp is almost as hot as acetylene 5k +F (I seem to recall but don't claim that is accurate) burned with O2, so it will depend on the brazing rod alloy, the flux, and SS alloy and section of material if you're hot enough to get the fusion needed.

If the SS is thin enough so the section heats enough to flow filler rod and flow the surface of the parent metal, any gas will do the trick.

I don't see why Mapp gas wouldn't work but we don't buy it in my neck of the woods, so I can't say for a fact from experience. All the numbers here are just my recall- not facts, but the close heat of these gases mean they're about the same, in some tips for gas welding/brazing you'd be mixed with air, not O2, but the stuff is still plenty hot for the job.

Cheers,
Kevin Morin

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leakcheck
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Post by leakcheck »

Thanks Kevin,

I am thinking of redesigning the chicken grill that I bring to the Glen-L gathering. I have extruded flattened stainless (I don't know what grade), and I want to solder/weld/braze stainless angle iron to it as a frame for flipping the chicken...My brother has a MIG? machine with a wire feed? and if I can find the right kind of wire for him to use, and the right flux (if you have to use flux) I will bring it down to him and have him do it.

He is not a welder...just has some toys

Steve

Kevin Morin
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MIG and SS

Post by Kevin Morin »

leakcheck,

I'd look at the MIG system to learn the roll size-hoping to buy as little SS welding wire as possible since you're only proposing using a few feet of wire at most! Cabinet mounted rolls for 'push' only systems use either a 15 lb roll 6-8" diameter or a 40lb roll 10" diameter.

Pistol style guns that have the wire roll mounted behind your wrist above the pistol grip will take a one lb. roll.

If the material you're MIG tacking/welding is all SS the MIG system will work fine. Just make sure you take the time to adjust wire speed and heat before you weld on your SS BBQ tool or you'll end up with bird droppings instead of welds.

A small 'double dime' tack or even a triple dime on both sides of the rods seems like the welds will hold up to cooking!

I'd need to know the machine and feeder, cross section of all the metal and the alloys to be more specific.

Round section bars to flat section angle or bar is not a solder/braze type joint. If you ground/sanded/filed a flat spot on each bar end so they had a contact surface to the flat surface of the new frame then soldering/brazing will work fine. If there is a natural 'gap' formed by the round curving off the flat -weld.

Cheers,
Kevin Morin

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leakcheck
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Post by leakcheck »

Kevin,

Thanks !

I will try to get more specific information in a couple of days. I think I will be seeing him on the 4th.

Steve

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leakcheck
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Post by leakcheck »

Kevin,

Here is what I gathered (which isnt much)

It looks like a mungrel welder sold by Matco call a ToolTech TTMIG wire feed somthing or other with 220v.

I will be (he will be) welding 1" angle iron 1/8" thick and one piece will have a hold drilled through it with solid 3/4 rod running through it and tacked or something.

What type of wire etc do I need : It is 304 stainless

Steve

Kevin Morin
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MIG Wire

Post by Kevin Morin »

leakcheck,
308L or 308si or 308lsi are the usual alloys for 304, and the size 0.030" is good because the welds will be small and you won't need the 0.035" heat and rate of deposit.

Not familiar with that MIG system or its open circuit voltage (weld starting power) so I can't recommend wire feed speeds, usually 150 to 200 inches per minute for these smaller wires, but I'd be stretching it to even estimate for a machine I've never seen. Depending on the gas cup size and distance to work, 12-15 cu/ft min of Argon should give these welds plenty of coverage, indoors, and I don't see any need to preheat 304.

Say, 80-90 amps and 20-22 volts, in that neighborhood, but each power supply has its own behavior so these are just generic, ballpark values.

sounds like drilling the 3/4" holes will be the majority of the work!

cheers,
Kevin Morin

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Post by Drew »

drilling thru stainless is always fun.. I recommend changing the angle of the drill if you can. most drills are 120 degrees included. For stainless 135 - 145 is a better angle for drilling. Also use plenty of coolant.. its gets hot quickly

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leakcheck
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Post by leakcheck »

Shoot dang ! You guys are back in that language that I don't understand !! :lol:

I will let me brother know what you said and see if we can figure it out...we will practice a little bit..but at 5 bucks a pound we won't be practicing too much ~ :roll:

Will let you know how it turns out ...

Steve

Thanks (I think...if you guys are fooling with me this will be good !! ...I think he has 75% argon and 25 percent somthing else that will kill ya...does that sound right ???)

I should do great with cutting the hole..hell, I'm a plumber...we can make swiss cheese out of a perfectly solid house !!

Steve

Kevin Morin
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Mixed Gas on SS MIG

Post by Kevin Morin »

leakcheck,

stainless steel work hardens pretty rapidly, so drilling can look like its moving along very well for a few fractions of an inch- then the material's surface gets 'worked' and hot, and you slow to a crawl and sharpen all the time. Just a word of caution, slow speed and lots of oil seems to be the best ??

mixed gas is fine, the mix is probably intended to improve penetration or reduce spatter in steel MIG but with that Argon component it should be fine with SS. I almost always work in aluminum so I use the term Argon for almost all cover gas- even when I should be more precise.

good luck and I hope the BBQ is a hit with all the work you're doing to the grill.

cheers,
Kevin Morin

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