welding question: fill in the gap?

[mhorowit]

Please see attached sketch.
Using Oxyacetylene, how do I get the base molten without burning the two
pieces that form the 1/8" gap? Are "chill bars" the only choice? MikeH

[Howard Wilson]

Re: welding question: fill in the gap?

Timing. Flicker over flicker back until all pieces are ready.

[mhorowit]

Re: welding question: fill in the gap?

Timing. Flicker over flicker back until all pieces are ready.

Howard - in order to heat up the base (flame coming from the top, thru the gap) I gotta heat up the edges; flicker between what? - MikeH

[Howard Wilson]

Re: welding question: fill in the gap?

The pic looked like you could do some pre heat or flame tip heating from the bottom??? I guess my question after rereading your example would be; do you need the gap? Not sure about the application here

[tawadc95]

Re: welding question: fill in the gap?

observe the color of the metal.
if one part is getting red and another staying dark move the flame over to the dark part.
when they turn red make sure they are the same red,not one piece cherry and the other turning white.
it is all about heat control and bringing the pieces up to heat together.
thickest piece gets the direct heat first as I am sure you know.
flicker means to move the torch around and warm it up in an even manner.....ie. one area gets the cone and as it heats move it to the edge of the flame and let another area have the cone.
patience,heat control and practice on a dummy setup of the same situation

[mhorowit]

Re: welding question: fill in the gap?

wouldn't be able to apply heat from the bottom. I'm trying to duplicate the technique I'd need for welding the trailing edge of an external sleeve applied to a landing gear strut OR the weld I'd have to do when repairing tubing by internal sleeve. All require puddling the innermost piece of metal so that it flows into the external pieces; unfortunately, heating the inner piece requires heating the outer pieces and they tend to melt quicker. - MikeH

[Acroeric]

Re: welding question: fill in the gap?

Mike- If it was done before you'll eventually be able to do it too. It took me 2 months of scrap metal welding before I'd weld on my clipwing.

Joints like that require a good eye on both pieces-especially if one is of a thinner wall, also- welding rod placement helps with the amount of "fill" you get and can even help shield some of the flame.

[N96337]

Re: welding question: fill in the gap?

Mike, Eric's right..it just takes practice practice practice...... I've also found that alot of people tend to have way too much heat when they're welding. It's not a speedy process to get everything up to temp, but once there, it doesn't take as much heat to keep it all at the right temp... practice practice practice....
JH

[Guest]

Re: welding question: fill in the gap?

Hi Mike and all,

Mike checkout the AW1A torch on this site;

http://www.smithequipment.com/products/pdfpages/page18.pdf

I have had best luck with that torch, probably any small torch like it will work the same.

The tips are at;

http://www.smithequipment.com/products/pdfpages/page44.pdf

Maybe you have this already.

Dave

[Ragwing nut]

Re: welding question: fill in the gap?

What size tip are you using and what thickess metal?

Mike

[mhorowit]

Re: welding question: fill in the gap?

What size tip are you using and what thickess metal?

Mike

the hole size is .003 and the 4130 mics slightly over .004. I'm running 2.5 psi on both gasses, neutral flame(slight feather) and at the lower end of the range (small flame) - MikeH

[Guest]

Re: welding question: fill in the gap?

Is there a decimal off? .004 metal? that's tin foil

What torch type/model do you have?

[Ragwing nut]

Re: welding question: fill in the gap?

I think you missed your decimal place. On the tip should be a number that denotes tip size. "00", "0", "1", "2", etc. Would have to look up what it translates in diameter to but for welding typical .035 or .040 4130, you should be using nothing bigger than a "1", more often than not a "0".

A trick I use for welding inner sleeves is the outer tube has a 1/4 inch hole drilled in it or what ever the required diameter is suppose to be. I drill an inner hole 1/8 inch to start the rosette. Otherwise it is very hard to get the inner tube molten first because it is acting as a shield diverting the heat to the edges of the outer tube. With the hole, it allows the heat to pass into the tube and brings the inner tube to a molten state much faster.


Mike

[mhorowit]

Re: welding question: fill in the gap?

Is there a decimal off? .004 metal? that's tin foil

What torch type/model do you have?

Yes, the decimal is off. .040
It's an old smith like yours - Mike

[mhorowit]

Re: welding question: fill in the gap?

I think you missed your decimal place. On the tip should be a number that denotes tip size. "00", "0", "1", "2", etc. Would have to look up what it translates in diameter to but for welding typical .035 or .040 4130, you should be using nothing bigger than a "1", more often than not a "0".

A trick I use for welding inner sleeves is the outer tube has a 1/4 inch hole drilled in it or what ever the required diameter is suppose to be. I drill an inner hole 1/8 inch to start the rosette. Otherwise it is very hard to get the inner tube molten first because it is acting as a shield diverting the heat to the edges of the outer tube. With the hole, it allows the heat to pass into the tube and brings the inner tube to a molten state much faster.


Mike

Yes I missed a decimal point. .040 is closer.
I didn't use a tip number because it varies with manufacturer ; I can give you the Smith tip number but I thought more info would be conveyed by providing the blowhole size. Wrong?

I know that Rosette trick and it's first cousin to this problem - the outer hole gets larger and larger until the inner tube decides to puddle. Same problem. fortunately, a rosette hole of 1/4" isn't a problem. Now, if someone were to say "let the outer sleeve burn back", problem would be solved. Also, if someone were to say 'make two parallel beads' life would be good, but until that time, I gotta assume this weld is a single bead which incorporates the inner sleeve and both edges of the split outer sleeve. Correct me if I"m wrong, please - MikeH