Intro to Oxy-Acetylene Welding - Part 2

Summary

The video provides a step-by-step guide on using a filler rod for welding, demonstrating the process of joining two pieces of metal. It begins with the setup of the welding torch, tacking the metal pieces together, and explaining the 'circle dip' technique for adding filler material. The instructor emphasizes the importance of heat control, penetration, and safety precautions throughout. After testing the weld's strength with a hammer, adjustments are made to improve the technique. The video concludes with tips on purging the gas valves and offers practical advice for beginners, especially students learning welding basics.

Takeaways

• 💡 Fusion welding relies solely on melting metal together without extra material.
• 🛠️ Filler rod welding adds additional metal, enhancing strength and filling gaps.
• 🔥 Adjust the flame properly by managing acetylene and oxygen levels for efficient welding.
• ⚠️ Bend the filler rod to remember which end is cold and safe to handle.
• 🔄 The 'circle dip' technique involves creating a molten puddle, then adding filler material in a circular motion.
• 👓 Always wear gloves and safety glasses while welding to avoid burns and accidents.
• ❌ Insufficient heat and filler material can result in weak, surface-level welds with poor penetration.
• 🔧 Increasing heat and making wider, slower welds improves penetration and strength.
• 🔨 Test welds with a hammer to evaluate strength—more penetration creates stronger bonds.
• 🧯 After welding, turn off and purge the acetylene and oxygen valves to safely shut down the equipment.

Q & A

What is the main focus of this welding tutorial?

The main focus is demonstrating how to weld using a filler rod, in contrast to fusion welding where only the metal is melted together. This technique is used to fill gaps and add strength to the weld.

Why does the instructor find using a filler rod easier?

The instructor finds using a filler rod easier because it helps to get the puddle started and provides more control during the welding process.

What safety precaution does the instructor highlight regarding the filler rod?

The instructor emphasizes the importance of distinguishing between the cold and hot ends of the filler rod by adding a bend to one end, ensuring that the user knows which end is safe to handle.

What technique does the instructor use when welding with the filler rod?

The instructor uses a 'circle dip' technique, where they move the torch in a circular motion while intermittently dipping the filler rod into the molten puddle to add material as they progress.

Why does the instructor heat the metal before adding the filler rod?

The instructor heats the metal to ensure that it reaches the molten state before adding the filler rod. This guarantees that the metal is properly melting and not just the filler rod.

What does the instructor observe about the first weld after testing its strength?

The instructor observes that the first weld had very little penetration and was primarily a surface weld, which broke easily under minimal force.

How does the instructor improve the second weld?

The instructor increases the heat and makes wider, slower welds to ensure better penetration of the metal, resulting in a stronger weld.

What tool does the instructor use to test the weld strength, and what were the results?

The instructor uses an 8-pound sledgehammer to test the weld strength. The weld held up much better than the first attempt, showing increased strength even when hit from both sides.

What does the instructor recommend doing after finishing the welding process?

After finishing welding, the instructor recommends purging the valves, closing the acetylene and oxygen valves, and ensuring the equipment is safely turned off. They also advise cleaning up and practicing regularly.

What is the target audience for this welding tutorial?

The tutorial is intended for introductory-level students in grades 8 to 12, as specified by the instructor.

Outlines

00:00

🔥 Introduction to Using Filler Rod in Welding

This paragraph introduces the topic of using a filler rod for welding, as opposed to fusion welding. The speaker explains that adding filler metal can help fill gaps, provide additional strength, and make the process easier to control. The speaker starts by describing how to light the torch, adjust the flame, and perform a tack weld using a filler rod. They also emphasize heating the metal sufficiently before applying the filler, ensuring a good bond. The speaker gives tips like bending the filler rod to identify the hot and cold ends, ensuring safety while handling it during welding.

05:16

🔧 Demonstrating the Welding Process

In this section, the speaker walks through the actual welding process. They explain the technique of 'circle dip,' where the filler rod is dipped into the molten metal in a circular motion while moving forward. As they demonstrate, they adjust the acetylene and oxygen levels for optimal flame and review the results of the weld. After completing a weld, the speaker examines the quality, noting that while the weld appears good on the surface, it lacks proper penetration. This leads to the conclusion that more heat is needed for a stronger bond.

10:16

⚒️ Improving Weld Strength and Testing

The speaker decides to redo the weld, this time increasing the heat and widening the weld to improve metal penetration. They emphasize taking it slow to allow the metal to melt properly. After completing the weld, the speaker tests the strength by clamping the piece in a vise and striking it with a hammer. This time, the weld holds much better, though some bending occurs. The speaker decides to test further by using an 8-pound sledgehammer, which also shows that the weld is strong enough for practical purposes, though the metal does bend slightly.

🔌 Shutting Down and Recap of Welding

The final paragraph covers the process of safely shutting down the welding equipment. The speaker explains how to purge the valves, close the acetylene and oxygen regulators, and ensure that no gas remains in the system. After explaining the procedure for purging the valves, the speaker advises cleaning up the workspace and practicing welding regularly. In conclusion, the speaker clarifies that this approach is used in their welding classes for students in grades 8 to 12, and while it may not be industry standard, it works effectively at the introductory level.

Keywords

💡Filler rod

A filler rod is a piece of metal used in welding to add material to the joint being welded. In the video, the instructor uses a filler rod to fill gaps between two pieces of metal and add strength to the weld. The rod melts into the molten puddle of the metal, providing additional material for a more secure bond.

💡Puddle

In welding, the puddle refers to the small pool of molten metal created by heating the metal surfaces. The puddle is crucial in ensuring a good bond between the pieces being welded. The instructor emphasizes controlling the puddle before adding filler material, ensuring the metal melts properly to create a strong weld.

💡Tack weld

A tack weld is a small weld used to temporarily hold pieces of metal together before the final weld is applied. The instructor demonstrates using tack welds at the beginning and end of the joint to stabilize the metal pieces and prevent expansion or contraction during the main welding process.

💡Penetration

Penetration refers to how deeply the weld melts into the base metal, ensuring the weld is strong and secure. In the video, the instructor notes that the first weld had poor penetration, meaning it did not bond deeply enough into the metal, causing the weld to break easily under stress.

💡Acetylene

Acetylene is a highly flammable gas commonly used in oxy-fuel welding for creating the high temperatures needed to melt metals. In the video, the instructor carefully adjusts the acetylene to create the correct flame for welding, emphasizing safety and control to avoid accidents like flashbacks.

💡Oxygen

Oxygen is used in combination with acetylene in welding to intensify the flame's heat, allowing the metal to melt. The instructor adjusts the oxygen to achieve a properly feathered flame with a distinct cone, necessary for efficient and controlled welding. It’s essential to balance oxygen levels with acetylene to maintain safety and effectiveness.

💡Circular motion

The circular motion refers to the technique of moving the welding torch in small circles while welding. The instructor uses this motion to control the heat and ensure even distribution of the molten puddle. The 'circle dip' technique helps maintain a consistent flow of filler material into the weld for a smooth, strong joint.

💡Safety glasses

Safety glasses are essential protective gear for shielding the eyes from harmful sparks, heat, and debris during welding. In the video, the instructor stresses the importance of wearing safety glasses, especially when striking the hot metal with a hammer to test the weld's strength, preventing injury from potential flying fragments.

💡Hammer test

The hammer test is a practical method for checking the strength and integrity of a weld by hitting it with a hammer. The instructor uses this test to demonstrate how the weld holds up under force. Initially, the weld breaks easily due to poor penetration, prompting adjustments in the welding process for a stronger result.

💡Flashback

Flashback occurs when the flame moves back into the torch, which can cause an explosion or damage to the equipment. The instructor advises maintaining a proper distance between the flame, filler rod, and metal to avoid flashbacks, ensuring a safe welding process. Flashbacks can occur if the torch’s pressure settings are incorrect.

Highlights

Introduction of filler rod welding, adding metal for more strength and gap filling compared to fusion welding.

Explaining the technique of starting the puddle before adding filler material to ensure proper melting of the base metal.

Instructor demonstrates tack welding with the filler rod, explaining the importance of preheating before applying the rod.

Instructor explains the use of a bent filler rod to differentiate between the cold and hot ends, emphasizing safety.

Describing the 'circle dip' method used during the welding process for controlled application of the filler rod.

Detailed explanation of flame adjustment: balancing acetylene and oxygen for optimal flame control and metal heating.

Initial weld inspection reveals a surface weld with insufficient penetration, requiring increased heat and gap adjustment.

Discussion on adjusting technique for better weld strength, including increasing heat and using larger welds for deeper penetration.

Reminder about adjusting grip on the filler rod to prevent fingers from getting too close to hot metal.

Weld inspection shows improved penetration but still not optimal strength, prompting further adjustments.

Demonstrating a stress test with a hammer, revealing a stronger weld but still highlighting areas for improvement.

Final stress test with an 8-pound sledgehammer, showing the weld holding well under increased force, though slightly bending.

Step-by-step process for safely shutting down the welding setup, including purging acetylene and oxygen valves.

Instructor's final advice: clean up the workspace and practice welding regularly for skill improvement.

Instructor clarifies that the techniques shown are for introductory level grades 8-12 and may not match industry standards.

Transcripts

[Music]

[Music]

the next forum of Walden that we're

going to be doing is using filler rod to

weld these two together so the first one

was just fusion welding letting the

metal itself melt together this one

we're going to be adding a little bit of

metal to it to fill in our gaps maybe

give it a little bit more strength a

little bit more material in there I find

this is actually easier to get my puddle

started at in control let's do this so

once again light your torch just a

little bit I want a nice little flame

I'm going to increase the pressure till

it's feathered again

add my oxygen I'm gonna do my tack weld

with my filler rod by heating the two up

together get it almost a puddle I like

to get this nice and hot before just

sticking the coal rod on top of there

just a quick tack I do the same thing to

the other end before it expands or

contracts so evenly between the two

pieces you know it's getting kind of hot

they can tell us about to the molten

long gonna throw a little bit of filler

rod in there just enough to hold it

together this one's not for strength now

I'm ready to run might be here now then

so just quickly before I do this my

filler rod here I'm just using a very

thin one I've got two ends to this one

here and one here if you notice I've

added a bend to it I do that so I

remember which is the cold end and which

is the hot end so my cold ends so I

always know that if I grab here I'm

gonna be mostly safe unless this thing

is only of three inches long and this

end I'm gonna assume that it's hot

don't go touch it don't go lick it

please all right let's get back to

welding I'm gonna be wearing my gloves

I'm gonna be holding it like this with

my torch I'm probably gonna be doing a

very small circular motion and dipping

this into the puddle kind of as I go

forward so you'll see me circle dip

circle dip circle dip circle dip all the

way along where I want my weld to be

light it increase your acetylene until

it's feathered that's black smoke goes

away increase your oxygen until you have

that nice little cone and that's well

heat this up until it gets molten and

then we're gonna start adding our filler

material so I want to get that puddle

started before I add the filler material

cuz I really want to make sure that the

metal is melting not just my rod here we

go

puddles starting I'm going to do circle

dip circle dip circle and dip I get a

little bit more of a puddle going there

and just kind of circle dip maybe every

one or two circles let's go forward

I'm gonna stop there and we can take a

look at it

acetylene and then oxygen so if I look

closely at that I see I have a very nice

little I have a nice weld on top it's

gonna be strong enough I can flip it

over and see how the penetration is

again maybe not enough penetration I

think I'm gonna have to add more heat

let's continue this with some more heat

so again let's get our puddle started

I'm just gonna continue from where we

left off and remember that your filler

rod is gonna get shorter the longer you

well just be aware of where you're

holding it okay puddle has started you

need a couple circle dip Circle dip

Circle dip my filler rod sometimes goes

in between the flame in the metal that

kind of pre eats it and then lets it

drip into that little puddle there we go

much nicer I've increased the heat or it

I increase the pressure is working

lovely

that's settling off oxygen off it's not

a bad weld I'm a little bit rusty on

this I don't do this as often since I've

been using a MIG welder but I think this

is going to be strong enough let's clamp

into a vise and smack it with a hammer

and see how it holds up don't forget

your safety glasses and be careful you

don't hit your hand on this hot metal so

what does that tell me I look very

closely at it it broke off with very

little effort I got very little

penetration and it was mostly just a

surface weld so that tells me that I

need to have a bit more of a gap and add

more heat to get through a piece of

metal like that

let's do it again

start with my tax just to hold it in

place

enough get it hot before you add your

tax just to hold it together there's not

gonna be any real strength there

all right let's heat this thing up I

turned up the heat I'm going to add some

bigger welds I'm gonna go a little bit

wider and really try to penetrate this

metal

circle dip circle dip I'm gonna take my

time really get that metal melted

through there this time

careful how close you are so you don't

get any kind of dip or flashback adjust

your grip on your filler rod now and

then to make sure you're not getting too

close to the metal with your fingers now

nice and slow nice big wide here

settling then oxygen to turn it off wait

for that's a cool for just a moment and

let's flip it over

lovely so we have a lot more penetration

coming through this one still not quite

enough to make it extremely strong but

it might hold up better than the last

one so if you look closely at that

there's a little bit more penetration

than there was before you can see it

more down on this side here not so much

this ones where we ended we have the

whole metal going really really hot do

not touch this this will blister a lot

let's put this over and take a quick

look at that that's a decent weld you

can tell that it's really curved into

the metal a little bit more kind of like

this like a scoop I could go over it

again if I wanted and add a bead on top

of that but let's see how strong this

one is it's clamped in let's grab our

hammer that's much stronger than the

first one let's hit it from both sides

so depending on its use this would be a

fine weld I think we need to go get a

bigger hammer so we got an 8 pound

sledge let's try that one now it is

bending a little bit but the weld is

still holding let's get a closer look at

that

not too bad it's still holding up pretty

good now just for fun let's just break

it so once we are done welding we need

to turn off this whole setup I'm going

to start by purging the valves so it's a

purge the valves I'm gonna close my

acetylene first close that till it's

tight I'm gonna roll back my regulator

the - or in this case counterclockwise

open my acetylene to make sure all the

gas is left the acetylene valve empty if

you look close that here it'll be

reading zero next oxygen turn it off all

the way clockwise good we want to get

this to be empty reading zero I'm going

to turn my valve back all the way

counterclockwise open my valve

and this should be going down to nothing

turn it off

wrap it up for everybody else put your

striker away clean up your mess and

practice everyday

so just to recap this is how I do it

with my classes this is not necessarily

industry standard but this is what works

well for us at a complete introductory

level from grades 8 to 12 have an

awesome day