Fixing hole in side of block

[joesmith123]

forget about the patch for now
instead get the heat on the cast and see if you can get a small pool of bronze to attach to it.

Bingo - you read my mind exactly, I was fixing to come and say those exact words, because


I have never gotten a weld to stick to anything before what I showed Yall this morning

Even that is an achievement for me

Of course it would be tricky to weld on cast iron, my instincts see it as a petrified metal, very stubborn to get anything to hold onto it

So yes, forget about the patch, hone in on what it will take to get cast iron to bond to bronze

Next experiment: Hit the iron skillet with regular propane torch, get the entire entity hot not just the welding area, then come in with the acetylene and hit it until it has that wet look like yall advised

Next experiment taking place early evening or evening if I have the energy

 

[joesmith123]

My only suggestion to OP would be to go on Welding Web and post this repair with questions about how to do it. I would also ask those guys if one of them is nearby and could help out or do it

Zero chance I would go anywhere outside of this forum

Are you reading these responses? They are busting at the seams with data. They even cater their answers to my newbie questions

No amount of money can i pay someone to teach me and answer my questions the way this forum does

I honestly believe the knowledge of this forum is better than all universities/schools combined

2 days ago I had no clue that bronze rods even existed, and now they got me sticking it to the patch and it won't even come off with a hammer, Unbelievable

And all yall saying I won't get the patch to stick, please keep saying it, I am only motivated when yall say "you can't do it"

 

[joesmith123]

You can not put enough flame to it to melt cast iron!

Yes I realized that now, I'm fixing to hit it with the acetylene until it gets that wet look

You need to take your pan and throw it on a BBQ grill on high for a min of 15 min.

Yes I am comprehending, I do have a BBQ grill to put it in and preheat it

Also your flame is not adjusted properly because you're leaving soot on the parts.

Hmm, it could be the impurities cooking that were not removed from the skillet when I hit it with grinding wheel

 

[fried1765]

Yes I realized that now, I'm fixing to hit it with the acetylene until it gets that wet look




Yes I am comprehending, I do have a BBQ grill to put it in and preheat it



Hmm, it could be the impurities cooking that were not removed from the skillet when I hit it with grinding wheel

Go for it Joe!
You will "figure it out".

 

[fried1765]

You can not put enough flame to it to melt cast iron!

You need to take your pan and throw it on a BBQ grill on high for a min of 15 min.
Your patch needs to fit into the hole ( like a plug not a patch) so not over it the cast.
You need plenty of flux and a good rod, heat both materials till the Brazing rod flows to it.
You can use mutiple passes to build the patch up and seal the hole.
Also your flame is not adjusted properly because you're leaving soot on the parts.

So,.......should the next step be to put the entire engine block on the grill for 15 minutes, and then braze the steel patch in the hole.
I just don't see that as being doable with the equipment that Joe has.!

 

[jaxs]

So,.......should the next step be to put the entire engine block on the grill for 15 minutes, and then braze the steel patch in the hole.
I just don't see that as being doable with the equipment that Joe has.!

If at first Joe doesn't succeed he'll "hit it",,,,,,,then,,,,"hit it" again until he figures it out.

 

[Lil Foot]

As others have said, not hot enough, marginally clean enough. (on 2nd attempt)
Preheat as others have said, (really hot) and use a much bigger tip (3 to 4 times the size pictured) and a correspondingly bigger flame.
Then you may have more success, but you will also find out why several have said you need bigger gas bottles.

 

[North Idaho Wolfman]

So,.......should the next step be to put the entire engine block on the grill for 15 minutes, and then braze the steel patch in the hole.
I just don't see that as being doable with the equipment that Joe has.!

Yes or a make shift brick oven.

 

[Russell King]

You could perhaps use a smaller piece of the cast iron to get it hot enough to melt the braze material. Then you will be able to see what it looks like at the different temperatures as it is heated and cool. Maybe the square you cut out or a quarter of it ?

 

[joesmith123]

Put skillet in BBQ grill heating it as I type this

Got the barbecue grill with a smaller tractor took off the legs of the barbecue grill, put the barbecue grill on cinder blocks and connect to the propane. Preheating now for 15 minutes.

Goal: Hit the cast iron with acetylene, melt the bronze into it successfully

I'll fix to try a nice circle bead emulating the patch job

Second attempt where we put the skillet in a barbecue grill and I preheated it to 400 for 15 minutes. Also, sprinkled flux on the right side of the skillet to try to understand what it does

More acetylene, more heat trying to bind the bronze to cast iron

Slowly increasing my heat input into the braze trying to understand the right amount of heat to give the cast iron to bind it to bronze

There was times when I saw the wet look, along the bottom of this attempt

My hesitation: I am nervous about hitting the cast iron too hard with he acetylene in fear of some kind of trouble, is my fear founded or unfounded?

Maybe: I should take cast iron skillet away from propane and grill and any dangers, put it on cinderblocks and just hit it with acetylene until I see the wet look, without bronze rod in left hand, focusing fully on just the torch and the cast iron, and if it turns to molten, it will just fall on dirt ground or cinderblocks

Now: leave skillet in oven for a bit, shut BBQ down, let it cool

Later: Hit the welds with hammers and chisels assessing their strengths, then make proper observations and readjust the plan

Check out what happened after I let it sit in oven at 400 degrees

Catastrophic damage to the test subject from too much heat

Got the bronze to successfully bind to the cast iron

Another look at the warped cast iron

 

[TerryKing]

Dear Joe, You get the PERSISTENCE award!! You also have built-in OPTIMISM. We are all learning a lot and not just Brazing...

Here's the Hat I've been wearing the past 10 years, starting at age 74. Wore two out. This version from 2 years ago as I was going to live in the Middle East for 2 years...

Best Regards! Terry

 

[fried1765]

Put skillet in BBQ grill heating it as I type this

View attachment 135877 View attachment 135878 View attachment 135879 View attachment 135880 View attachment 135881 View attachment 135882 View attachment 135883

Got the barbecue grill with a smaller tractor took off the legs of the barbecue grill, put the barbecue grill on cinder blocks and connect to the propane. Preheating now for 15 minutes.

Goal: Hit the cast iron with acetylene, melt the bronze into it successfully

I'll fix to try a nice circle bead emulating the patch job

View attachment 135889

Second attempt where we put the skillet in a barbecue grill and I preheated it to 400 for 15 minutes. Also, sprinkled flux on the right side of the skillet to try to understand what it does

More acetylene, more heat trying to bind the bronze to cast iron

Slowly increasing my heat input into the braze trying to understand the right amount of heat to give the cast iron to bind it to bronze

There was times when I saw the wet look, along the bottom of this attempt

My hesitation: I am nervous about hitting the cast iron too hard with he acetylene in fear of some kind of trouble, is my fear founded or unfounded?

Maybe: I should take cast iron skillet away from propane and grill and any dangers, put it on cinderblocks and just hit it with acetylene until I see the wet look, without bronze rod in left hand, focusing fully on just the torch and the cast iron, and if it turns to molten, it will just fall on dirt ground or cinderblocks

Now: leave skillet in oven for a bit, shut BBQ down, let it cool

Later: Hit the welds with hammers and chisels assessing their strengths, then make proper observations and readjust the plan

View attachment 135890

Check out what happened after I let it sit in oven at 400 degrees

Catastrophic damage to the test subject from too much heat

The end of this brazing attempt is approaching!

 

[Jim L.]

The tears start at the cuts made by the cutting wheel. Imagine adding heat to the pan as a thermal expansion of the entire pan. The sides of those cuts are moving away from each other, and the tension exceeds the strength of the metal.

Another approach might be to use an oversize patch, drill holes for mechanical fasteners such as bolts. Custom cut from gasket material to form a compression seal where the patch overlaps the block hole.

 

[joesmith123]

Another approach might be to use an oversize patch, drill holes for mechanical fasteners such as bolts. Custom cut from gasket material to form a compression seal where the patch overlaps the block hole.

I am with you and definitely comprehending what you are saying

I can go that route if this route does not work

I Like this route first since it is more permanent. But your route will also work if I cant get the braze to hold

Observations: notice how the bronze stuck permanently better on the side where i sprinkled the flux

the flux lowers the temperature required for the bond to form between the two entities

OK now that I can get the bronze to stick to the cast iron, do the mock patch on the broken skillet like Greenville and wolf said -

do not patch OVER the cast iron, cut the patch smaller than the hole and make it flush with the cast iron

 

[Jim L.]

It's called "pre-tin." Generous with flux to block oxygen. Get a layer of braze material on the cast iron. Then braze the patch to the cast iron.

 

[jaxs]

The end of this brazing attempt is approaching!

Not yet! You'll know it's getting close when Joe begins hitting it with his head. Right now Joe still has more optimism than a flea creeping up on an elephant with rape in mind.

 

[joesmith123]

Not yet! You'll know it's getting close when Joe begins hitting it with his head. Right now Joe still has more optimism than a flea creeping up on an elephant with rape in mind.

Definitely not over, still need to:

Successfully put a patch on the cast iron skillet that holds tight

I need to get more comfortable with the temperature, too cold and bronze won't stick, too hot and I will crack the entire block

Not brazing on the engine block until I can make bronze hold onto cast iron TIGHT without damaging the cast iron entity from too much heat

 

[North Idaho Wolfman]

The heating of the cast is not to get it to melt anything it gets it up to a temp that makes the added heat needed to get the bronze to flow less of a shock for the cast.
The reason the pan broke the way it did is because you introduced uneven stresses on it when you cut it.

One much more achievable simple result can be achieved by crafting a patch for the block out of mild steel and then use an epoxy like JB weld to bond the two together.
I fact you would need any thing else other than epoxy to fill the hole, because you could dam the back of the hole with tape.
You wouldn't be introducing any more stress to the block and you will be able to achieve a permanent patch, that will out live you or I.

If this was my project I would do just that and I know how to weld, and I know how hard it is to weld cast.

 

[Workerbee]

Joe, its not high heat that cracked your block. Its how you induced the crack in the way you left the grooves or cuts from your grinding wheel. Those are exactly like a crack and will extend by heat which causes expansion. Now try another skillet and drill a round hole in it. Heat that all you want and its not going anywhere.

 

[Lil Foot]

Joe, its not high heat that cracked your block. Its how you induced the crack in the way you left the grooves or cuts from your grinding wheel. Those are exactly like a crack and will extend by heat which causes expansion. Now try another skillet and drill a round hole in it. Heat that all you want and its not going anywhere.

I think you meant "Joe, its not high heat that cracked your cast iron skillet,"