Brazing, need advise to fill a ding

[TimBuck2]

I put a ding in the cylinder rod of my backhoe stabilizer leg. I filed the edges smooth and want to fill it and smooth it to keep it from ruining the seal.

I plan to fill it with Safety Silv 45 flux coated - this is what was commonly referred to as silver solder or silver braze.

I do a fair amount of stick and gas welding and OxAcy cutting but I have never used braze before, so am looking for some advice.

Melting point of the Safety Silv is 1225 F, using OxyAcy torch with "slightly reducing flame"

Do I do something special to get a reducing flame?

Any advise would be appreciated.

 

[Stimw]

Most cylinder rods are chrome plated, you will probably burn off the coating!
I would try regular lead solder and be careful not to get it too hot.

 

[CNC Dan]

Melting point of the Safety Silv is 1225 F, using OxyAcy torch with "slightly reducing flame"

Do I do something special to get a reducing flame?

Any advise would be appreciated.

More O2 than a neutral flame.

 

[dadster4]

At that temperature you may damage the chrome in a large area causing it to flake off and possibly reduce the hardness of the rod itself causing a weak point which will be apt to bend under load at a later time.

 

[Tractor Seabee]

Heed the advice above. Do not burn the chrome. I dinged a couple several years ago. Used a jewelers file and smoothed out the little ridge, used some 600 AL Oxide paper then some crocus cloth. No problem. The seal will only be damaged if there is a rough spot to catch on.

CNC Dan, back to welding school; a reducing flame better known as a carburizing flame is excess fuel gas not O2. That is the proper brazing flame, turn down O2 to get a yellow tinged flame (no smoke). Neutral flame is the steel welding flame or heating flame. Oxidizing flame is a harsh sounding flame with excess O2. Never used one of those.

Q/A welding of steel is fast becoming a lost art. I still like it; guess it is because that is what I first learned and am better at it. On thinner cross sections it is much faster and less cleaning.

Ron

 

[TimBuck2]

Thanks gents, glad I asked first!

 

[CNC Dan]

Heed the advice above. Do not burn the chrome. I dinged a couple several years ago. Used a jewelers file and smoothed out the little ridge, used some 600 AL Oxide paper then some crocus cloth. No problem. The seal will only be damaged if there is a rough spot to catch on.

CNC Dan, back to welding school; a reducing flame better known as a carburizing flame is excess fuel gas not O2. That is the proper brazing flame, turn down O2 to get a yellow tinged flame....


Ron

You are right. I was thinking of the reduction process, and got mixed up thinking of the flame itself, and the effect it has on the workpiece.

Thanks for the correction.

 

[Birdhunter1]

Take the hydraulic lines off. heat can cause pressure to build up in the encased oil and in severe cases the ends can pop off with body damaging force.

 

[ruffdog]

Mostly, I use a stone to remove dings on a cyl rod. The scratches left by a file could tear up a seal, especially when under pressure.

 

[Valbird]

Do I do something special to get a reducing flame?

More O2 than a neutral flame.

That would be an oxidizing flame. A reducing flame has less O2 than stoichiometric.

A slightly reducing or carburizing flame is preferred for most welding because an oxidizing flame tends to oxidize the weld material due to the high temperatures and the excess oxygen in the flame.

 

[CNC Dan]

. A reducing flame has less O2 than stoichiometric.

A slightly reducing or carburizing flame is preferred for most welding because an oxidizing flame tends to oxidize the weld material due to the high temperatures and the excess oxygen in the flame.

You are right. I was corrected in an earlier post by someone else as well.

 

[dntfxr]

I wonder if JB weld or some other epoxy would work if it would adhere?

 

[flyerdan]

I wouldn't worry about filling it, just dressing it down so that no sharps were cutting the seal. It's not like there will be any leakage, just whatever minute amount of fluid gets scuppered out in the crater. A bigger concern would be the possibility of rust forming in the breached chrome plating. Maybe cleaning with acetone and a stiff brush, like a trimmed back toothbrush would be sufficient for epoxy filler.

 

[jimmysisson]

Or leave the leg up so the ding is inside. No rust that way.

Jim