Stick Welding Tips, Certification tests, machines, projects
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I've TIG welded using silica bronze before and keep some on the shelf, never heard of TIG brazing though.

I do refrigeration work as well so I have the 15% silver rods, not sure about flux coated ones.
if there's a welder, there's a way
olek
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weldin mike 27 wrote:
If you have a thick piece of c/i you can "butter" the edges of the weld zone with the nickel rods. This means pad welding over the top and then welding up with another, cheaper rod, like 7018.
Hello that is a good short resume . I did read preferably NiFe rods , may be for thermal expansion or suppleness characteristics.

NiFe used for less ductile weld.

I had to learn to weld enough to weld an iron frame with a partial crack ( drilled to release stress and stop it) . Crack from undue stress so I have some chances of success as this will be released.

I was told that in that case, if the crack did close jointive , just take an cast iron repair electrode 1/8 make a soft pre heat 100 celsius , and directly secure the edges of the crack after a good securing with dots of weld ( the name escapes me sorry)
Small 1/2 inches pinned (not so strong ) with a rounded tool. As soon you can put a finger go along ..as you said.

A friend did that a lot when repairing electtical machines or big ones on an atomic plant. The crack must be closed. And the heated zone reduced to the max.

As the weld go thru the iron so easily one have some penetration without opening the crack. In my case 3/8 thickness and I wanted to go thru with a X opening. No open root to limit deformation . One side , ( not long 1.5 ") open other side then test for cracks then other side then last bead (s)
Pianos , restorer and tuner
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olek
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MinnesotaDave wrote: For the OP, the two commonly available rods near me are nickel 99 and nickel 55, the Ferroweld rods listed below I have not seen in my local store[/i]
Dave chances are that your nickel 55 are bimetal NiFe.

Older welders did talk of iron electrodes but this did not work well.

Some iron will crack very easily when the weld cools peening limits that (with rounded tool), but root pass =no peening, say some instructions from elecrode makers.

Thin 2.5mm electrode for root. Minimal heat . If I had a too round bead I immediately cut it in the middle with a grinder , ( after peening)

We are supposed to see the peening traces so a too light hammer does not do ...but extra strong peening ...may be dangerous on thin grey iron. Less on spherical graphite iron wich is more robust.
Ductile iron can be peened with a pneumatic needle tool rounded I think.
Best
Last edited by olek on Wed Jun 14, 2017 9:43 pm, edited 2 times in total.
Pianos , restorer and tuner
Dedicated to learn welding since april
slowly learning ;) not complaining of doing beads and beads
pro inverter PROGYS 200 FV PFC CEL+tig lift
OA Oxyflam 1000 cutting and welding gas torch
bowleggid
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One of the most important things to consider when welding cast iron is weld prep. How you prepare the surface to be welded will have a great impact on weldability. Rule #1: Never touch cast iron with an abrasive. Most people break this rule, using a grinder to cut a nice groove in a cracked piece of cast iron (assuming a repair here.) All that does is smear graphite all over the surface to be welded, & the resulting weld looks like swiss cheese. Those same guys grind out the weld & do it again, & they get baby swiss cheese, & they do it again, & smaller holes, but still porous!
Simply use either a carbide burr (in a die grinder) to cut the cracked casting instead of abrading it. Or better yet -- if you know how to use a cutting electrode (gouge rod) -- gouge the crack to be welded. Now, don't use a carbon arc to gouge it, use a gouging electrode. That way you won't introduce more carbon to the casting, & you'll preheat it in the process.
Speaking of preheat, 400 deg. F is a good preheat for cast iron. Peening & annealing are also good practices, as mentioned in other responses.
Filler rod: Nickel-based alloy made for cast iron, as mentioned in other responses, or go here to see some excellent filler rods for cast iron (warning they're not cheap.) http://weldit.com/product_category/stic ... cast-iron/
What alloy (A/AAA or B/BBB) you need is based on whether you need the weld to be super strong, or super machinable. (the B's are the more machinable, the A's are stronger.)
olek
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bowleggid wrote:One of the most important things to consider when welding cast iron is weld prep. How you prepare the surface to be welded will have a great impact on weldability. Rule #1: Never touch cast iron with an abrasive. Most people break this rule, using a grinder to cut a nice groove in a cracked piece of cast iron (assuming a repair here.) All that does is smear graphite all over the surface to be welded, & the resulting weld looks like swiss cheese. Those same guys grind out the weld & do it again, & they get baby swiss cheese, & they do it again, & smaller holes, but still porous!
Simply use either a carbide burr (in a die grinder) to cut the cracked casting instead of abrading it. Or better yet -- if you know how to use a cutting electrode (gouge rod) -- gouge the crack to be welded. Now, don't use a carbon arc to gouge it, use a gouging electrode. That way you won't introduce more carbon to the casting, & you'll preheat it in the process.
Speaking of preheat, 400 deg. F is a good preheat for cast iron. Peening & annealing are also good practices, as mentioned in other responses.
Filler rod: Nickel-based alloy made for cast iron, as mentioned in other responses, or go here to see some excellent filler rods for cast iron (warning they're not cheap.) http://weldit.com/product_category/stic ... cast-iron/
What alloy (A/AAA or B/BBB) you need is based on whether you need the weld to be super strong, or super machinable. (the B's are the more machinable, the A's are stronger.)

I agree .yesterday I did make a few small welds on an iron balcony. a crack and securing the rake rail , I had to clean old rust and old paint down to bare metal plus a small v groove with carbide tool, any trace of rust and the weld was rejected.
pre heat 160 F just to avoid thermal shock (control with a a laser thermometer, but special pens are better).

the cooling is the difficult part, as keeping weld beads small. if you get too confident and make a long weld, snap ;)
cooling is very fast with the "cold regime', Esab even tell us to fasten it by blowing air around the weld, not on it.'.

with cracks secured by holes ,leaving them open is a good (security) option if possible.it is anyway very difficult to fill those holes withè

Wear gloves and protective face shield with carbide burrs they make projectiles that enter too deep in the flesh to be extracted easily sometime. And then, trouble, it get infectious soon, you may be sure your tetanus vaccine is up to date, and often open the flesh to allow the metal to be pushed out. An usb microscope or strong x30 60 magnifier with less help for that.
Don't ask me ..;)
Best regards
Pianos , restorer and tuner
Dedicated to learn welding since april
slowly learning ;) not complaining of doing beads and beads
pro inverter PROGYS 200 FV PFC CEL+tig lift
OA Oxyflam 1000 cutting and welding gas torch
olek
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Here is a link with iron electrodes and their use.

I did receive answers from the manager of that brand .

http://www.magmaweld.com/cast_iron.html

a training video from Castolin 224

All the electrodes for iron I have did look like those ones see below, English version

Used DCEN for "cold regime" from 60 to 80° celsius (140 -212 F )

DCEP if the object is cooked 500 600°celsius, (932 °F to 1112 F) then allowed to cool slowly (24 hours ideal)

https://youtu.be/FawQHeOoU6E
Pianos , restorer and tuner
Dedicated to learn welding since april
slowly learning ;) not complaining of doing beads and beads
pro inverter PROGYS 200 FV PFC CEL+tig lift
OA Oxyflam 1000 cutting and welding gas torch
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