Braze or solder broken cast iron plane sides?

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I only have one of the cheap gasless MIG welders (and a level of talent with it that needs a grinder and paint afterwards), so I assume trying that would be a really bad idea.
 
I'm sure someone on here, possibly now decamped to the a different place, used to regularly post work in progress photos which showed a no.4 with a brass repair plate screwed/riveted across a crack in the casting. It looked a bit Frankenstein, but was his goto plane.

Edit - here you go:

https://cdn.imagearchive.com/ukworkshop/data/attach/18/18169-Repaired-no.4.jpg
A forum search for "AndyT plane repair" turned this up.
 
Cast can be welded using a cast iron suitable rod on a stick welder mig welding on cast I have done but u have to control the cooling process with oxy acetylene to stop weld fracture far from easy to do
 
If it has sentimental reasons for keeping, I’d definitely leave it to a professional or you could end up with a piece of scrap
 
It may be possible to put brass dowel pins (nails) in to the plane and 'new' shaped side piece of steel /iron and join the scribed meeting edges using a thin line of metal weld type paste. Best not to do too much as it becomes what is or was not. Total restoration is not best. Flat planing would be OK. This is done on m/cycle side-valve heads. A honest repair.
Best wishes to all.
 
If you made the missing piece from brass too and then brazed it on it would show the old vs the new in an honest way rather than look like a crack full of braze. Would have a higher chance of success and look good too
 
especially when it comes to Tig which is a steep learning curve
The hardest thing about TIG is keeping the tungsten gap constant and feeding the filler rod in which is like a dipping motion, much easier if you have gas welding experience. TIG is the ultimate welding process, all positions, any direction and so easy to join thin gauge material to much heavier gauge so a process worth the practice. You also want HF start and cleanliness, acetone is a great cleaner for TIG welding and don't wear heavy welding gloves, just lightweight gloves and if using a watercooled torch then wrap the cables round your arm for added support.
 
I've been meaning to repair a cracked chipped off rear corner of a #5, by smoothing off the rough edge then adding some brass soldered on and then drill and tap some brass screws, then file off the head - all of which is a bit fiddle hence it still being on "round tuit" list - I'd be interested to see your repair.
 
I've got an old #4 1/2 hand plane that has some sentimental value and I'm trying to restore it to an at least reasonable aesthetic condition.

Some of the side is snapped off and long gone (see pic):

View attachment 135835

I've seen many brazed plane repairs over the years, but always using (what I assume is) brass rod; and I don't like the obvious colour difference. If I were to get some cast iron and machine it to an appropriate shape are there silver/grey brazing rods I could use with a MAPP torch, or would a "normal" plumbing solder be strong enough to hold a new part?
My brother, before he passed, was a reasonable welder and he managed to weld a broken cast iron coffee grinder handle back together using a technique he called sif bronze welding, or at least that’s what it sounded like. It was very successful and the grinder is in use to this day. Sorry, can’t ask him for any further details!!
 
You can weld cast iron, especially with modern techniques.
However, the old principles still apply - GENTLY heat the whole piece, weld and then ensure a SLOW controlled cooling. This used to be done by covering the welded piece in VERY hot sand and allowing it to cool as slowly as possible.
Cast iron is a crystalline material, easily subject to crack development under uneven thermal changes.
Brazing is easier because the heat required is less and the thermal stress is less - but visually - and for strength _ it is inferior.
It's why iron castings were buried in sand or hot earth, sometimes for years - to relieve stresses and allow the correct crystal structure to grow. A common practice for railway wheels and good quality lathe beds.
That's why it's best to get the weld done by someone with experience.
 
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I bought some (apparently appropriate) silver brazing rods, but like so many other projects I haven't had time to get back round to it yet. One day... one day :)
 
Broken planes used to be repaired by brazing.

The plane would be perfectly functional but you’d have a bronze coloured lined where the break happened.
 
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Broken planes used to be repaired by brazing.

The plane would be perfectly functional but you’d have a bronze coloured lined where the break happened.
That's ideally what I want to avoid - though I accept it may be easier said than done.
 
Grind it right down then put it on ebay as 'specialist super rare plane oddity' with a starting bid of £200. The plane collectors will go mental for it.
 
That's ideally what I want to avoid - though I accept it may be easier said than done.
That was done by time served welders, it’ll be strong and functional, you’ll have to turn the repaired side towards the wall if you want an ornament though.
 
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