Braze or solder broken cast iron plane sides?

[sploo]

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):

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?

 

[okeydokey]

Could you buy another body and cut off the side you need and then have it welded on.
Or if you bought a whole plane the unused parts Could be sold to get most of your money back

 

[Bingy man]

It’s possible plumbers solder would work but I think your problem will be the steel will will get far too hot for it to work. Solder is designed for copper / Tin etc which heats up to temp quite quickly therefore it’s easy for the solder to run. Brasss rods have a higher melting point therefore are more suited to brazing steel but yes the colour difference stands out . A weld however can be ground back with little or no visible evidence.

 

[Dee J]

A brass brazed repair could have a kintsugi vibe... Complete but tells its history Kintsugi - Wikipedia.

 

[sploo]

It’s possible plumbers solder would work but I think your problem will be the steel will will get far too hot for it to work. Solder is designed for copper / Tin etc which heats up to temp quite quickly therefore it’s easy for the solder to run. Brasss rods have a higher melting point therefore are more suited to brazing steel but yes the colour difference stands out . A weld however can be ground back with little or no visible evidence.

Interesting. Can't weld it unfortunately as apparently welding cast iron is quite difficult, and with only a cheap gasless MIG welder (and no talent) I fear I'd make a right mess of it.

Could you buy another body and cut off the side you need and then have it welded on.
Or if you bought a whole plane the unused parts Could be sold to get most of your money back

Should be fairly cheap to buy some cast iron and mill it to shape. I'd feel like a right vandal destroying another plane

 

[Bingy man]

in that case could you have it welded by a experienced metal worker - there may be some on this forum that can either help you or suggest someone or somewhere you have it done for you -I guess there will be some risk either way to weld cast iron ( sorry previously assumed it was steel )

 

[Fergie 307]

I am afraid there is no way you are going to be able to repair that easily. To weld or braze cast iron effectively you need to get the whole piece up to a good temperature. Something as thin as that will warp all over the place, so would have to be 're machined to get it flat and square afterwards. Personally I would just clean up the edges and use it as it is.

 

[John Hall]

It would braze ok, but would also look obviously repaired. You can get cast iron welding rods which would match the colour, but would need to be in the hands of an experienced welder. Expensive too..

 

[OldGreyDog]

Silver soldering a new bit on might work?

 

[sploo]

Yea, wondering about silver soldering as I assume the required temperature might be a bit lower? As that area would purely be a cosmetic repair it doesn't need to be that mechanically strong.

I do take Fergie's point about cleaning the edge up and leaving as is though. Not what I want to do, but certainly preferable to damaging it further with too much heat.

 

[cerro]

A TIG AC/DC welder would do it no problem I am looking to buy the cheapest one when I sell my MIG. IPtools TIG INV 185 AC/DC and looking on youtube it seems to weld all metals cast, steel, aluminium, brass, copper. It also has a built in stick welder for thick steel. But anyone with a TIG will do it for you.

 

[OldGreyDog]

Yea, wondering about silver soldering as I assume the required temperature might be a bit lower? As that area would purely be a cosmetic repair it doesn't need to be that mechanically strong.

I do take Fergie's point about cleaning the edge up and leaving as is though. Not what I want to do, but certainly preferable to damaging it further with too much heat.

Silver solder will likely be a better colour match, but its plenty strong enough. Top level lugged type bicycle frames were silver soldered when very thin wall tubing was used. Reynolds 753 tubing had to be silver soldered and frame builders had to be licenced by Reynolds before they were supplied with that type. If its strong enough for pro bike riders frames…

 

[Vann]

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...

...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?

1. Applying a lot of heat to thin cast iron risks distortion - but can work, albeit sometimes requiring some surface grinding to true things up.

2. I doubt soldering would work for more than 5 minutes.

3. Silver soldering may work, but will have a colour difference.

4 Brazing (using brass rod) will work, but as you say has a very obvious colour difference.

5. Cast iron welding will probably give the best result, but requires the most skill (= cost).

However, here's a pikkie of my three "go to" planes.

The nearest is a modern (~2010) Clifton No.3.
The next is a "warfinish" Record No.04ss. As you can see it has a chunk off the far side - but it's a great user - a favorite.
The last is a Record No.05. This has a brase repair - but it does everything I ask of it.

Being a bottom feeder I've bought a number of planes with repairs. Probably in 50% of cases the repair didn't go well and the planes are good only for parts.

A plane in mint condition is nice - but it's not a necessity. The missing wing on your plane is just a battle scar and, assuming you didn't break it, it's part of its history. Consider tidying it up and using it as it is.

Attempting to repair it may make it look nicer - but equally it may distort it, ruin it, and/or cost you more money than the plane is worth.

My tuppence worth.

Cheers, Vann.

 

[sploo]

I've repaired/restored tens of old planes over the years (there should probably be a Planeaholics Anonymous for people who can't resist buying and fixing "lost dogs" ) but I've never tried brazing or soldering any parts of a broken plane sole (that's always been my red line for buying one). However, this plane belonged to a great grandfather - hence the attraction for trying to fix it.

I've ordered some (what I understand is) decent quality silver solder and flux, so I'll get some scrap cast iron and see how it goes before I get a torch near the plane.

 

[hawkeyefxr]

I have welded cast iron a little years ago, arc weld. It would need some pre heating then welding. To weld it straight off can cause stress and possible cracking later as it cools.
Cast is 'dirty metal so i would say silver solder will not take very well as silver solder likes the suraces quite clean.

 

[John Hall]

https://www.model-engineer.co.uk/forums/postings.asp?th=118175

 

[Fergie 307]

I have welded cast iron a little years ago, arc weld. It would need some pre heating then welding. To weld it straight off can cause stress and possible cracking later as it cools.
Cast is 'dirty metal so i would say silver solder will not take very well as silver solder likes the suraces quite clean.

that's why you need to get it pretty hot all over, to avoid stress around the repair, which will cause it to crack later. Your best bet would be to get it up to a good temperature using a Mapp torch, then whilst maintaining the temperature with the Mapp, use oxy acetylene to raise the temperature at the repair site the extra bit for your brazing rods to work, or preferably weld it. You can get specialist rods for stick welding cast iron and these are very good for this sort of small job. After making the repair put it in a bucket half full of dry sand, then fill up with more sand on top. This will stop it cooling too quickly, if you can heat the sand up as well so much the better. Leave it until fully cooled, then you may need to machine it to get it flat and the sides square. My concern would be that something this thin might warp to the extent that you would need to remove an excessive amount to get it true again. Repairs I have done on thin stuff like this have mostly been decorative items where being absolutely true afterwards isn't especially important, they can distort quite a bit. I suppose you could clamp it to a section of heavy steel plate or channel to help keep it true during the repair, although I have never tried this.

 

[Torx]

A TIG AC/DC welder would do it no problem I am looking to buy the cheapest one when I sell my MIG. IPtools TIG INV 185 AC/DC and looking on youtube it seems to weld all metals cast, steel, aluminium, brass, copper. It also has a built in stick welder for thick steel. But anyone with a TIG will do it for you.

I’ve got a Tig and I’m not doing it

Joking aside, having the equipment and having the experience and skill to make a good repair on something like that are two different things, especially when it comes to Tig which is a steep learning curve.

What about cutting the other side off too and making a pair of brass sides for it, screwed or brazed in place?

I think whatever you do would need a bit of machining afterwards.

 

[TFrench]

Personally I'd leave well enough alone. It's part of the story of the tool.
And @cerro , I wouldn't attempt that with my tig either. Too much chance of killing it for good.

 

[KeenToLearn]

You can get "cold" arc welding rods specifically for cast iron. Trick is just to do a bit at a time so it doesn't get too hot and distort. Not hard to use if you have used an arc welder before I can assure you