Metal brazing with map gas

tomlad

Member
Location
nr. preston
As title, i haven't done much brazing, presumably i can with oxy prop but can i with my plumbers map ?
Job being attempting to repair minor leak on water jacket ,boiler . In fire box side .
I don't want to try stick , presumably solder won't like the heat.
Last gasp on buggered system.
 

Stock

Member
If you can clean it well enough have plenty of Borax flux and if the heat is sufficient it should work..........................................no guarantees though...................................................................................................
 

TheTallGuy

Member
Location
Cambridgeshire
It's just about barely possible to braze with MAPP & similar without oxy, but getting enough heat into stuff can be an issue - especially when using a basic plumbing torch.
 

tomlad

Member
Location
nr. preston
Thanks for info I'll have a play on bench wen i get chance, boiler in kitchen so leads may not reach.

Possibly a excuse to buy that nice torch like doubleboost rates ...
 

Andy Nash

Member
Arable Farmer
is it possible to get acetylene in decent size bottles, without the BOC rent I wonder?
Yes Gas Uk. I have acetylene in a 10litre bottle. Pay a deposit on the bottle once then just pay for refills.
Same with oxy.
I don’t think MAPP will be hot enough either.
 

Dry Rot

Member
Livestock Farmer
I have never brazed and don't know what mapp is! But I have done some silver soldering. There are solders that melt at a whole range of temperatures, just need to choose the correct one. Google 'eutectic". Also try Amazon. There are special fluxes for different jobs. Soldering stainless steel with a propane torch was no problem once I had the correct flux. Sure to be information on Youtube. Brazing does require a higher temperature, I think that's why I didn't use it.
 

tomlad

Member
Location
nr. preston
Simply NO., it may appear you. Have done a job but it will just peal off
Braze wont stick ? Honest question 🤔
Or map wont have got it hot enough
I believe solder will seel it but then probably melt with the fire 🔥
I know this is a bodge.
Also a vertical surface so that isn't helping a repair is it.
Potential to protect the repair with fire board afterwards while we figure out new system
 

Andy Nash

Member
Arable Farmer
Both.
The steel wants to be hot enough to be just hot enough to be sweating a bit, then the braze melts into it with plenty of flux. It’s not enough just to melt it on to it like with solder.
Think it might be hard to get it clean enough to braze. Vertical surface will be a challenge too!
 

tomlad

Member
Location
nr. preston
Steel , not cast , welded joints then heat treated i believe. ( according to importer , wamsler German).
I have patched it before with mild steel plate and dissimilar rods but it was more luck than owt , vertical, pillark to get water tight. Hence i don't want to blow my pin pr*ck into a big hole.
Would not be simple to turn over for down hand.

Obviously its fooked but last chance bodge.
 

Abacus

Member
Mixed Farmer
Location
South east
screw with a copper wosher may work but if the boiler is not thick enough for the tek screw to get hold it whont work maybe a heavy secshon one would be better
 

Dry Rot

Member
Livestock Farmer
You need a copy of the Welding Data Book published by Eutectic Company Ltd. I am not sure if it is still in print but the used book trade will find you one (Google 'Book Search'). Or find a company that uses eutectic, phone them up and ask. The worst that can happen is they tell you to do one!

There are welds, brazes, solders, stick and electric, for every conceivable purpose that melt as a whole range of temperatures and solders for use with any metal. The OP does not have a big problem, just needs an answer.
 

SFI - What % were you taking out of production?

  • 0 %

    Votes: 80 42.3%
  • Up to 25%

    Votes: 66 34.9%
  • 25-50%

    Votes: 30 15.9%
  • 50-75%

    Votes: 3 1.6%
  • 75-100%

    Votes: 3 1.6%
  • 100% I’ve had enough of farming!

    Votes: 7 3.7%

Red Tractor drops launch of green farming scheme amid anger from farmers

  • 1,293
  • 1
As reported in Independent


quote: “Red Tractor has confirmed it is dropping plans to launch its green farming assurance standard in April“

read the TFF thread here: https://thefarmingforum.co.uk/index.php?threads/gfc-was-to-go-ahead-now-not-going-ahead.405234/
Top