Joining brass to mild steel

[Mikey D]

Ive a little repair to do on an oil seperator , its on a total loss lubicated vacuum pump .
basically theres a brass nipple which needs refixing into sheet steel about 1mm thick ,
i 'think 'it will have to be brazed , ok so if it cab be brazed what rod do i need and can it be done with propane or mapp gas with a plumbers type blowlamp ?
its ages since i brazed amything ie at skool 25 yrs ago
but i seem to remember coated rods so no flux needed ? or do i need flux too?

cheers mike

 

[jugs]

Silver solder (brazing (bronze welding) is too hot & would melt your brass nipple).

Clean parts with citric acid & wash with clean water, put small amount of flux in joint, In a darkened area, use a propane torch to heat till brass is a dull red, touch Silver solder wire on joint @the correct temp it will melt & go into joint by capillary action. Clean again with citric acid & wash with clean water, job done.

Try not to use a paraffin plumbers blow lamp (dirty flame = dirty joint).

 

[bill_gj]

Silver solder might be a better option - less heat and relativley easy to control.

 

[English Steve]

Yup, as said already, silver solder is the way to go - you will need flux. Depends how big the nipple is but you should be able to do it with a plumbers propane blowlamp.
I restored a church key last year and had to get the O/A out to silver solder the end on, simply because I couldn't get it hot enough with the blowlamp.

 

[Arsonista]

That's a nice site Steve. Petters in Staines?

 

[madkayaker]

nice job

 

[English Steve]

Thanks chaps.
Not Petter Staines, Wallace was there though - I was based at Petter Hamble, near Southampton - same company but we used the engines which Staines built, if that makes sense.
If you've looked at my site, you will notice that I am definitely NOT a photographer

 

[Arsonista]

Steve, if you were a good photographer, a good engineer and owned two Metisse's, people might start to go off you.

I've got a picture on my wall of The Causeway' in Staines, showing Petters corner with the old gas lights. Sad, moi?

 

[Mikey D]

Cheers guys ,silver solder it is then , next question where do i buy one "piece " of silver solder and a very small amount of flux ,
tthis is definatly a one off job , maybe i will try some rapid araldite instred

cheers mike

 

[madkayaker]

have used the chemical metal stuff and found it good. Not used it on brass though

 

[Mikey D]

Ha , thanks mk , im sure ive got some tucked away somewhere !

just looked found it JB WELD , says on the packet " Americas toughest weld!"

What does that say about american members ?

cheers mike

 

[madkayaker]

that's the stuff i used to repair a crack in gearbox casing on a car even after i had had head to head with a truck it was still good

 

[English Steve]

MikeyD, have a look here for silver solder and fluxes in small quantities (ie one stick).

 

[..DAZ..]

If you struggle to get just a couple of sticks let me know. My local hardware/ironmongers sell it by the stick and I could get some for you and post it, although I am sure you will find someone a bit more local. Still remember the first time I asked for a box, the guy looked at me like I was stupid "Are you sure you want a whole box"?
"Yeah" I said..............until he told me the price!!! After which my reply was "do you sell it by the stick"? I was an apprentice at the time and it cost more than my months wages!

cheers
daz

 

[..DAZ..]

Theres a late thought or two, you might get away with copper rods and some powder flux, and secondly I remember I have both copper and silver rods in the shed, so if you don't have any joy local, give me a shout.

cheers
daz

 

[Mikey D]

cheers for the help guys ive already had an offer to send me some via pm , im gonna try the liquid metal bodge first tho

regards mike

 

[swampy395]

silver solder

Hello every body

i'm new to this forum some nice tips here guys thanks

I use silver solder on fridge/air con systems

here's some info "silver solder" comes in wire form, From 3% to 38% silver, I only buy the 38% as this doe's steel to brass n steel to copper and will withstand pressure tests at 35 bar, it also sticks to most other things too

The lower % will do copper to brass OK and is also a bit gloopy to use

so the higher the % you use the easier it is to use and the stronger the joint

P.S. you can buy it at most Refridgeration/Air conditioning wholesalers over the counter 1 stick at a time

some UK wholesalers
HRP
Climate centre
dean & woods
Kooltech


hope this help's someone

best regards

ian