Re: brass brazing ? any one help ??

mcevoyi · Post by **mcevoyi** » Wed May 20, 2009 4:38 pm

hi all

i wounder if any one has time to eplane how to braze bits of brass together ?

as i would like to make a set of frames to hang side skirts from for a pz4

plastic rod and char just to hack it when up against grass and like

iain

fv432 · Post by **fv432** » Wed May 20, 2009 4:49 pm

cant you do it with solder ?

mcevoyi · Post by **mcevoyi** » Wed May 20, 2009 5:03 pm

i thought about solder

but its just not stong enough .....

BREL · Post by **BREL** » Wed May 20, 2009 5:18 pm

have a look at this page

http://www.technologystudent.com/joints/braz2.htm

fv432 · Post by **fv432** » Wed May 20, 2009 5:23 pm

could try silver solder more heat involved and expense would do the job though

Ex_Pat_Tanker · Post by **Ex_Pat_Tanker** » Wed May 20, 2009 9:38 pm

I've soldered brass kits together before, you just need the right solder and flux to get things goings - check the model railway magazines, I think 'Carr' was the brand I used.

971wright · Post by **971wright** » Wed May 20, 2009 10:07 pm

Hi Brazing is the stronger but it does require alot of heat which you will struggle to reach with a butane or propane blow torch the temperture required is around 700 degrees f siver solder is around 450 f .If you get a good clean solder joint it will be strong enough to hold and you wont need welding equipement.I can bet you that a solder joint will not break the tank will .

regards pete

Aus_Tank · Post by **Aus_Tank** » Thu May 21, 2009 11:20 am

I use a resistance soldering unit for all of my none electronics soldering. Some of you may have heard of "American Beauty", well mine is similar but a bit cheaper....

This was built be a guy in Sydney for me about 18mths ago. The advantage of this over a normal soldering iron is that you can direct quite a bit of heat to a very small area. Another plus is the strength of the joint.

Regards,

Phill

mcevoyi · Post by **mcevoyi** » Fri May 22, 2009 4:35 pm

thanks all for all the help

most brill

now next problem ...

brass strip .... any one name a good supplyier .... i live in the west country bridgewater .. have a model shop that sales k&s brass .. but nothing in the standard range to do the job.... want to make the hangers for armourd skirting on a pz4 ...

BigPanzer · Post by **BigPanzer** » Sat May 23, 2009 2:44 pm

Hi Iain,

Don't bother trying to braze, the temperature needed is too high and you are likely to distort or even melt the bits of brass you are trying to solder!

I use silver solder and prefer Easy-Flo Number 2, which is VERY strong and has a much lower melt and re-melt temperature.

If you are going to try it, get the thinnest rod of it you can and a tub of Easy-Flo flux. You will also need some fire bricks to retain the heat and flame and a source of heat. I use a Camping Gas blowlamp and it works well.

Mix a tiny bit of the flux with a drop or two of water to make a thick, non runny paste and apply it to the cleaned brass that you want to join. Heat it up and when it starts to go red touch the joint lightly with the solder stick. The solder will flow into the joint almost instantly and stick to where the flux was applied.
Silver soldering is not good for filling in big gaps - it works by capiliary action sucking the liquid solder into the joint and the more you apply then the more you have to clean up with a file afterwards.
Going from memory, I think there is a difference of about 30 deg. between the melt and re-melt temperatures.

Silver soldering is an art, and to get a good job you need practice. However it is a very useful skill to have for all model makers.

The electric method is also quite good, and used professionally by jewellers but I've never quite mastered it.

Solder and fluxes are sold by model engineering suppliers such as Reeves.

Peter