Soldering oven, another daft idea?

[John Hill]

There are a lot of parts in my atmospheric engine project that I need to assemble with a water tight seal.  All the parts are mild steel.

Due to the available facilities I am considering soft soldering and specifically oven soldering.  The idea is to 'tin' the mating surfaces, assemble the bits then heat in an oven so that the solder flows and I get a good seal.

Problem:  I dont have a suitable oven!

Maybe I can make an oven of bricks and mount a hot air gun to blow hot air in and heat everything,  gun claims 650C  and 2000W.  Is this another daft idea?

N.B.  I dont want to use a flame to heat as the combustion products foul the solder joins.

[AussieJimG]

That sounds like a rather clever idea John.

I am about to try my hand at one of Jan Ridders' Egg Cup Stirling engines for which he says the crankshaft should be soldered. I had been trying to figure out how to do this without pushing the pieces out of place with the soldering iron.

I am still a few weeks away from making the crankshaft but guess what I am going to try. http://madmodder.net/Smileys/default/happy0065.gif

Jim

[bp]

I agree with Jim....a good idea, certainly worth pursuing!  My first thought was that it seems similar to a sort of low temperature "dip brazing" for use with al. alloy.
From memory soft solder melts at something around 450 degrees C, but solder for electronics is something less I believe.  No doubt the temperature range is governed by the makeup of the solder.
Certainly worth experimenting with.
Best of luck
cheers
Bill

[75Plus]

60/40 solder, as used on electronics, melts at around 370 degrees F which is well inside the range of kitchen ovens.

Joe

[Lew_Merrick_PE]

60/40 solder, as used on electronics, melts at around 370 degrees F which is well inside the range of kitchen ovens.

And failing that, using two oven elements (which can usually withstand 800°F for quite a while) mounted inside a refractory brick enclosure will often do the trick.  Wiring 220 VAC (assuming U.S. oven elements) requires attention to detail but is not too hard.  ???

[Swarfing]

You could go for something like this on a smaller scale.

http://www.priority1signs.com/index.php?id=491

[Joules]

Interesting John,  could you use a toasty oven ?  lot of the surface mount guys rework them for flow soldering.   My only concern with using the heat gun would be the need for a baffle, so nothing gets the full force of 650c