Help with solder.

[longrifleman]

Any one have any tips on soldering? I need to put sight ramps on a single barrel shotgun and am having trouble with the process. I haven't tried it on the gun yet as I want to get it right the first time(right!). When I try to tin the parts I can't seem to get an even coat of solder.

I am using an oxy-acetylene torch with a small welding tip for heat. I couldn't seem to get enough heat to the metal with a propane torch.

It is Brownells High Force 44 solder.

Any ideas would be GREATLY appreciated. (I've already thought of taking it to someone who actually knows what they are doing but where's the fun in that.)

 

[JA]

First thing is cleaning the parts and type of flux used. All parts have to be down to bare shiny metal. Using a chemical to do this leaves residue in the pores of the metal. So grinding,sandpaper,etc should be used. No bluing,rust,oil,finger prints,etc....left on the parts. Go to Wal-mart and get a spray can of brake parts cleaner. This is the best I have found as it will clean all oil off,evaporates fast,and leaves no residue. It is only $2 a can so really hose the parts down with it. What type flux are you using?
The next most encountered problem is using a torch tip that is too big and having the gas pressures set too high. Follow mfgs. recomended pressure settings for that tip.
Welding or heating tip? Smallest size tip they make?

 

[mete]

Like JA says clean thoroughly and after it's clean don't touch it ! Use flux recommended for that solder. You only need a very thin layer of solder, anything more than that should be wiped off.

 

[P95Carry]

I am not familiar with the alloying of your solder but .. as mentioned .... preparation is everything.

Then .... re the flame ... now I use some old nozzles and they start from #1, then #2, then #3 .... then #5, then #7 .. and so on. This job sounds like a #3 to #5 but I'd have to measure my nozzle dia's to be of much help to you I suspect.

This counts pretty much as a ''brazing'' operation as against steel/steel welding. I would use a very slightly ''carburizing'' flame ... so you have some acetylene flame showing ahead of the oxy inner cone.

MOST important thing IMO .. is .... do NOT burn your flux!! Once prep'd and bare metal, heat with the flame not directly impinging on that bright metal . just to side instead or under (as with a rib) ... once up to temp the flux should show some slight bubbling and careful wiping on of solder rod should show when MP reached ... and then some flow.

Before heat lost too much ... wipe off excess .. it is ''tinned''. Repeat for sight unit and once that also is tinned - leave a small amount of solder on it ... just a ''film''. ... ... place on rib and bring both up to temp until a slight and almost imperceptible ''ooze'' shows at the interface. Remove heat and allow to cool.

You may wish to place some heat sinking paste a short distance away from area of operation ... but note ..... it is better to have a slightly generous heat input - and get the work up to temp quickly ... too low a heat and you'll be heating it all day .. whilst that heat travels to where you don't want it!

 

[bountyhunter]

Most fluxes for soldering steel are acid flux. Be REALLY careful not to let it touch anything else and apply it carefully. Also, make sur you wash your hands thoroughly before touching the gun again or you will end up acid etching your fingerprints into it. Afterwards, neatralize it with running water and then oil it up generously.