silver solder tips?

29 September 2018, 01:14

NRDock

silver solder tips?

Last winter I tried using Brownell's high force 44 solder + their recommended flux, and it didn't really work out for me. Ok, I was out in the cold garage, and in a hurry, so I didn't necessarily give it my best effort. I don't remember if I used propane or the oxy acetylene torch. I managed to get half the carbon steel part tinned, and none of the stainless part. I definitely overheated the flux a time or two.

Soldering copper pipes was child's play compared to this. Are there any tricks to working with this stuff?

29 September 2018, 02:54

p dog shooter

Proper prep is the key to soldering.

Both parts have to be very clean and dry.

Propane well not get hot enough for silver solder.

29 September 2018, 03:09

kendog

quote:
Originally posted by p dog shooter:
Proper prep is the key to soldering.

Both parts have to be very clean and dry.

Propane well not get hot enough for silver solder.

Bright clean metal is a must. Fluxing the solder cant hurt, the acid cleans off oxidation. Propane will work fine on Hi Force 44. Overheating will cause problems too. Heat the work slowly and gradually till the solder starts to wet and run with the flux. Apply heat to the biggest mass and melt the solder with the hot work, not the flame.

29 September 2018, 04:12

MNR

Soldering with high force is definitely more difficult than lead solder and copper pipes. Like others have said, most of the work is done in prep. Lots of practice will help you with heat control. It doesn't need the heat of silver solder (only about 400 degrees) but I still prefer oxy/acetylene over propane (I'm impatient). Just know things can go bad real quick if you're not paying attention to the heat.

29 September 2018, 05:02

dpcd

Force 44 is not hi temp and propane works fine; no harder to do than lead/tin; in fact, amateurs will get into trouble using acetylene.
And it is not "silver" solder; It is tin with only 5% silver. Everyone calls anything silver in color silver solder; it ain't.
Silver solder (really a brazing process; over 840 F) is high temp and is not for amateurs.
And not needed for guns.
Prep is only part of it; if you burn your flux, then start over.

29 September 2018, 14:34

lost okie

Prep and heat control is every thing. Tin your SS part first; if at all possible. If it won't tin then you know where your problem lies.

29 September 2018, 20:14

Lapidary

quote:
Originally posted by dpcd:
Force 44 is not hi temp and propane works fine; no harder to do than lead/tin; in fact, amateurs will get into trouble using acetylene.
And it is not "silver" solder; It is tin with only 5% silver. Everyone calls anything silver in color silver solder; it ain't.
Silver solder (really a brazing process; over 840 F) is high temp and is not for amateurs.
And not needed for guns.
Prep is only part of it; if you burn your flux, then start over.

Man, I'm with you. I wish people would stop calling anything with a trace of silver in it "silver solder". True silver solders contain 50-85% silver and flow at 1200-1500 degrees F. They aren't used in gunsmithing.

30 September 2018, 04:28

jeffeosso

the stainless part may give you fits, it not clean and acetone wipes.. the flux for force 44 is a nightmare for cleaning .. "tin" both sides, and force 44 will run uphill from a propane torch ..

30 September 2018, 22:58

Dans40XC

Clean,Flux,Fixture,Braze.

If you burn the flux....start over.

If you need to "TIN" parts....seek a professional.

01 October 2018, 02:30

jeffeosso

quote:
Originally posted by Dans40XC:

If you need to "TIN" parts....seek a professional.

cute ---
and brownell's EXACT directions

https://www.brownells.com/userdocs/learn/Inst-345.pdf

quote:
When two pieces are to be joined, it is often best to “tin” each of the pieces.
“Tinning” is a procedure where a thin coat of solder is applied to the work pieces
where they will join. The procedure is simple; first clean, heat and
flux the bottom surface of the first part and apply a very thin coat of solder
to the joining surface. Remove any excess solder while it is still molten with
a clean, cotton patch or felt cloth.
Follow the same procedure on the joining surface of the second part.After
both have cooled to where they can be handled, position them as needed for
final assembly and clamp together. Apply heat carefully to BOTH parts so
both come up to the desired soldering temperature, 475° F., simultaneously.
At this point the solder will flow and cool;the two parts will be firmly joined.
It is often helpful to use a small amount of flux between the two tinned parts
when bringing them up to temperature.

01 October 2018, 03:30

Dans40XC

Tinning is for rookies!

Run Up Hill-
The HEAT will pull the flow.
DUH!

Not my first rodeo

01 October 2018, 04:41

Doug W

quote:
Originally posted by Dans40XC:
Tinning is for rookies!

Psssss....... the OP by his own admission is a rookie.

01 October 2018, 07:05

NRDock

In retrospect, I probably cleaned with the wire wheel, which must have some oil in it. Any recommendation on clearance between male and female cylindrical parts?

Next weekend, I'll bring the oil less air compressor home from the work house, clean with acetone, bead blast, join parts, and move on the the next phase. Thanks for all the help.

01 October 2018, 10:51

eagle27

I've used Silfos 15 (15% silver alloy) for many years and it is brilliant. I use a fine oxy/acetylene torch, clean parts, heat rod, dip into white powder flux and go to it. Flows very cleanly. Even silfos up cracks in the necks of my old 404 Jeffery cases for use with cast loads, sit neck over a dirty steel rod mandrel, usually very little clean up required. Necks anneal well and cases live on.