Soldering front sight on round barrel

[nchunter]

I've tried three times to solder the front sight on my fowler. Every time it ends up slightly crooked, with solder runs or globs all around it.

How do you guys get your front sights soldered so cleanly and straight?  I know how to mark the top of the barrel, that's not the problem. The problem is the barrel is round, so everything wants to roll all around and down the sides.

[smylee grouch]

I flux and tin both sight and barrel and I filed a grove into the face of a C clamp to hold the sight when I reheat the solder.

[satwel]

I have achieved good results by using a bent hacksaw blade to hold the sight (or lugs for pins) in place while I gently heat the barrel enough to melt the solder. I cut one end of a hacksaw blade square and file a small notch in it. I then bend the blade to a right angle about two or three inches from the notched end. I clamp the other end of the hacksaw blade to the top of the barrel with a spring clamp from which the plastic protectors have been removed. I lift the bent end of the hacksaw blade and slide the sight under it into the prepared position on the top of the barrel; with the blade of the sight in the notch. The hacksaw blade provides just enough pressure, straight down, to hold the sight in place without causing it to slip and slide when the solder melts. The thinner the layer of solder on the bottom of the sight - the less it moves when the solder melts plus there is less runoff to cleanup.

[Long Ears]

X2 on how Smylee does it. As far as straight you just need more practice. I still have to redo one sometimes. Bob

[Dave B]

I have had problems with a the settling of the sight once the solder flows when using a ridiged C clamp. I like a spring steel  portion that keeps the sight in place and constant tension so when the solder flows the sight wont slip. I think I saw Don Getz post something of the sort but I cant find it. Mine is nothing more than a section of spring steel that is 1/16" thick x .5" x  4" with a notched end bent down so the blade is trapped in place when the other end of the steel is clamped to the barrel with a C clamp or stout spring clamp.

[smylee grouch]

Thanks for the tip satell and dave. I will give it a try even though the method I have used works. Its nice to know of different ways to do things.

[Acer Saccharum]

This has been talked a lot about over the years.
Potential resources: Eric vonAschwege recently posted his method. There might be tutorials as well.

[J. Talbert]

This is a perfect job for Paste solder, available from Brownells.  Or as I call it, soldering for Dummies.   
Use the clamping method of your choice .  I like the bent hack saw blade.

The paste solder is a mixture of ground up solder suspended in flux.  It's the simplest to use that I know of.  Clean the surfaces.  Spread a little paste on the part.  Clamp in place.  Heat until the flux bubbles out.  Let cool and clean up.  Most of the flux residue will rinse right off

Jeff

[Dave B]

You guys have heard me say this before but the use of a soldering copper or copper slug slid into the bore at the place immediately under the solder joint will help get the heavier barrel up to temp and prevent over heating of the flux.  I have in the past struggle with getting in a hurry and burning the flux before every thing is up to temp. The copper slug has helped me prevent this.

[C Wallingford]

This is a perfect job for Paste solder, available from Brownells.  Or as I call it, soldering for Dummies.   
Use the clamping method of your choice .  I like the bent hack saw blade.

The paste solder is a mixture of ground up solder suspended in flux.  It's the simplest to use that I know of.  Clean the surfaces.  Spread a little paste on the part.  Clamp in place.  Heat until the flux bubbles out.  Let cool and clean up.  Most of the flux residue will rinse right off

Jeff

Brownell's now shows the Swif 95 as discontinued.

[Dennis Glazener]

I am sure paste solder would work better but I just use a hammer to flatten out a piece of regular acid core solder, smear a little of solder flux on the barrel, a little on the base of the sight. Place thin flattened solder between barrel and sight, use a piece of spring steel to hold pressure on it as described above. Heat slowly and as soon as you see the base bottom on the barrel remove heat. Don't use but a tiny bit of solder else it runs down the barrel! I have done several sights and barrel lugs this way and have never had one come loose.
Dennis

[Kermit]

What Dennis said. You can tap on that solder until it approaches one molecule thick. Get it really thin, not just sort of thinnish. I did the barrel lugs this way to practice before attempting a sight.

[chubby]

Hi fellow builders, I  agree on all of the soldering tips, but one thing i do is to pull a piece of 220 metal sanding paper around the barrel where i am going to solder. this way the front sight radius will match the radii of the barrel! this will stop the sight from moving side to side and stay on your center line while soldering.this works good for me.  Chubby!

[chubby]

Opps, forgot to mention abrasive side up and sand bottom of sight, sorry  Chubby

[Karl Kunkel]

Disclaimer: I've never had to try and solder a sight on.  Is there a reason you couldn't use the bent hacksaw blade spring clamp method, but position the barrel upside down, with the sight on the bottom?  (Then you wouldn't have solder running down the sides of the barrel.)

[frogwalking]

I found an old welding clamp that looks as if it were made from a pair of vice grip pliars.  I filed grooves on both of the clamp ends, and this gives me a clamping force to hold the sight, plus the spring pushes it tighter if needed when the solder melts.  It seldom slithers around, and usually stays where I clamp it.

[flehto]

After both the sight and bbl surface have beeen sanded and mated, the sight is positioned  on the bbl and the base is outlined w/ a pencil. W/in the outline, Swif 95 solder paste is sparingly applied  and also to the sight.  The sight is placed on the bbl  and loosely  held in place w/ the clamp shown below, the "V" is centered on the blade and a clamp applies force on the small, horizontal length.When the sight has it's correct position, the clamp is tightened some more. Heat is applied mainly to the bbl and the job is quickly done. The clamp is made from 1/8" thick steel.......Fred

[gwill]

What a great setup. I have a question that must have a simple answer. How do you find the exact "top" of the barrel for marking the location for the front sight?

[ddoyle]

Maybe (look for confirmation from someone who has actually built a gun ): Level the barrel in a vise, lay a level on a file and draw it along the top of the barrel keeping the file level. 

[Artificer]

What a great setup. I have a question that must have a simple answer. How do you find the exact "top" of the barrel for marking the location for the front sight?

These are ways to do it when you don't have a Mill.

It is much easier if you already have a rear sight in place to lay something like a steel rule on top the rear sight and use another steel rule like a winding stick on the front of the barrel.  If no rear sight is in place, you lay the rear steel rule "Winding Stick"  across the top of the tang.  Then mark where the front "winding stick" contacts the barrel.

Or, if you have a set up like Frogwallking showed above, you can eyeball the front sight blade to set it where it appears correctly vertical to the eye.

Finally, if you REALLY want to get persnickety, you use an angle finder on top the rear sight or tang and hold a steel rule against the side of the front sight blade so you get a 90degree difference and mark where the front sight should go.  (I do this when barreling M1 Carbine barrels as you can not trust the witness marks on the barrels and receivers.)
Gus.