Dovetailing barrel lugs or solder

[oldtravler61]

While at the TN show I bought a southern classic squirrel barrel 44 inch from Jason of Rice barrel in 36. To say this barrel is slim is an understatement. Would it be better to solder the lugs on or dovetail them in. Wondering about the heat on the barrel. Or risk of cutting  to deep. I like to do everything myself(stubborn) What yeah all think? Have done other barrels but this one hmmmm

[WKevinD]

Your center underlug is  iffy in .50 but you should be OK with .36 if your careful. My thoughts; inlet shallow and solder with soft solder. Measure barrel OD (at the underlug position) subtract ID divide by two for your wall thickness, then approach carefully.

[oldtravler61]

Thanks burnt. Much appreciated advice.

[Jerry V Lape]

I just did underlugs on a Rice barrel in .40cal.  When calculating bore diameter don't forget to add in two x rifling depth to the .40.  Guys at Rice said with roundbottom rifling the depth is .o15" so the bore worst case is .403".  I did a very shallow dovetail of .035", thinned the bottom of the lug to a matching thickness and staked them in without solder.  They seem plenty strong and I have more than .10" wall thickness on the weakest point which happens to be the lug closest to the muzzle where pressure is lowest. I did not put a lug in the waist.  The other two lugs have a thicker barrel wall and are plenty strong.  If they should ever fail I can easily solder in the next ones. 

[Mark Elliott]

The major barrel makers design barrels so that you can put in a .040" deep slot and still have at least .10" of barrel wall.    I generally try not to put a slot in the thinnest part of the barrel.   Usually, you can avoid it by putting slots to either side of the waist.

[kutter]

I've been simply soldering them on (sweat solder) of late.
No dovetail to cut in the bbl, no dovetail to shape on  lug itself & no fitting of the two.
Simple flat surfaces for oct bbls are easy to fit perfectly.

(we already do solder them on rd bbls anyway and they hold just fine).

Make the base a little longer if you want more surface contact for soldering, the tab the pin runs through doesn't have to be as long though.

Nothing but 50/50, 60/40 or the ' lead free' silver solder (tin and small % of silver) is needed.

They're all  soft solders so no damage to the parts.

[B.Habermehl]

I have to agree with Kutter. Any more if there is going to be a lug anywhere near the waist of a barrel, out comes the torch, flux, and solder. It also has the benefit of allowing your pin holes to be closer in line, so running a molding carving looks a bit better with the pin holes at regular spacing from the molding. At least the last time it did and made my fussy streak smile. BJH

[frogwalking]

I am working on a Southern Classic in .40 caliber right now.  I measured the smallest part of the waist at O.764 inches.  The bore, allowing .015 deep grooves is .0430.  This makes the minimum wall thickness O.167 inches.  If one cuts the dovetails the full depth of TOW tennons (.050), this leaves 0.117 inch.  At the rear tennon location where the pressure will be greater, the barrel is much thicker.  I file the tennons to .40 just for added safety. 

I just finished a .40 cal. using a very small swamped barrel from Rice.  I did solder the tennons on that rifle. the waist dimension is 0.660 inch.  This means the barrel was only 0.115 thick in the waist without any dovetail.

[oldtravler61]

Thank you everyone. Going with the solder. Starting to inlet the barrel tomorrow. Have three rifles going right now. Two 36 cal an a forty. A soddy, a Tennessee an a southern style. Going to be a fun summer!

[David R. Pennington]

I dovetail the front and back ones and solder the middle ones on a skinny swamped barrel.

[Ridge]

I have a quick question that may seem obvious to you guys, but I'm going to ask it anyway!

How do you hold the underlug in place while you solder?  My first thought is a little C clamp, but I'm wondering if that would just suck up the heat and make it harder.

Also, if I'm reading this correctly, you are just using regular plumbing solder?  Not silver?  How about electrical?  Will it matter?

Thanks.  This may be an issue for me shortly.

[Smoketown]

Ridge,


Typical plumbing solder "used to be" a 50/50 tin-lead mix.

While the "electrical solder" per the 'mil-spec' I used to work to was a 60/40 mix of tin to lead.

The flux used normally had the greatest bearing on what each was used for.

Acid fluxes for most 'general' work and rosin (non-corrosive) fluxes for electrical work.

You can use 'bailing' or 'tie' wire to hold the parts in place and once the solder starts to flow just give it a little extra twist.

You can also buy (Brownells) or make (C-clamp and hacksaw blade) a "Front Sight Soldering Fixture" that will not draw a lot of heat from the joint.

Check out Brownells and you tube.   

As mentioned above, "Soft Solder" has been and is used for gun building.

It has been used for a loooong time so if your joints are properly tinned and sweated, you should be fine.


Cheers,
Smoketown

[B.Habermehl]

When soldering a lug on the bottom barrel flat I simply use Gravity to hold it in place. Tin the lug first, draw file the barrel flat till you have clean untouched metal.  Flux the cleaned area, lay the lug in place. Heat till the solder flows, add a bit of solder if the joint looks a bit dry, and allow to cool. The biggest secret is to have clean metal surfaces. Absolutely oil and fingerprint free. BJH

[WKevinD]

I use a clamp made from metal strapping
Cluttered photo, but like this.

[WadePatton]

I have a quick question that may seem obvious to you guys, but I'm going to ask it anyway!

How do you hold the underlug in place while you solder?  My first thought is a little C clamp, but I'm wondering if that would just suck up the heat and make it harder.

Also, if I'm reading this correctly, you are just using regular plumbing solder?  Not silver?  How about electrical?  Will it matter?

Thanks.  This may be an issue for me shortly.

Silver is a much higher temp solder and isn't necessary but can be used if that's what you have.  That's what I have because bike lugs (56% Silver).  Yes, C-clamp will suck a lot of heat away unless it's tiny.  Like the banding clamp. Hose clamp can be utilized as well. Flux flux,  Go nutz.

[Ky-Flinter]

How do you hold the underlug in place while you solder? 

I found the following on the old ALR site (The Archives).....

A while back Don Getz posted a picture of a rig he used for holding a lug in place while soldering them to a round barrel.Here's a different version I made for soldering lugs on a Octagon barrel.  Tin both surfaces good before heating and the lug will pop right in place.I'm sure it would work fine for a round barrel as well if you notched the end that makes contact with the barrel.kenThose who desire to give up Freedom in order to gain Security, will not have, nor do they deserve, either one. -- Ben Franklin

***Created by
Packdog (Ken ) on 12/03/2007***

[kutter]

A small C clamp won't draw so much heat that it disrupts the soldering process. You should be heating up the bbl anyway and not the lug to get the solder to flow. 
When the bbl is hot enough to let the solder flow and sweat the two parts together, a small c-clamp will be too and it won't be a heat sink.
If you're still concerned,,you can file the dead end of the clamp to a dull narrow chisel point and the moveable end can be reduced in size. That'll reduce the heatsink effect of the clamp on the work and still provide ample stability and hold.

I use them unaltered both for this plus clamping and soldering sights, sling swivel bases and the like onto centerfire gun bbls and also use a bucket full of them when soldering the ribs back onto a SxS. If they made the process difficult or impossible I would have found out 35 or 40 years ago.

I just use non-corrosive paste flux and have never had a problem with the strength of any job.
I've re-layed ribs on countless SxS's including double rifles and never had one come back w/a problem.
Soft solder is a strong joint if both  prepared correctly and then soldered correctly.
The 'acid flux' works great but the after rust problems can be too great a risk especially on SxS re-rib jobs where you cover everything up.
Clean work, close fitting parts and don't overheat to burn the flux and you'll get a fine soft solder job.
A couple things to remember when soft soldering......
Soft solder is not a strong gap filling material,
More (heat and solder) is not better.

[oldtravler61]

That's exactly what I use. A small little pry bar from the paint department. Works like a champ

[Ridge]

Thanks for the quick an thorough answers.

[Mike Brooks]

How do you hold the underlug in place while you solder?  

I found the following on the old ALR site (The Archives).....

A while back Don Getz posted a picture of a rig he used for holding a lug in place while soldering them to a round barrel.Here's a different version I made for soldering lugs on a Octagon barrel.  Tin both surfaces good before heating and the lug will pop right in place.I'm sure it would work fine for a round barrel as well if you notched the end that makes contact with the barrel.kenThose who desire to give up Freedom in order to gain Security, will not have, nor do they deserve, either one. -- Ben Franklin

***Created by
Packdog (Ken ) on 12/03/2007***

I do this but I use a hack saw blade instead of a big honkin heat stealing piece of steel. When I was young and froggy I'd lightly dovetail lugs on to fowling gun barrels.....I'm neither young nor froggy anymore so I solder them these days.

[oldtravler61]

My little pry bar weighs about two ounces. I exercise daily so I can handle it. LOL

[alyce-james]

How about just using a hank of tie wire ?? Wrap around barrel and lug to be soldered. I've been using this method back from the 1970's. Ya all have a great week. AJ.