Help with triggerguard shaping

[cwilson]

I tried replacing the triggerguard on my Southern Mountain rifle that was broke and heated up the new one with a propane torch to bend it to the right curve and managed to snap it into, going to try an braze it to fix it but my question is what technique do you guys use to shape the cast triggerguards?
Chris

[northmn]

Brass anneals by heating red hot and quenching steel by heating red hot (non magnetic state) and slow cooling.  Don't get too critical on my terms.  So a cast brass needs to be annealed and then bent.  Sometimes more than once or a little at a time.  Steel should be bent while heating.  Sometimes a cold bend can be made if not too drastic and over a longer piece.  Best way to break steel or brass is to hold them such that you get pivot where the bend is stopped.  Also you have to keep the heat up while bending.  I ahd an old Dixie cast iron triggerguard that would not bend even when doing all this.  Wnded up brasing it in one spot and then the *&**&^ thing melted in another while heating it to avoid another break.  The newer investment cast units will bend a little easier.

DP

[JCKelly]

I'd like to comment on brass castings. The most ductile are those parts sold by Reaves Goehring. Just bend them, that's it. No need for anneal first.

It is common practice to add a percent or two of lead to brass when making a casting. Makes the casting sounder. Some years ago California got all bent out of shape about this & forbade the use of this lead in plumbing fixtures, e.g. faucets.

If you choose to anneal brass it is best to quench it, not slow cool. This is so that various Nasties, such as the lead, are more evenly distributed. Slow cooling may allow The Nasties to all congregate together & make the thing brittle.

To bend brass, do it at room temperature. If you heat brass to bend it, it will crumble. Then you need to get a new casting. 

The metallurgical explanation is that if you melt the little particles of lead - which are present as lead itself - that molten lead quickly goes to the grain boundaries & the whole part, while it is hot, has the strength of molten lead. Which is to say it will crumble.

The practical explanation is that many hot brass castings will break when you try to bend them.

Cast iron triggerguards would be malleable iron, which ain't nearly so malleable as the name suggests. I'd bend them gently while they are red hot, and cool slowly.

[T*O*F]

I.  A propane torch isn't hot enough to distribute the heat.
2.  You have to heat where you want to bend red hot, and "at least" one inch on either side of that location.  If you try to do this with a propane torch, one end will always be cooling while you are heating the other end.
3.  Use oxy/acetyl, oxy/propane, or Mapp torches.
4.  There reason they break is becaus you are spot heating.

[Dennis Glazener]

The most ductile are those parts sold by Reaves Goehring. Just bend them, that's it. No need for anneal first.

Not to be argumentative but my investment cast brass TG & BP can be as easily bent as Reaves. I have seen others just as soft. I just depends on the brass alloy used in casting them.

My steel trigger guards can be bent cold, never had a need to check the BP's but I am sure they too can be easily bent. Again, its the alloy used to cast them.
Dennis

[T*O*F]

A lot of the older steel castings are still floating around and it depends on where you get them.  The ones Dixie Gun Works used to sell were harder than Dick's hatband and would snap if you looked at them crossways, let alone try to bend them.  This is probably true of any of the sand cast ones.  They seemed to have a lot of inclusios in them.  If you buy parts off eBay you're likely to get one.

[billd]

I've never seen cast iron or mallaeble iron TGs or BPs.  All the ones I have used are carbon steel.    Heat to red and bend while red.

I've never used Dennis's brass hardware but if it's anything like Dave Kecks you don't have to anneal it.   Reeves are sand cast.  I know he uses a soft alloy but I don't know if it's the same as Dennis's or Dave's.  Theirs are investment cast, or lost wax.



Bill

[JCKelly]

Looked on Gillespie site, nice trigger guard. Have had no experience with them, glad to hear that they, also, are ductile. I have an odd assortment gathered over the decades, don't recall source of each.
 
Where does one get guards from Dave Keck?

On those rare occasions these days when I use brass hardware I am inclined to need to bend it around a bit. Debating whether to put a Real trigger guard on my Pedersoli "Kentucky" pistol, once I remove enough wood that my short fingers can reach the trigger.

[billd]

http://www.knobmountainmuzzleloading.com/

Dave Keck's site.