need help with lock placement!!

[coutios]

  bgf is spot on... you will never get the lock in the proper location if you can not see your touch hole mark and the space between the bottom of the barrel and ram rod hole...  Don't be timid about getting rid of extra wood....

By the way Bill nice photos... I need to stop in and say hello..

Regards
Dave

[BillPac]

Thanks Dave; next class is June 18th.

[uplandhunter]

Well I have commited myself.

[A.Merrill]

    Your not committed yet, not until the lock plate is inletted. Look at the other pic's, the fence on the flash pan should line up with the rear of the barrel and it still looks a little high on the side flat. Slow down, get it right or you will regret it later. From looking at the pic's it needs to go forward about an 1/8in. What do you guys think?    Good Luck    AL

[Don Getz]

Merrill......you are giving him some bad information.   Don't worry about where the fence of the lock falls, it does not have
to be in alignment with the end of the barrel.   You should first determine the length of the breechplug threads, then
add  1/2 the diameter of the touch hole liner......this is where the touchhole will be.   Align your lock so that this is in the
center of the pan....horizontally...............Don

[uplandhunter]

that is what I have done. thanks for all of the help. I am sure this lock will not be in perfect, but this is my first solo build so I am sure I will learn a lot.

[BillPac]

Upland
The vertical line that comes down over the side flat is the line locating your touch hole NOT the breech correct?  If so you seem to be OK front to back to my eye.  I believe you are still too high on the side flat but since you have the bolster cut in you can live with it as you suggested or that area is hidden by the cock and you could patch a piece in and lower it.  It is much better than yesterday when you were fighting it so hard.
BillP

[rich pierce]

I think you're looking much better now. 

[Dphariss]

Lots of pre-carves are less than desirable in one way or another..
You could use a smaller lock OR put the vent below center line. This works fine and also moves the mainspring inlet farther from the barrel.
I hate having the fence very far in front of the breech of the barrel (I don't care who did it in 1775) but its almost a given with precarved stocks. These are generally set up for barrels that are tapped deeper for the breech plug  than they need to be. On large barrels with relatively small bores can have a .100 hole where the drill just touches the breech face. and the liner seated against a shoulder. But large bores and thin barrel walls do not allow this.
Precarves, generally speaking are made to work for the lowest common denominator. The unskilled maker can make them work and gain experience. They generally just irritate the experienced builder in one way or another. Unless he makes a career of using precarves..

Dan

[A.Merrill]

    Don, your right, the pan should line up with the touch hole. But he had already started to inlet and it looked like in the pic. the pan was to far back on the barrel and I thought if it was moved forward 1/8 in. it would be closer to where it should be. I have never had wood showing between the fence an the rear of the barrel. Sorry, I was just trying to get him to understand where it should be.    AL

[Dr. Tim-Boone]

 The fence on this lock is further forward....the only way to move it back would have been to cut into the breech plug..... doesn't meet my idea of aesthetically pleasing but it is functional and nobody has ever made a comment about it.. 


This is the same lock you are using and it lines up nicely when the touch hole is done as Don described!! 


Here is the top view


I am learning that every build/lock and breech combination requires pre-planning and the locks are often different  in distance from touch hole to fence and some have shorter bolsters than others... they are not all interchangeable in those dimensions let alone in lock plate size and shape.

[A.Merrill]

    Page 2, the last pic Uplandhunter posted. It might be the pic, or there is more wood to remove, but the fence is not on the barrel at all. Dose anybody else see this???   HELP ME     AL

[Dr. Tim-Boone]

It looks to me like he has not inlet it fully for the bolster  or the fence to be on the barrel yet.....I hope.

[D. Taylor Sapergia]

He's only let in the bolster so there's wood yet to come out of there.  It looks like everything will work out ok, but I would have like to see the forward end of the plate dropped about 1/16" more.  Also, I'd like to have seen more than half of the side flat exposed before he got this far.  that would have dropped the lock plate to a better position.  Still, I think it'll be fine.

[D. Taylor Sapergia]

Here's an example of that lock 'let into a precarve - namely Chambers' Mark Silver Virginia rifle, but the app is the same.  Note that more than half of the barrel is exposed, and that the vent is also below the centre line of that flat.

[uplandhunter]

I am here now.

[Jerry V Lape]

Dan Phariss,  The discussion about fence placement gave me pause.  If your breech plug is .50" and the 5/16" diameter white lightening vent liner is used that adds another .156" to vent location.  I measured the two locks I have here, a Ditchburn and a Chambers Golden Age for the distance from center of pan to back of fence.  They are strangely identical at .437".  Therefore the fence is going to fall .119" inch forward of the end of the barrel.  But even if I were to use a simple drilled vent w/o liner the fence would never be at the rear of the barrel.  So the question is what in your opinion is an acceptable amount the fence could be forward and be acceptable? 

Dr. Boone, you showed two different locks in your photos.  The one has the fence substantially forward of the end of the barrel and the other does not.  That second lock obviously has much greater space from the center line of the pan to the backside of the fence.  I have wondered why, since the use of vent liners is so popular, why lock makers haven't lengthened this dimension in order to accommodate fence and touchhole placement. 

[bgf]

Jerry,
Your math is pretty much the same as mine.  It depends only on the depth of the breechplug and the length of the lock from pan center to back of fence.  There is a little wiggle room in that that you could move the lock lower (or tilt it back slightly) and increase that distance effectively, but there is a limit there as well (what about thinner barrels, for example, there's little room to begin with).  Where did the fence aligned with breech "rule" arise -- I'm guessing some pamphlet printed in the 70's?  In the lock panel thread, Dr. Tim showed a couple of originals and two contemporaries that broke that rule, and I've seen many more.  The only reason I care is that short of everyone making a custom breechplug (obvious problems), we would have to shorten the breech plugs substantially, which strikes me as also fraught with some peril (who knows the safe minimum) when using locks that are short between pan and fence.  Maybe this is something the top pros can keep as their discriminator, if they all agree on it.

[Dr. Tim-Boone]

  Actually Hugh Toenjes makes a breechplug with a counterbore that allows you to make the touch hole through the wall of the barrel and the wall of the plug.....Where there is a will there is a way.  

[A.Merrill]

    Didn't most original guns have breech plugs that were shorter than what we use today? I can see were a barrel company does not want to get sued, but with better an stronger steel we have today you would think we could get by with shorter plugs say maybe 3/8in. long. That would help the fence line up with the end of the barrel.    AL

[uplandhunter]

I am here now.

[bgf]

    Didn't most original guns have breech plugs that were shorter than what we use today? I can see were a barrel company does not want to get sued, but with better an stronger steel we have today you would think we could get by with shorter plugs say maybe 3/8in. long. That would help the fence line up with the end of the barrel.    AL

I can't say, but there are plenty where the fence is ahead of the breech.  I would also argue that they were rarely shooting the charges we consider necessary, so they might have been fine, if they did use thinner breech plug?  3/8" or less might be fine now, but if I do it and it blows a pointy tang back through my head, then it is likely I'll be remembered as a stupid redneck, and no one will ever notice that the fence lined up with the breech:).  I didn't mean to come across so strongly, as it just isn't something that seems consequential to me, and is perhaps a little arbitrary.  Granted, different strokes for different folks.  Aren't there some truly great original pieces that ignore this rule?  I'll ask, because some people may not think my choice of originals qualify.  What defines this standard?

[D. Taylor Sapergia]

I am here now.

I see that you have the plate in right up to the bevel.  Now you have to inlet it until the bolster touches the barrel's side flat over it's whole length.  That will take the plate itself down below the original precarved surface.   When you dress off the side panel down to the bevel again - it must stand proud of the panel - you will suddenly have a lot more panel to sculpt.
As I said, I think things are going fine.

[Jim Kibler]

I am here now.

It seems there is a lot of wood underneath the lock.  If a good deal of this can be removed in the shaping process, the looks of the stock and lock placement will improve.  It seems the wrist turns downward pretty dramaticaly along the bottom line as well.   If this can be made to transition a little more gradually, things should improve.  It's hard to be sure of any of this based on the the small area of the photos, but it's something to consider. 

[greybeard]

    Didn't most original guns have breech plugs that were shorter than what we use today? I can see were a barrel company does not want to get sued, but with better an stronger steel we have today you would think we could get by with shorter plugs say maybe 3/8in. long. That would help the fence line up with the end of the barrel.    AL
[/quote
Many years ago I read in muzzle blast a test done by "The Right Honorable Bill Large" where he tested threads by firing a service load. then turned one thread off the plug and equi ammount off the back of the barrel. He repeated this untill the plug blew out. He was down to 1 1/2 threads when it let go.
   
This statement is in no way a recomendation that you shorten your plug. Just an observation.
     Bob