AmericanLongRifles Forums

General discussion => Gun Building => Topic started by: Uncle Alvah on December 07, 2017, 07:27:34 PM

Title: Through hole drilling
Post by: Uncle Alvah on December 07, 2017, 07:27:34 PM
On a single screw lockplate, at what point should the through hole for the backplate be drilled?
Title: Re: Through hole drilling
Post by: D. Taylor Sapergia on December 07, 2017, 07:48:13 PM
Are you asking "when" should it be drilled, or "where"?
Title: Re: Through hole drilling
Post by: David Rase on December 07, 2017, 10:35:12 PM
I like to inlet my lock plate about to about 90% depth and then install my lock bolt(s).  I then use the lock bolts to draw up the lock plate for final inletting.  I started doing this because a couple of times after I had inlet and seated the lock plate full depth, I found that snugging down the lock bolts caused me to lose my metal to wood fit on the underside of the lower half of the lock.  I think this condition was due to removing too much wood during seating of the lock plate with a mallet.
David     
Title: Re: Through hole drilling
Post by: Dennis Glazener on December 07, 2017, 11:17:04 PM
I do the same as David but when making SMR rifles I always try to move the lock bolt/hole away from the breech/stock juncture. If you don't and plan to use a larger sideplate/washer you don't want it to be too close to the top edge of the stock (see photo below), ask me how I know! I move the lock bolt hole as far back and as low as I can go and still be in the lock bolster.
Dennis
(https://americanlongrifles.org/forum/proxy.php?request=http%3A%2F%2Fpreview.ibb.co%2FdVmnXw%2Flock_bolt.jpg&hash=50b7436d37254749c6165b931d45e92beedb341b) (http://ibb.co/fvdO5G)
Title: Re: Through hole drilling
Post by: Uncle Alvah on December 07, 2017, 11:57:58 PM
Are you asking "when" should it be drilled, or "where"?


When
Title: Re: Through hole drilling
Post by: D. Taylor Sapergia on December 08, 2017, 04:54:51 AM
The late Hawken rifle is a good example of the single lock bolt system.  I do a similar technique to David and Dennis in that I inlet the lock - it can only go in one place - until it is almost bottomed.  I then tap drill the bolt hole in the REARMOST AND LOWEST POINT in the thick plate bolster.  On a Hawken, it's a 10 x 32 cheese head machine screw.  Before I thread it, and running the drill bit through the plate's hole, I set up the rifle with the lock in its mortise square with the world in a drill press vise, and drill right through the stock out the other side with the tap drill.  Then I pass a clearance drill through that hole, removing the lock plate first.  I put the lock back into it's mortise and thread the plate from the offside.  Now the lock retaining screw can be used to pull the lock into its mortise more solidly and squarely, and the finishing inletting can be done.  When the lock bolster is seated firmly and evenly against the side flat of the barrel, I'm done.
Title: Re: Through hole drilling
Post by: Majorjoel on December 08, 2017, 10:00:13 AM
I do exactly the same as you Taylor but have found it hard to find a good tap that is long enough for the job when using a wide barrel.   All of the hardware store taps around here are too short to make a complete pass through.  So on those occasions, after getting the threads started from the side plate side, I remove the lock plate and finish tapping by carefully finding the starting threads.

A painful extra step that would be avoided if I could find a good set of longer taps!
Title: Re: Through hole drilling
Post by: SingleMalt on December 08, 2017, 12:48:37 PM
I like to inlet my lock plate about to about 90% depth and then install my lock bolt(s).  I then use the lock bolts to draw up the lock plate for final inletting.  I started doing this because a couple of times after I had inlet and seated the lock plate full depth, I found that snugging down the lock bolts caused me to lose my metal to wood fit on the underside of the lower half of the lock.  I think this condition was due to removing too much wood during seating of the lock plate with a mallet.
David   

That's an excellent idea, David.  I'm going to try it on my next build.
Title: Re: Through hole drilling
Post by: RL on December 08, 2017, 05:00:52 PM
I bought the 10-32 drill/tap combo bit from McMaster-Carr. It worked. I also epoxy a 10-32 spacer from side plate to lock to keep the plate from kicking out at the bottom. I guess Sam Hawken didn't do this but I've spent the last 23 years repairing broken mechanical parts in my day job.
Title: Re: Through hole drilling
Post by: Bob Roller on December 08, 2017, 05:12:30 PM
I do exactly the same as you Taylor but have found it hard to find a good tap that is long enough for the job when using a wide barrel.   All of the hardware store taps around here are too short to make a complete pass through.  So on those occasions, after getting the threads started from the side plate side, I remove the lock plate and finish tapping by carefully finding the starting threads.

A painful extra step that would be avoided if I could find a good set of longer taps!

Look in any industrial supply catalog for "PULLEY TAPS".They are longer
and not that expensive.

Taylor,WHAT is a "cheese head"screw??

Bob Roller
Title: Re: Through hole drilling
Post by: 45-110 on December 08, 2017, 05:20:34 PM
cheese head......just a round flat top head machine screw, non counter sink.
kw
Title: Re: Through hole drilling
Post by: D. Taylor Sapergia on December 08, 2017, 07:32:12 PM
Sometimes called "Filister Head".
Title: Re: Through hole drilling
Post by: P.W.Berkuta on December 08, 2017, 08:03:47 PM
I do mine a bit different. I center punch the bolster in the rear bottom corner then drill with the tap drill for the screw that I am going to use. I inlet my lock to full depth or slightly below to allow for final sanding. With lock in its mortise I drill through the stock using a drill press then remove the lock and drill the stock with a clearance drill replace the lock and tap the plate from the non-lock side - never has a misalignment issue with this method.
Title: Re: Through hole drilling
Post by: Turtle on December 09, 2017, 12:28:51 AM
 If I take the tap out of the tap wrench after going as far as I can, I can usually tap it the rest of the way with small vise grips. If I can't I push the lockplate out with the tap still in it and finish tapping out of the stock.