Messed up the tangbolt hole.

[Rolf]

I messed up drilling the tang bolt hole in the rifle I'm building.. It should have been chanted more towards the butt plate. I tried to fix it by tilting the camfer for the bolt head. Did not work.

1. Is there a simple way to fix this, or to I have to weld the hole shut and re-drill?
2. If I weld the tang, should I weld the hole in the triggerplate?

best regards
Rolf

[smart dog]

Hi Rolf,
First, can the triggerplate be moved forward a little or could you make a longer one with more metal in front of the trigger?  Then fill and redrill the hole in the stock at the correct angle.  If you cannot do that, can the tang be filed down to reduce the size of the countersink?  Then can you forge the head of the bolt such that it is on an angle.  I have an original English shotgun on which the makers did that very successfully.

dave

[D. Taylor Sapergia]

Good comments Dave.  And I'd be making a new tang screw with a larger head.  Also, the taper of the head must match the taper of the countersink.  To be certain, countersink a steel plate and forge the screw head into the countersink.  Then use the same countersink on your tang so the screw will be a perfect match.  This advice may not be of use in this case, but a larger headed screw might diminish the effect of the error.  Ask me how I came to this...been there.

[kaintuck]

I did a re-weld and re-drill......works best.

[Acer Saccharum]

The bolt shank MUST be perpendicular to the tang for the countersink to be even.

[Jim Kibler]

If you counterbore rather than coutnersink, things will be a little more forgiving.  The top of the screw can be tweaked slightly to match the tang shape.

[Acer Saccharum]

Jim, that's a good fix for this situation.

[D. Taylor Sapergia]

Jim, do you mean with a  lathe centre drill?

[Acer Saccharum]

A squared pocket counterbore for a cheese head screw.  http://newtowoodworking.com/tag/counterbore/

[David Rase]

Can you file the tang profile between the breech and the head of the tang bolt to put the plain of the tang more perpendicular to the tang bolt without affecting the shape of the wrist too much?  I have done that to correct slight deviations in alignment.  You could also straighten the same area and reinlet it a bit deeper to flatten things out.
David

[chubby]

Rolf, you could also take a 8/32 lock bolt and chuck in a lathe or drill press and file down the back side to match your hole have done that it works out ok!!

[John C IND]

The tang or shank of the countersink has to follow the same line as the centerline of the drilled hole.
If you can set it up in a drill press or a mill vise, over the centerline of the hole, AND parallel to it, it should work.
That's the best way to fix it without welding.
That is, unless you can fabricate a countersink with a long pilot to guide it.
Don't ask me how I know...
Good luck with it,
John

[Tom Currie]

Rolf, Somehow knowing someone with your skill level can make the same mistakes as I do makes me feel better. I had mine all welded over.

[D. Taylor Sapergia]

Tom, I'm missing something with regards to the courterbore...a flat bottomed hole??

[Acer Saccharum]

Screw placement is a tricky thing.

The screw shank, ideally should be parallel to the radial line of the tang curve, as in #1.

If you end up with #2, which I think you have, Rolf, the counter sink style screw head will have reveal problems on the downhill side. If you file the screw head to fit, it will look egg shaped.

If you use a cap screw with a domed head, you can use the #3 illustration, and file the screw head to look right with the curve of the tang.



I think this is what Jim Kibler is suggesting. The type of screw in #3 is much more forgiving that the flathead type of screw.

[Frenchy]

I'd be making a new tang screw with a larger head.

I'm with you on this. When I countersink something and get it at the wrong angle, I make a new screw with a large head. I coat the inside of the countersink with felt pen.
Put the screw in and take it out. Where the ink was rubbed off is where the bottom of your screw head hits. I tilt the countersink and cut it a bit deeper. Sort of like taking off the hi spots when inletting. When it hits properly, I file the top of the head so it is a concentric dome (more or less) above the tang. When it is un-screwed it looks as though the head has been forged into the countersink because it is so crooked.
In Acer's picture #2, I would just re-file the head of the screw and make sure that the screw slot was done correctly.

[smart dog]

Hi,
Acer and Jim, a counterbore would be good except Rolf now would have a very large screw head given the countersink he created.  That might be OK (I cannot really tell from the angle of the photo) but I think he needs to consider filing off some of the top of the tang to reduce the size of the countersink.  He may not have extra metal to do that depending on the gun's profile.

dave

[Jim Kibler]

If you don't have a welder available here's an option.  Drill / file the hole out larger in the right spot, silver braze in a rod for a plug and then engrave a line in the joint to hide it.

[Dphariss]

Counterbore.
This fits the head of a socket head cap screw.

http://www.mscdirect.com/product/08272783?fromRR=Y
Searching through catalogs will turn up various sizes of counter bores. Can be used to cut nipple seats (may have to make a bushing for the pilot).  Can be used to make a flat shoulder to seat vent liners too as well. But this usually requires making ones own liners.
These are very useful tools.

Me? I would likely make a new trigger plate, plug the hole in the wood and with the relocated hole in the new trigger plate change the angle of the screw so the screw shank was 90 degrees to the tang.
Dan