TIG welding bad scope mounting holes

[copperlake]

I've developed a way to TIG weld poorly placed scope mounting holes that is (I think) perhaps a little different and offers the 'casual' welder a way to accomplish it without too much stress. First off I have to say that the word TIG is the a magical thing that we all read about on the web. After MIG and stick welding, only oxy-fuel imparts more heat into the effort than TIG, especially when talking about short welds.

Here is a 96 Swedish mauser that was seriously funkified.


Attachment 255509


Attachment 255510

The receiver holes were at an angle and the aft one bumped the locking lug boss along with being rotated off center and pointing towards Bethlehem. The aft ones were scattershot. More or less a junk action. I have several. Filling a hole with weld to make sure there is enough material to re-drill for threads to take can be a problem. If the holes are close to being on center then the weld needs to pretty much fill the void. That is what creates a problem. In order to do so, one needs to expand it it order to fill it. I could go on about this but what I offer is a way to avoid that so I'll hope over that. Amusingly, the duplex nails showing the angled drilling is the (my) solution to the problem.

More to come as it seems I have figure out how to dump pics to add more...

[cub45]

I've used tig to fix those holes, I put flush screws in holes and tig over them.

[elk hunter]

I've TIG welded some holes in receivers but I've also cleaned the holes and used loctite to hold plug screws then re-drilled and tapped. This works best if the holes can be moved to leave most of the plug screw intact. I've saved some stripped holes by drilling and tapping oversize then plugging using loctite and re-drilling and tapping to the smaller, original size.

[waksupi]

I've TIG welded some holes in receivers but I've also cleaned the holes and used loctite to hold plug screws then re-drilled and tapped. This works best if the holes can be moved to leave most of the plug screw intact. I've saved some stripped holes by drilling and tapping oversize then plugging using loctite and re-drilling and tapping to the smaller, original size.

Same here. Easy way to go about it. If the plugs are installed then the bridge blueprinted as it should be, they disappear. Even on custom actions I have never seen one that didn't need blueprinting.

[John Taylor]

I fill lots of holes in rear bridges with tig but try to stay away from the locking lug area, don't want to mess with the heat treat there. Most of the time I will drill and tap for a bigger screw and then drill into the plug screw and tap it. I get a couple guns a month that have the screw holes messed up, sometime by the owner trying to install a scope with a hand drill.

[justashooter]

I fill lots of holes in rear bridges with tig but try to stay away from the locking lug area, don't want to mess with the heat treat there.

as a welding engineer/inspector i cannot agree more.

[copperlake]

To continue: I'm not suggesting that what I'm doing is the best way to fill holes but, I believe, that it has advantages. AND I'm only talking mausers here, actions that are low to medium carbon steel that are cased in areas for wear. I am not a Jerry K. kinda guy that believes that if your 98 gets too close the the campfire on a moose hunt it then needs to be sent off to Blanchard's.

I take a duplex 8d nail and cut off the top head leaving a little extra above the second head. Why duplex? For to have a little more material on top. I haven't tied a common but box nails have a thin head. They cost me 1.29 per LB and are mild steel. They are cut off at the appropriate length for depth, the ones to fill the threaded areas, of course, being short of the thread bottom:

Attachment 255574

A drill near the size of the nailhead is used to make a small countersink:

Attachment 255575

NOTE: The bad holes were enlarged with a number drill slightly smaller than the nail diameter so that these 'studs' can be hammered in making a friction fit. And now the fun part for all you maybe tig weldors, and actually one of my points. Strike the arc on top of the nail and within 2-3 seconds it forms a ball. Then, only orbiting around this ball very shortly one sees it slump a bit and joint with the parent metal. This takes all of 10-12 seconds. STOP. Do not wander over to the parent material, period! Bow compressed air over the assembly for 30-45 seconds and after that, one can put bare fingers on it. Now we have a proud pimple that is attached to the parent material. But! someone needs to help me figure out how to delete pics because I'm over the 10mb limit and can't figure out how to do it in order to continue!

[abunaitoo]

Just found out how to delete pictures/attachments from my profile.
Go to the box at the top right of the page.
It has you name in it.
Click on the small arrow next to your name.
Click on "inbox"
On the left side of the page, starts with My Messages, Scroll down until you reach the "Settings" box.
At the bottom of the box, look for "attachments"
Click on it to open.
In that page you will see all your pictures.
Go through them and delete those that are not relevant to you, or us.
Hope this helps.

[copperlake]

abu, thanks so much! I tried every way. Not very intuitive to say the least.

To continue: here is the pimple that has no surface disturbance of the parent material:


Attachment 255646

So on so forth holes are filled one at time and the result after filing and sanding:

Attachment 255648

A little Birchwood, pick the altered one:

Attachment 255649

The advantages of this way:

1) The least amount of heat put to the action

2) No disturbance to the parent material - no ripples - making for easy finishing

3) No other threads or (potentially) hardened screws to deal with

The disadvantages of this way:

1) Mild steel studs may not take hot blue

[abunaitoo]

Looks good

[757fan]

I am not sure anyone is still monitoring this thread or not but have a question related to the topic. Just had an a barreled action drilled and tapped and when I got it back I saw that it was drilled and tapped further back than I want even though I marked the with a center punched the forward and aft holes of a one piece scope base. My biggest concern is rear hole on the forward part of the receive is over the top lug by 2/3 of the screw hole, can this tig welded and the receiver made safe?

[Cap'n Morgan]

My biggest concern is rear hole on the forward part of the receive is over the top lug by 2/3 of the screw hole, can this tig welded and the receiver made safe?

Just let it be. Even with half a hole partway down the lug face, the action is in no way unsafe.

[Alferd Packer]

Surgical tig welding to be sure.
Thanks for sharing.I was a stick and gas welder for years. Always wanted to tig and worked around pipefitters tig weldors.Wanted to learn for the very thing you are using it for. I understood your explanation. Again, thanks for sharing your method.

[William Yanda]

"Here is a 96 Swedish mauser that was seriously funkified."

How does that compare to badly bubba'd?

[samari46]

Kinda hate to tell you this but all your attachments didn't work. Tried every one all came back invalid attachments. Frank

[largom]

Attachments would not work for me either.

[Streetwalker]

Same here. Verbal part of posts are very interesting, though.

[John Taylor]

Got in an older Remington 722 that someone use an ark welder on the rear bridge. It shrunk it so much that the bolt would not fit so they forced it in and cracked the rear bridge. While tig welding can be used on guns I have never seen a use for an ark ( stick) welder on guns.