Screw Repair

[Flyinfool]

Everything in my welding experience would simply vaporize those screws.

Just another wild option.
Would brazing work?
you will not be able to blue it but at that small paint might hide it just fine.

I do not have any show guns, mine all get used in the field and cosmetics are way down on the list of whats important.

 

[Harry Knutz]

Thanks for the reply Harry , but I think you'll find if you dig a little deeper that M2.5 typically has a pitch of 0.45mm not 0.4mm. The search link title you come up with says that those screws are available (that's how the search engines work for commerce) but when you scroll down to the description you'll see that, in fact, they are selling standard thread screws. Check out any screw thread chart and I don't think you'll find a (0.4xM2.5) screw. Beyond that, I need a plain steel slotted screw, and the head is a custom height and diameter. I tried to "head" off (pun intended) the hardware store solution in the opening post, but i understand that, if a possibility, would certainly be the best choice. I don't believe in making any project more complicated than it should be. Thanks again


View attachment 491924

You're welcome, But as I said, I have repaired and renewed many screw heads for guns that had stripped slots by peening the screw slot and head completely closed and then rounding it off real nice with a file and emery cloth and then re-cutting the slot.

If you were to take that screw to a Gunsmith, He would do just as I just pointed out, Peen the screw, Reprofile it, Polish it and re-cut the slot. It is taught that way in Gunsmith schools also.

If I was going to weld it, I would buy the tap shown in the search results I sent you and tap a piece of say 1/4 inch alum and screw the screw into real snug and then weld it to keep the screw from getting too hot and burning out.

Here's a video from "Harry Potterfield" showing the concept.

 

[Harry Knutz]

Then after repairing the screw, You can "Fire Blue" it like seen on clock screws using a torch or use some cold blue to put a finish on it.

 

[pbiYoung]

You're welcome, But as I said, I have repaired and renewed many screw heads for guns that had stripped slots by peening the screw slot and head completely closed and then rounding it off real nice with a file and emery cloth and then re-cutting the slot.

If you were to take that screw to a Gunsmith, He would do just as I just pointed out, Peen the screw, Reprofile it, Polish it and re-cut the slot. It is taught that way in Gunsmith schools also.

If I was going to weld it, I would buy the tap shown in the search results I sent you and tap a piece of say 1/4 inch alum and screw the screw into real snug and then weld it to keep the screw from getting too hot and burning out.

Here's a video from "Harry Potterfield" showing the concept.

Thanks Harry but I have never seen a commercially available tap in M2.5 x 0.40. (0.45 & 0.35 yes but not 0.40)
Again,the results you sent the link to are not for real life screws. The title replicates what you input for searching but the results are bait & switch similarities. You have to read the actual descriptions of the items to make sure your not getting duped and then sometimes you still get the wrong item. Probably happened to many of us at one time or another. I appreciate the suggestions and input about peening, but I'm an interested in adding "bluable" metal (steel) and re-cutting or filing the slot. Here's a pic of the screw that might help clear up confusion as to what i need to do. I guess i should have put this up with original post. I'll learn someday.


Thanks again

 

[Flyinfool]

The Taps are easy. Google came up with a slew of them. I did not see any spiral point taps in this size.
Just a few.

Bolts Nuts Screws Online | TAP M2.5X0.4 Pitch Intermediate HSS

www.boltsnutsscrews.com.au

Pardon Our Interruption

LiveCart Demo | M2.5x0.4 Taper Tap

www.boltsnutsscrewsonline.com

 

[Harry Knutz]

Thanks Harry but I have never seen a commercially available tap in M2.5 x 0.40. (0.45 & 0.35 yes but not 0.40)
Again,the results you sent the link to are not for real life screws. The title replicates what you input for searching but the results are bait & switch similarities. You have to read the actual descriptions of the items to make sure your not getting duped and then sometimes you still get the wrong item. Probably happened to many of us at one time or another. I appreciate the suggestions and input about peening, but I'm an interested in adding "bluable" metal (steel) and re-cutting or filing the slot. Here's a pic of the screw that might help clear up confusion as to what i need to do. I guess i should have put this up with original post. I'll learn someday.

View attachment 491998
Thanks again

Bluing can be tricky with dissimilar metals. I would test each metal first. I see your screw is actually a special screw, I am glad you posted a pic, Now I have a better understanding. I used to do a lot of Parkerizing and was very good at it. But hot bluing is something I never did, I have used a lot of cold bluing though, And it can have splotchy results especially with 2 different metals.

Using cold blue works better if you heat the part slightly and all traces of oil have to be removed. Also make sure you boil the screw to be sure there is none of the acid left from cold bluing or the rest of the shotgun could become rusted especially if its inside of a gun cabinet or safe.

 

[pbiYoung]

The Taps are easy. Google came up with a slew of them. I did not see any spiral point taps in this size.
Just a few.

Bolts Nuts Screws Online | TAP M2.5X0.4 Pitch Intermediate HSS

www.boltsnutsscrews.com.au

Pardon Our Interruption

LiveCart Demo | M2.5x0.4 Taper Tap

www.boltsnutsscrewsonline.com

Bluing can be tricky with dissimilar metals. I would test each metal first. I see your screw is actually a special screw, I am glad you posted a pic, Now I have a better understanding. I used to do a lot of Parkerizing and was very good at it. But hot bluing is something I never did, I have used a lot of cold bluing though, And it can have splotchy results especially with 2 different metals.

Using cold blue works better if you heat the part slightly and all traces of oil have to be removed. Also make sure you boil the screw to be sure there is none of the acid left from cold bluing or the rest of the shotgun could become rusted especially if its inside of a gun cabinet or safe.

 

[pbiYoung]

Bluing can be tricky with dissimilar metals. I would test each metal first. I see your screw is actually a special screw, I am glad you posted a pic, Now I have a better understanding. I used to do a lot of Parkerizing and was very good at it. But hot bluing is something I never did, I have used a lot of cold bluing though, And it can have splotchy results especially with 2 different metals.

Using cold blue works better if you heat the part slightly and all traces of oil have to be removed. Also make sure you boil the screw to be sure there is none of the acid left from cold bluing or the rest of the shotgun could become rusted especially if its inside of a gun cabinet or safe.

That's good advice there Harry. I have done a fair amount of cold bluing and rust bluing and given its size I'll be okay with cold method. Thanks for the input.

 

[pbiYoung]

The Taps are easy. Google came up with a slew of them. I did not see any spiral point taps in this size.
Just a few.

Bolts Nuts Screws Online | TAP M2.5X0.4 Pitch Intermediate HSS

www.boltsnutsscrews.com.au

Pardon Our Interruption

LiveCart Demo | M2.5x0.4 Taper Tap

www.boltsnutsscrewsonline.com

Keep Googling. Two of those links look like some fake website in Australia and you’ll be hard pressed to get the listed phone number to work. The MSC link is to a $200 thread mill (not a tap), but thanks anyway

 

[Alexander McGilton]

Are you absolutely sure it is an M2.5x.4? Could it otherwise be an M2.3x.4 or an M2.5x.45?

Both alternatives are more common for screws , taps and dies