Slip joint tangs

[Nsewell]

How much do I need to round the corners on the half stop to prevent chewing up the spring? Any pics

 

[Randy3000]

Here is one i am in the middle of now. I barely round the corner. I mean, half used belt and lay the blade on the table and lightly touch to the belt when turning a 45 degree angle. I do not radius it a full 90 degree. I make no claim that i am doing it right, but it doesnt chew up the spring. How big is your pivot hole?

 

[Nsewell]

1/8. that's the only size 416 pinstock i had

 

[Randy3000]

I am trying to understand how the tang can chew up the spring. You have roughly 1/8" meat around the pivot hole, which is about right i think depending on the style of blade and handle. I usually do a 3/32" pivot pin and anywhere from 3/32" to 1/8" meat around the tang. So i dont think you have excessive force in the tang area. Do you have a hard edge on the tang corners now? Is it a real nail breaker?

 

[Don Hanson III]

Corners can be square, but should not be sharp.

 

[Nsewell]

The pull is a just about right maybe a little strong. The first few times I open and closed i didn't oil it and it left some scratches on the spring. I still have a tiny bit to remove to get it flush but just wanted to know if I need to round it before I went to far. Thanks!

 

[Randy3000]

Getting the contacting surfaces as square as possible is important. Lay the spring a blade flat up against each other and if you can see daylight on one side then you can adjust. I get it close with a square on the grinder, but always have to bump the table a bit to get it perfect. I can normally get it dialed in perfectly while i am fitting.

Anytime i adjust the tang and it sharpens the corners, i will reradius it a tad like i mentioned. After getting the blade mostly made and fitted close (within 0.005") with 220 grit, i will heat treat the blade. After i get the handle scales made, i will preassemble and do a final fit with up to 1000 grit, then open and close the blade a few dozen times. This will establish a wear pattern. Ideally the wear pattern will be on spring and tang along the full thickness. Then i do a final deburr (dont take too much off the edge, just run a small file across it a few times) to take off any galling that occured.

This works for me.

 

[Nsewell]

I rounded the corners a little more and sanded it to 400 grit and it really smoothed out

 

[autogateman]

I barely knock off the corners, as if you hit it on sandpaper. Just enough to not be sharp like don said. Then polish the walk area of the spring and polish the tang.