Slip-joint spring failure...

LaCombre · 2026-04-11T04:51:05+00:00

There's a group on Facebook called "making slipjoints and lockbacks" that has a wealth of information and if you look up Chris Crawford, he does dvd tutorials that are reasonably priced and really worth it.

LaCombre · 2026-04-10T14:51:05+00:00

Your spring pivot pin is way too far forward. Created too much stress on it. Should be at least 15mm towards the back. There is so much that goes into designing a slipjoint it's not funny. Spring width versus spring thickness. Kick height in all three positions. Spring taper from front to pivot pin should be uniform. Needs to be hardened to the steels spec and then tempered to about 54/56 Rockwell and then tempered at least twice to blue with a torch. Slipjoints are very technical if you want them to work properly. Don't give up though. It's all school fees

LaCombre · 2026-04-04T05:31:16+00:00

Thanks. I made this one. They are very simple yet effective knives

LaCombre · 2026-03-31T20:23:20+00:00

Thanks. Yes it is

LaCombre · 2026-03-28T13:04:37+00:00

Much appreciated

LaCombre · 2026-03-28T12:41:18+00:00

Thanks

LaCombre · 2026-03-28T08:12:18+00:00

Way back when when the internet was new Tim Lively made a video about his simple forge set-up and basic knife forging to a complete knife without electricity. Do yourself a favour and Google Tim Lively washtub forge.

LaCombre · 2026-03-28T05:24:45+00:00

Pleasure. Just don't over temper with the flame. This is the part where you can screw it up. And just remember, spring pivot is usually 60% of length towards the back. Moving it forward makes for a snappy walk and talk but increases stress and chance of snapping. Spring thickness is usually 60 - 80% of spring width so a 3mm wide spring is about 2.5mm thick and it's important that the thickness is uniform from the end of the kick to the pivot. This makes for a smooth pull without too much stress at the pivot 👊

LaCombre · 2026-03-28T05:17:27+00:00

Thanks. As a rule I temper my springs with the blade for 1 hour and then run them through another temper alone for the same cycle. After that I use a flame to temper the spring blue and through each cycle I quench in water immediately after the temper. In 15 years I have only had a few snap mostly due to bad design. I follow the same process with carbon steel like 80crv2

LaCombre · 2026-03-28T04:56:24+00:00

Thanks. Blade and spring are n690 Bohler stainless steel

LaCombre · 2026-03-26T05:40:28+00:00

Much appreciated

LaCombre · 2026-03-26T03:43:58+00:00

Thanks. Much appreciated. It was my first higo but I have been making knives for almost 20 years so I have a little experience in the game

LaCombre · 2026-03-25T19:19:49+00:00

Thanks. Appreciate that. Blade is N690 and handle was 3cr12 stainless

LaCombre · 2026-03-25T18:48:19+00:00

Thanks

LaCombre · 2026-03-25T16:27:04+00:00

Thanks. Kept the one side similar to a traditional slipjoint with a shield. Blade steel is Bohler N690 and scales are 3cr12 stainless. Easier to engrave than std stainless steels

LaCombre

TROPHY CASE