Making a Button lock folder

[Don Robinson]

This course will teach you how to make my version of a button lock folding knife from start to finish.

NOTE: This design doesn't spring open suddenly like a switchblade. It does not open with a torsion spring. The opening spring is made of titanium and the spring force can be adjusted by bending the spring to suit.

A highly detailed CAD design for the project knife is included in the cost of the course.

This project requires a high skill level and should not be attempted unless you have previous experience making other types of knives.

Required equipment:

Vertical milling machine ( an accurate bench mill will work)
Metal cutting band saw
Drill press
Knifemaker's belt grinder
Small metal lathe

Miscellaneous hand tools, such as HSS drills, spiral point taps, 82 degree countersinks, Torx screw #######, files, T-handle tap wrench, tapping fluid, sandpaper, etc.

Suggested additional equipment:

Bead blaster
anodizer
Buffer


Bill of material:

.030 to .060" thick 6AL/4V titanium for the actuating spring

3/32" thick 6AL/4V titanium for the liners and bolsters

Blank pocket clip if desired, preferably titanium

Your choice of blade steel, 1/8" thick x at least 1 1/4" wide and preferably flat ground. The back spacer will also be made of the same material.

3/16" and 1/8" diameter straight pivot pins with internal threads

A few .016" diameter wire x .180" O.D. x 1/4" to 3/8" long coil compression springs made of stainless steel MSC part # 03307774

A few .016" dia. wire x .180 O.D. x 1/4" or 3/8" long coil compression springs made from music wire MSC part # 17006810238

Note about these springs!:Only one of the two types of springs called for above will be used in the final assembly. Final fitting will require trying both types of springs to decide which works best in your particular knife. Whichever spring is used, the length of the spring will be trimmed at assembly. These springs are available from MSC in their catalog or on-line.

4-40 button head stainless Torx screws

1-72 and 2-56 stainless Torx screws, both flat head and button head.

Hardenable steel round rod 1/4" diameter for the plunger button. 0-1 or A2 steel


One .250" O.D. x 3/16" I.D. bronze bushing at least .140" long

A small piece of brass shim stock .005" thick to make two pivot washers, or two 1/2" dia. x 3/16" diameter x .005" brass washers

Handle scale material of your choice, linen micarta suggested.



Duration of course: 45 days

Cost including the CAD design: $89.95

[Don Robinson]

Here's an example of the knife we'll build together.