PS-25CD Stud Welding System
Made in the USA

PS-25 | CD Stud Welding System

The PS-25 is a solid state capacitor discharge (CD) stud welding system designed for welding various standard or metric threaded studs from #4-40 (M3) to 1/4"-20 (M6) thread. It consists of the power pack, weld gun and ground cable. The PS-25 is capable of making up to 20 welds per minute on steel and stainless steel. A 205 piece accessory kit includes 50 each of four different steel CD studs, four different collet chucks and a hex key.


Included Accessories KitBack to top

PS-25 accessories kit
  • Low-Carbon, Copper Flashed Steel Stud

    200 Steel CD Studs

  • Steel banded CD Chuck

    4 Different CD Collet Chucks

  • Included Steel CD Studs:

    • #6-32 X 1/2" (50 pc.)
    • #8-32 X 3/4" (50 pc.)
    • #10-32 X 3/4" (50 pc.)
    • 1/4"-20 X 1" (50 pc.)
  • Included Collet Chucks:

    • #6
    • #8
    • #10
    • 1/4"

Also includes a 2 mm hex key for changing collet chucks.

CD Stud Welding BasicsBack to top

  • CD stud welding baisics step 1 - contact

    1. The stud makes contact with the work piece. This method of welding will not damage paint on the other side of the weld and leaves little warping.

  • CD stud welding baisics step 2 - discharged energy

    2. Stored energy is instantaneously discharged from the capacitors through the stud tip and the stud starts downward.

  • CD stud welding baisics step 3 - fusion of metals

    3. The stud tip and parent materials both become molten and fuse together instantly making for an extremely strong bond.

  • CD stud welding baisics step 4 - cooling

    4. A weld that is stronger than the bolt itself is produced as the metal cools. This can be repeated several times in procession with little cool down required.

Advantages Over Other Fastening Methods Back to top

Steel plate with 2 studs welded to it, showing CD stud fastening.

The PS-25 CD Stud Welder Provides a higher quality fastening solution with less work.

CD Stud welders such as the PS-25 give the user quality, precision, and strength all in an instantaneous jolt. Stud fastening is quick and convenient, and requires less preparation of material than other methods of fastening. In addition to the ease of use and speed, the PS-25 can be used on much thinner materials than techniques like threading which opens up several possibilities for manufacturing and design.

Non-Stud Welding Methods of Fastening

  • Alternative fastening techniques - through bolting

    Through Bolting

    While through bolting is the strongest of the alternatives to Stud Welding, it is not a water tight solution which can result in rust stains. For a flat surface a much thicker parent material is required to counter-sink the nut.

  • Alternative fastening techniques - back welding

    Back Welding

    Back welding requires more steps than necessary to achieve a similar effect to CD Stud Welding. In addition to the longer process, drilling through the parent material weakens its structural integrity.

  • Alternative fastening techniques - inserts


    Inserts tend to crack paint and leave rust stains over time. While they can be used to fasten thinner materials the insert must be counter-sunk if a flat surface is required which can weaken the parent materials.

  • Alternative fastening techniques - drilling / tapping


    The process of drilling and tapping material is much more time consuming than the alternatives, and requires much thicker parent materials and longer studs than any other fastening technique.

Stud Weld Durability Back to top

Pull-tester while testing a stud weld made by the PS-25
  • Stud installed in pull-tester
  • Stud broken by pull-tester
  • PSI reading on pull-tester from destructive test of weld made by the PS-25
Stud weld tensile strength test video

To test the tensile strength of a stud, it is welded to a steel block using the PS-25 stud welder and then inserted into a pull tester. The test results demonstrate that the weld of the studs are significantly stronger than the stud itself. In this demonstration the 1/4"-20 steel stud brakes at 3000 lb. The maximum recommended load of the stud is rated at 1750 lb.

Standard CD Stud Fastener Load Strengths

Stud Material Stud Size Maximum Fastening Torque Ultimate Tensile Load Maximum Shear Load
Low-Carbon, Copper Flashed Steel #6-32 6 in·lb 500 lb. 375 lb.
#8-32 12 in·lb 765 lb. 575 lb.
#10-32 14 in·lb 960 lb. 720 lb.
1/4"-20 43 in·lb 1750 lb. 1300 lb.

Technical Specifications

Construction: 16 ga. (1.52mm) Fabricated Steel
  • 14" x 7 1/2" x 9 1/2"
  • 355mm x 190mm x 266mm
Capacitance: 66,000 MFD
Input Voltage:
  • 120/240 VAC, 50-60 Hz (Autoselect)
  • 15 Amps
Weld Voltage: 50-200DC
Weldable Stud Diameter: Maximum 1/4 - 20 (M6) Threaded Studs
Stud Material:
  • Copper Plated Steel
  • Stainless Steel
Weld Rate: Up to 20 per min.(Based on stud diam.)
Shipping Weight: 42 lbs. (19.05 Kg.)


  • Comes with 200 assorted CD copper plated steel studs
  • Also comes with 4 different CD chucks
  • Welds Up to 1/4" diameter studs
  • 115 / 230 automatic voltage select
  • Solid state circuitry
  • Built in circuit breakers
  • Weld ready light
  • Lightweight power pack
  • Lightweight gun