Archive: Apr 2015

How to Install Cuphead Weld Pins

Install Cuphead Weld Pins


At Midwest Fasteners, we know that getting work done quickly and reliably is really important these days, and we have a way to help with that. Easy to use, easy-to-install Cuphead Weld Pins.

It’s a fast and practical way to get jobs done less expensively, quickly and reliably.

Cuphead Weld Pins, sometimes called “Mini” Cups, can be applied using Capacitor Discharge stud welding, a process often called “CD” welding for short.

The Cuphead pin is used to erect-and-install insulating materials all in one pass saving money by doing the fastening work quickly, and with a reliable welded fastener.

Cuphead C.D. welding is a portable process which uses readily-available electric power from an everyday, one-hundred-and-ten-volt power outlet.

In addition to being portable, CD Welding Systems have:

  • simple components
  • they work quickly
  • and can be used on sheet metal thickness material to apply Cuphead Weld Pins and a variety of Welded Fasteners using the capacitor discharge method.

The process of Capacitor Discharge welding occurs in a series of 4 instant steps:

  • Contact
  • Ignition
  • Placement of the Stud or Pin
  • and, “Completion” of the Pin Weld

We’ll use a standard MIDWEST Portable C.D. system to install the Cuphead.

Here’s how to set up for proper installation of Cuphead Weld Pins.

Using the standard, portable CD system, we see it consists of:

  • a Controller [or Power Unit] which is plugged into one-hundred-and-ten-volt power.
  • the CD Gun with Cables which is used to control the power unit, to deliver weld current as it serves as the Pin holder, and also to place the pin properly during welding.
  • a ground cable and clamping connection which is attached to the work to provide the rest of “the circuit” to our weld system.

And finally, special Accessories to fit the “Pin” to the Gun. These parts make up the CD system and we are ready to install the Cuphead weld pin.

The Gun is prepared with a Magnetic Chuck as the accessory which is needed for this type fastener.

Cuphead pins, properly sized and of the proper type for the material, are held in contact with the gun prior to welding by the Magnetic chuck–either on the gun or pre-placed in the material.

In this case with insulation material in place, the gun-mounted pin first pierces the material, making contact with the metal surface to be insulated. Light pressure is applied to the gun by the installer, the trigger is pulled, and the CD process completes the weld just that quickly.

The equipment now recovers, instantly, as you break contact with the welded pin, and is ready for the next weld.

The Cuphead weld shows NO backside burn-through with the weld providing good strength from the bond.

The Strength of the cuphead weld is to provide support of material installed and to prevent pull-away of material once welded. To properly strength test a cuphead weld, pull away by exerting pressure from the underside of the welded fastener-head.

Since the CD process can deliver 15-20 welds per minute, material is installed quickly and cleanly.

C.D. Cuphead one-hundred-and-ten volt systems can weld as quickly as you:

  • Load
  • Contact
  • and Apply

When applying through FSK or “foil-faced” material, always use an “insulated” Cuphead…one with a paper-covering on the underside of the washer-head. This prevents arcing and burning of the foil face during welding.

Apply light pressure, about one-eighth of an inch of down-force, on the gun & gun spring during the entire welding cycle. This allows the burn-off process of the Cuphead CD weld to occur properly and creates the strongest weld bond possible.

Cuphead pin length should allow for this burn-off, and many users DO prefer a Pin about one-eighth inch longer than the material to be installed.

Finally, be sure to pull the gun away “after” the weld cycle is complete—many operators like to wait for just a second longer after the trigger pull to assure that the welding is complete before moving the gun.

Best results come if you do NOT pull-away during the weld, making sure the cycle is complete before re-loading.

The finished Cuphead weld shows the advantages of Capacitor Discharge welding; with NO backside distortion or burn-through. The weld provides good strength from the bond, and fastening is created in a short cycle which exhibits strength sufficient to support materials without falling down or pulling loose.

Midwest Fasteners’ Capacitor Discharge stud welding is fast, reliable, and gives superior weld strength on Cuphead weld pins and many types of fasteners.

For more information on Cuphead and CD Stud Welding, please visit our industry-leading website at