3/8" Pop Pins - for the backyard exercise equipment builder, or large manufacturer - we have you covered with more than 20,000 pieces in stock for immediate shipment. These are designed to weld-on to your adjustment application. They are perfect for non-fitness applications too!
Engagement pin is .375" O.D. The length may vary somewhat, but at a minimum is .375" long. The pop pin main body OD is 1" and the length is approx. 1.575" (length may vary slightly from batch-to-batch). The cap screw has a black phosphate finish. It will not rust or wear off. The thread on the cap screw is 3/4-16. Unlike other models, this fine thread allows the cap screw to be tightened with less effort as compared to the coarse thread variety - which tends to loosen.
The inner spring-loaded pin is zinc plated for corrosion resistance and includes an extension spring for medium spring-loading of the pin.
The main pop pin body is welded to the outside of an adjustment tube (or whatever is mounting it). The cap screw can be left off during powder coating, painting, and bead blasting. And reinstalled later after the finish is applied using a pair of pliers. The cap screw has a serrated outer periphery to aid in griping with pliers.
Some other models do not have this deeply serrated surface and rely on a knurled (or even smooth) surface to "grip" the pliers during installation - thereby making it unable to adequately tighten the cap screw so that it won't loosen in the future. It is a hassle to continuously re-tighten (by hand) the cap screws on exercise equipment.
One big difference between our model and others out on the market today, is the close tolerances in the clearances maintained between the inner pin and I.D. of the pop pin body. They are approximately .012" to .015" clearance. This makes for a "tighter" feel to the adjustment.
The surface of the I.D. of the pop pin body is very smooth as it is on the inner pin flange - which contacts the main body I.D. Making adjustments feels friction-free and effortless.
The ball knobs are made of black phenolic with 3/8-16 internal thread bulkhead. Other types of knobs may be used at your discretion.
By far, these pop pins are the best we've found anywhere after more than 25 years of exercise equipment manufacturing experience!