EXCLUSIVE FORUM FOR MACHINE DISMANTLERS AND REPAIR PEOPLE > Dolton IL
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> High Frequency Converters
> Under 1 MhZ
> Lot 100 rubber powder coating painting thread hole plug
Lot 100 rubber powder coating painting thread hole plug
This item was acquired at a salvage freight sale recently. Based on nearly five minutes of exhaustive research, I have concluded that these are probably little plugs used to protect threaded holes in metal during painting, powder coating, and possibly plating operations. Otherwise, your paint or coating material will gum up all the threads and your screws won't go in. Just insert the end adjoining the thin ring and pull the ring completely through the hole. The ring then draws back and seals against the surface, while the thick portion seals the other side of the hole. Also works great for plugging holes in restroom stalls if you're forced to work around a bunch of congressmen.
They are made from some kind of very stretchy, tough, silicone-like elastomer. They may be suitable for metal plating, but you should test to ensure they will withstand the temperatures and chemicals used in the metal bath. The manufacturer is unknown, and I never could find any additional information online, but they ought to be good for something.
"What diameter and length holes will they fit?" you might ask. Well, they fit a 5/16" hexnut pretty nicely (pictures below), and you could probably seal a 5/16" hole twice that length/depth. As for smaller diameters, the thin ring is extremely pliable. It will pull through even a 1/4" diameter hole if you first snip the little tab off the pulling end.
Diameter (of tabs at very end): .258"
Diameter (at thinnest point): .175"
Diameter (of thin pull-thru ring): .435"
Diameter (of plug flange): .435"
Diameter (of plug step-down): .340"
(11 to 13) lots: Five pounds
