Tell us what you're using them for
They are being used to attach a steel liftgate system to an aluminum trailer.
Have you enough material thickness to prevent pull through after countersinking? What electrolysis prevention measures are you taking?
Yes there is plenty of thickness, and the holes through the tube are slugged so it can't collapse. The aluminum is a custom double hollow with 0.3125" wall, the steel flange is 1/4" plate.
We will use the same electrolysis prevention as is used to attach steel axle subframes to aluminum trailers, or steel tongue, gooseneck, kingpin, and A frame couplers.
This isn't something being built in my backyard.
I was hoping there was a diverse enough occupational background among the members to help source a piece of hardware that I had not ever tried to locate before.
