I wondered why Sears doesn't make the 6" extension with a handle in anything but the 1/4" drive. They don't, so I did. I made my first two a year ago, but didn't want to post them because they look like rubbish. They were just experiments and they were for me, so appearance was secondary to function.
These are two that I just finished today as Christmas gifts. As gifts, appearance was more important than it was for mine, so I took way more time on the finish.
I made them from Craftsman bottle openers and 6" Craftsman socket extensions. I started with the bottle opener because it is easier to pull the shank out (heat it a bit and it slips out) than does a screwdriver. I built a jig to hold the handles vertical in my drill press, then carefully drilled it through until it was a tight interference fit.
The jig was made out scrap wood. I have photos & video if anyone wants to see them, though anything that holds it vertical without spinning or scarring it will work.
Next step was to chuck the socket extension with the handle into the drill press and cut the palm knob off with a coping saw.
Next I used part of a golf club shaft and cordless drill to shape the cut end with a belt grinder, which was followed up by a round of hand sanding and shaping up to 800 grit. I also sanded the bore a little to knock down any errant gouges. No need to get it smooth. More on that later.
The last step of the shaping handle was to flow the re contoured end with a heat gun, alternating with dips in cold water to counter sag until it had the factory gloss. A quick denim buffing and they were ready.
The final step is to completely coat the bore with 2-part epoxy and shove the extension through. This squeezes out the excess epoxy and forces it into all of the scratches in the bore. I used crystal clear epoxy for the first two that I made, but went with standard yellowish epoxy this time. Wiping the excess away leaves a nice radius of epoxy between the handle and extension, further hiding any evidence of tampering.
The handle end is bored out a little wider to let the extension sit into the end. I think that it looks better, and makes a nice pocket for epoxy.
Adding texture to the extensions would strengthen the bond, but it holds well enough to spin bolts/nuts in, which is their purpose. It's mostly to enhance the friction fit.
It would have been a lot easier & cheaper to make handles from scratch or use opaque handles, but I wanted them to look like factory-made Craftsman items. The polysomethinorother material of these handles is amazing to work with, but very unforgiving. This is a thermoplastic with a narrow working range between solid and blob. I learned that the hard way on my first few attempts. See also the melted end of the unfinished 3rd one.