Scroll chuck set screw for reversing

[Tom Wilson66]

Have finally found a way to get my Jet 1014VS to run in reverse. Problem is my scroll chucks don't have the set screw to keep them from spinning off when running in reverse! I believe the answer is to drill and tap the chuck for the screw, and use brass tipped set screws, to keep form messing up the spindle threads. My question is: do I need anything special to drill the chuck? Is the metal in the chuck or the insert hardened, and require more than a HSS drill bit? How do you hold it to drill the hole on a drill press? Or can it be done just putting the chuck in the bench vise and drilling with portable drill? Any info would be helpful. My chucks are my friends and I want to treat them right:D

[Jim Sebring]

I have several Nova chucks that have grub screws in the inserts. I haven't needed to drill and tap those, but have drilled and tapped some of Don Pencils aluminum faceplates for grub screws. I used 6mm set screws to remain consistent with my chuck's screws. Although brass or nylon-tipped set screws are available from McMaster-Carr or Enco, I just used common, locally-available, steel screws. I do use a #2 lead shot pellet between the set screw and the spindle to prevent marring the spindle shaft. I took apart a shotshell to get a supply of pellets. Each pellet is good for one use.

[James Combs]

I drilled mine for a set screw but it was the insert that I drilled. The chuck is a SN2 and came with an adapter insert to fit my 1"8tpi spindles. The chuck already has a set screw to retain the adapter insert in the chuck. Before I put the adapter into the chuck I clamped it on my drill press and drilled a hole in one of the hex flats taped it for 6mm and installed a set screw. My chucks BTW came with two small pieces of leather that you put into the set screw hole first before the set screw. I used one of them for the new set screw that I installed in the insert. I would think that any small piece of leather would work and I have never had to change it as is done in the previous post using the #2 shot.

Hope this is helpful. BTW most chucks do require an insert, the only one I am aware of that doesn't is the Delta branded Nova G3 chuck but I don't have a lot of experience with other chucks or with any chucks that are differently threaded then for 1"8tpi so take this statement with a grain of salt.

[Tom Wilson66]

Thanks for the replies. Already have some 1/4" brass tipped set screws, so I'll just use those instead of the 6mm. Just thought might be some way of avoiding drilling and tapping them, but doesn't look like it.

[Jim Burr]

I think it was Mr Keeton who mentioned lead shot or a sinker between the set screw and the spindle. Seems nice and soft so as not to mar the threads...cheap too!