Need Help With Tool Rest Height/Threaded Holes in Banjo

[Steve H Graham]

I have not turned a thing yet. I'm still working on my tool rest banjo.

I need to bore holes for the threaded lever that holds the tool rest stem in the banjo. I notice some banjos have threaded holes near the top. Others are lower down. I guess what I need to know is this: will I ever need to have the tool rest very far above or below the lathe axis? If I have a range for that, I can figure out where to put the holes for the lever.

From a mechanical standpoint, I think the lever screw should be around 1-1 1/4" below the top of the banjo, but I don't want to commit until I have more info.

I can't figure out whether the hole should face me or the tailstock, so I guess I'll make two holes and see which one works.

[Brice Rogers]

You can put the threaded hole either high or low, I don't think that it matters a lot. On my Grizzly g0766, I believe that I have three threaded holes. The purpose of having so many holes is to be able to move to the one that is the most convenient and which doesn't interfere with the locking handle.

Another nice thing about having multiple holes is that if your tool rest is a bit undersized in diameter, a second bolt will 100% snug it up. My primary posts are 1.00 inches in diameter and the modified bore of the banjo is slightly over 1.00 but the tool rest that came with my lathe is 25 mm (.984"). So the OEM tool post is a little wobbly unless I add another bolt or slide in a very thin shim (soda can aluminum).

[Steve H Graham]

Thanks. Very helpful.

[Brice Rogers]

Steve, I forgot to mention the height adjustment.

I have some carbide scrapers that are mounted on top of a 1/2" bar. I generally apply the scrapers flat and on center. So at a minimum I need to be able to lower the rest 1/2 inch below center. For shear cuts using a traditional skew on a spindle, I like to position the rest above center by as much as 1". But that is just one pair of data points. I'm hoping that others will opine.

[Brian Kent]

I think the range I have used is about an inch below centerline for a scraper on the outside of a bowl, to about 3/4" above centerline maximum for the inside.

[Michael Mills]

If building one I think I would go with Brice's suggestion of three holes. Maybe more than the position of the hole is the length of the post.
I have a Nova (long post) and was able to pickup a Delta rest that I liked cheaply. The Delta post is not long enough to raise the rest much above the center point.
Where the holes are located may depend a lot on where the post connects to the banjo and the thickness of the banjo. On my Nova the post is located to the headstock side of the banjo and the lever is on the end. If located towards the tailstock it may interfere with the lever for the banjo itself or be restricted in movement by the thickness of the banjo.

[Steve H Graham]

I won't know what to do until the rest gets here, so I'm waiting for UPS.