Hollow Form Interior Surface Finish?

[Steve Mathews]

I'm somewhat happy with my latest attempt at hollow forming except for the interior finish. I tried to create a smooth finish but I still end up with small ridges and bumps. The thickness is consistent though. I'm using Lyle Jamiesons' setup. Is the interior finish that important?

[roger wiegand]

Only to other turners.

A radius scraper tip, like these that Trent Bosch sells, can give a much smoother inside surface.

[Richard Coers]

The general public doesn't even look in the top hole, they are just baffled how you made it that light weight. Only woodturners look and feel inside the vessel. You can get a better finish if you lighten up your grip and concentrate on smoothing and not cutting.

[Brice Rogers]

I attended a demo by Mike Jackofsky who has done several thousand hollow forms. Based on that I bought a really big locking hemostat (Harbor Freight) and wrapped coarse sand paper around a piece of fairly stiff foam (Harbor freight foam mat) and locked the hemostat around that small wad. It works great. But I agree that only wood turners will stick their fingers in there. So don't bother going too deep

[alan weinberg]

I attended a demo by Mike Jackofsky who has done several thousand hollow forms. Based on that I bought a really big locking hemostat (Harbor Freight) and wrapped coarse sand paper around a piece of fairly stiff foam (Harbor freight foam mat) and locked the hemostat around that small wad. It works great. But I agree that only wood turners will stick their fingers in there. So don't bother going too deep

just keep your fingers out of the hemostat in case it grabs.

[Brice Rogers]

Alan, your advice is probably good. One can never be too safe.

But when I wrap the sandpaper around the (roughly) 3/8" dia. piece of foam and insert it, it immediately folds over in a controlled and predictable manner and sand the inside without any excitement, exactly like sanding the outside of a piece. I have never had even the slightest hint that it could catch. I suppose that if the inside was really really rough and had big chunks and slivers facing forward or if I forcefully jammed the hemostat in that it could catch. I think that the biggest risk might be if a person jammed the hemostat into a very small opening that the hemostat could get stuck in the opening. I think that is the real risk. But I may be working with a 2" opening and a hemostat width of maybe 3/4 inch or less.

When I'm sanding the interior I might start with 60 or 80 grit and stop around 150 or 220. It is a fast process. Also, I don't spend very much time sanding deeper than a person's finger can go.

[Neil Strong]

Also, I don't spend very much time sanding deeper than a person's finger can go.

===> Ditto!

[Steve Nix]

AZ Carbide teardrop scrapper are the best I’ve used on an articulating hollowing device.

[Peter Blair]

Here are a few photos of what I made up to sand inside hollow forms as long as the opening is larger than 1 1/2". I often also use them on vase shapes. It has a handle that is about 16" long.The rounded end does a nice job of the bottom.
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