I want to hollow out a pine log about 5-6 inchs wide. I tried a 3 inch forstner bit and it just will not do the job effectively. I only want to go down about 5 to 6 inches as well. Any suggestions?

If you don't get a response, send me a PM. I know someone on this site, who may be able to help. Sounds like a lathe issue and it sounds like a power issue. The larger the diameter of the hole the more power required. A lathe can take small amounts of material at a time. I have a nut bowl which is about 2" deep which is made that way.

5" deep might be difficult, although I'm more familiar with metal machining. A boring bar would generally be used, once a smaller (1-2") hole is drilled.

I take it that you are trying to drill out the end grain. Are you using a hand drill or a drill press? What exactly is the problem you are having? Is it the slow cutting or the limited depth?

Forstner bits are nice in that they give good control and make a nice hole. They also require quite a bid of pressure because of the amount of material being removed. Therefore work best in a drill press. Extensions are available to increase the depth of cut.

Tell us a little more about what you are trying to do.

I want to make a coffee mug for show only. So to do it I need the center drilled out smooth. The firstner bit seems to want to burn through more than cut and is extremely slow. The bit is new and sharp

Bob

Drill a series of holes around the inside perimeter, leaving the center with a spade bit, then drill with the forsner bit cleaning up the sides and the bottom.

Be aware that the bottom will most likely split unless dried very, very slowly, 6 months wrapped in several paper bags. Also if you are trying to keep the bark it will most likely come off after it dries.

Thank you very much

Bob

Figured Harold would see this.

The hollowed out log will stand time much better if varnished or stained with shellac.

Have a nut bowl and the bark is still in good shape after 20+ years or so.