I have been trying to learn how to turn hollow forms. I have two hollowing systems, both of which I have picked up used and have a variety of parts some of which have been modified. I haven't really had any instruction which has led me to the door step of frustration.
The two hollowing systems area a captured (Jamieson) style and an articulated arm (Monster) style. Both have 3/4" boring bars. I have one round carbide cutter (~5/16 inches in diameter?), and some round and teardrop cutters (high speed steel?), and some 3/16 square cutters (high speed steel or carbide?). I have found the round carbide cutter to be very aggressive and hard to get a small controlled cut without being grabby and causing vibration. I am turning on a Jet 1642 lathe. I have several tool holders for the 3/16 cutters and they are the ones that I am trying to understand and use for removing the majority of the material. I have a straight tool holder, and two curved holders with one being more curved than the other.
I understand that I should have the cutter on or maybe very slightly above center. That leads to another problem, my tool rest that came with the lathe sits higher than I really want, even when bottomed out on the banjo. In both systems, it seems like to get the cutter on center, the hollowing system support is slightly higher than my tool rest. I have sharpened the cutter on my grinding wheel to get a burr.
My biggest misunderstanding seems to be around the orientation of the cutter. I have attached two photos. The end of the tool holder has a bevel that orients the cutter in a downward angle. Then, depending on the angle that I have the cutter directed depending on the slope of the surface I am cutting seems to cause that angle to be variable as well. There is a set screw on the tool holder and also the boring bar so there seems to be a lot of adjust ability. I do not know what is the correct orientation. Rather than cutting chips, I am creating dust and I know that is not correct. I do not believe the cause of the 'dust' is an unsharp tool but rather the presentation of the tool to the surface.
Can someone more experienced provide some advice on adjusting the cutter and tool holder for hollow cutting? My next step is to rough out a bowl and try using the hollowing cutters on a bowl interior just so I can see better what is going on. I'm tiring of the trial and error and looking for some direction. I have watched many videos done by skilled hollow former turners but can't seem to find anyone who discusses this or shows the tool orientation.
Thanks in advance for any help you can provide.
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