Wood Field Cameras - Rack & Pinon Designs

I am new to working with 4x5 cameras - been active less than a year and have a question about designs. I have only handled a few cameras and have shot with only a Shen-Hao and Wisner. I bought a Wisner over the Shen mainly for the double extension feature.

I have been using a Wisner Tech Field and have been running the pinon gear off its rack when focusing quite often. I know it is easy to just push it back on the rack but I find this a little irratating and am wondering about other camera designs.

Does anyone make a wood field camera where the this does not happen? Looking at pictures of cameras on the net does not give an indication of how they actually work. I have noticed that Wisner and Zone VI designs have their gears set more towards the center of the base and others like Ebony seem to have them at the ends - does this make a difference? Are they geared for the entire travel distance?

I too have a Wisner Tech Field that I use and the thing that you mentioned is my major complaint with the camera. Mine has actually got triple extension and one has no gear drive at all.

I have owned a 12X20 Korona, three 8X10 Deardorffs, and a 4X5 Zone VI. These all had stops to eliminate the problem you mention...although I must admit that sometimes the Deardorffs and the Zone VI did exceed the travel of the rack.

I haven't found the problem bad enough to work something out on the Wisner...I guess I just got to the point of recognizing and accepting this idiosyncrocy.

If you seriously want to correct this problem on the Wisner, you can drill and tap the rack gear and screw in a brass screw into the rack and this will stop the problem for you. You can tell which end by observing the travel of the extensions.