I will be taking delivery of a Hammer A31 31 jointer/planer in a few weeks (can finally trash my old Craftsman 6").

I have 2 questions for all the experienced people on SC.

The dust extractor on the Hammer is 120mm outside dimension. My DC system in from Oneida, and all the hoses and pipes are in inches (4, 5 and 6). I currently have a 4" hose (flex) going to the jointer. I could change it to 5" if needed.

1. Should I use a 5" or a 4" hose going to the J/P? I only run one machine at a time, and the total run from the cyclone is about 6 feet of metal duct (from Oneida) and about 6 feet of flex hose (also from Oneida).

2. Can you recommend an adapter or other solution to connect the 120mm outside diameter dust exctractor on the A3-31 to the 4" or 5" hose. I suspect that Oneida makes can make some type of fitting (cost is not an issue), but is it best to have an adapter right at the machine, and attach it direct to the flex hose. Is a quick release coupling of some type preferred? Any other solutions.

I am sure I am not the first person to deal with this question. I recall seeing some posts from Jim Becker on a similar hook up from a few years ago, where he talked about using a Fernco coupler.

Any input would be most appreciated.

Thanks in advance.

Steven