Turning the End of a Rod

Suggestions for tackling the problem of turning a 1.5-inch diameter rod down to one inch — but only at the ends.October 17, 2012

Question
We have a 60" plus long rod that we have to process 1 1/2" long on both ends down to 1" diameter. Currently using a fixture on a table saw to rotate the rod into and over the saw blade to remove the approximately 1/4" all around to get the final 1" diameter dimension. This method is not giving us the dimensional stability and finish that we need on the now 1" diameter part of the rod. We also cannot have a fillet in at the meeting of the 1" neck down to the 1 1/2" diameter of the rod due to what we attach to both of the rod ends.

We are looking at some sort of holding fixture for the rod that does not use the tablesaw as the cutting method. I’m open to a lathe, router, or other cutting methods. This is a low volume process so we do not want to invest money into the capital purchase of a dedicated machine. We want to create a fixture attached to a stock off-the shelf (and possibly able to be purchased used) machine.

Forum Responses
(Solid Wood Machining Forum)
From contributor D:
A straight bit in a table mounted router would work. It seems like the tablesaw blade leaving a fillet must be due to grind of the teeth or your track for the rod is not perfectly perpendicular to the blade. A router in a table can be kept out of the way though. Tying up your tablesaw just for this task would impede other work I'd think.



From contributor R:
The router would be my choice, but I would build a simple jig to control the dimensional accuracy and feed the end of the rod into a 1.5" hole where it meets a straight cutter set to 1/4" depth of cut. A stop on the far side of the bit keeps the length correct.


From contributor E:
Have you considered going back to your supplier and asking if he can supply the rods with the ends already cut in? This does not sound like a stock part and may be lower cost in the long run.



From contributor U:
I used to produce a product like this. The problem with registering your cut from the edge of your dowel is that any variation on the OD will transfer to your 1" tenon. What I did was to have a plug cutter modified to cut a clean, square shoulder, and chuck it into a horizontal boring machine. Nordic Saw did the custom grind on their cutter, if I remember correctly. The rods were held with a DeStaco clamp jig. Centering may be off still if dowel OD is not exact, but you can design a way around that in the holding fixture if you go this route.


From the original questioner:
I had forgotten the tenon cutter idea or term. Unfortunately, our supplier is unable to process the end features on the rods both due technical items and too much cost increase to add the end processing.

What we are facing is that we want a person who is not trained in lathe operation or wood turning to be able to make the detail on the ends of the 60" plus rod (similar to a closet rod) before that person attaches components to the processed ends.

We are trending toward a dedicated router fixture and operation now since the final diameter of the end would just depend on the spacing of the router bit to the (theoretical) center line of the rod. This makes the rod positioning and holding so that the person can spin it against the router bit - one of the critical issues for dimensions. The set up cutting length of the router bit will determine the length of the cut on the rod as now the idea is to have the rod bottom out against the router base - given 90° of the end face of the rod to its length.



From contributor B:
How about a horizontal router table (5' off the floor)? The one 12" rod is stuck up through a hole in an attached block of wood beneath the table. The router in its base is run around the end of the vertical rod and within a circular ring form which is attached to the top of the table. Of course everything must be concentric and the off-set between the router bits' cutting edge and its base and form must be precise. This should cut perfect dowels every time. A worn bit is discarded rather than sharpened.


From contributor S:
I do precision work with dowels and size variation is important. Dowel rod has a huge variation in it that makes edge-positioning useless. I ended up using a self-centering clamp and then worked the piece on a vertical mill. The machine it's worked on is probably not a factor so maybe such a clamp would solve your table saw setup.

Another suggestion is to center bore the end of the dowel and glue in the pin. Doing this required me to get a set of custom sized boring bits to accommodate all the dowel size variations. Four sizes of bits did the job for me. I sorted the dowel with dial calipers into four size groups. Center boring is standard stuff for a drill press, vertical mill, lathe, etc.