Charlie,
They say your brain works the best and is the most creative in the morning..... Especially after a cup or twelve of joe, haha !
I went to the link you posted like I should have two days ago and really started looking at the system for holding the stones. It would be easy for Ron to offer a extra wooden block with a hole drilled lengthwise to hold a ceramic rod or a chainsaw file. Hard to explain here without being able to draw, but drill the hole beginning in the front of the wooden block,( the end that faces away from you as you are sharpening ). Drill back toward the rear end of the block, but do not drill all the way thru, leave a blind hole. This will serve to hold the rods in place as you push the block away from you in the sharpening process. close the open, front end of the hole with a piece of tape, no force needed to simply hold the rod in the hole, all the pressure is towards the rear of the block which has the blind hole for support. You will need to cut away all the wood between the front and rear of the wooden block to expose the, "captured rod " , leaving an " ear " on each end that holds and supports the rod. If the hole is the correct size it will allow a chainsaw file to rotate and use the entire surface of the file. As the file is pushed into the blade it will naturally rotate.
If you are not a woodworker a simpler method would be to buy two spring clips, ( like the ones that hold arrows in a arrow rack ), and screw them to a wooden block. You would need a hard stop on the rear of the wooden block extending past the rod to give the rod something to push against as you push the rod across the blade. A simple piece of wood or metal extended down about 1/2" would work. Just load the file or ceramic rod of your choice into the clips making sure the rear of the file or rod was against the rear stop for support and away you go.
If Ron wanted to offer this on a production basis it would be very simple to have a plastic rod holder moulded which would make it much more cost effective I would think ? If not then I think I will be buying the diamond knife sharpening kit and make me a wooden rod holder myself for now. This should solve the problem of the big ole concave edge on them Treesharks. JMHO
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