The new tool grinder
For years now I have been sharpening my end mills free handed. See the tool section of these pages. Although this procedure served me well I found it time to upgrade to something more professional.
At my work I use a small handsome machine for sharpening chainsaws. For quite some time I had my mind wondering if this machine would be capable of doing something useful for me. Instead of just helping in the demolition of trees.
Having made up my mind I duly bought a similar machine but with more flexibility regarding the angles at which the head could be tilted.
A lot of designing and burning the midnight oil later I came up with a design as can be seen in the picture below.
My main concern was that it should use the same holder / collets as the milling machine. The latter is equipped with a R8 spindle. This to avoid having to buy yet another set of expensive collets. Also it would be a big advantage to be able to take the whole holder from the milling machine to the grinder without the need to remove the cutter. The latter is desirable as I have quite a few mills that spend their lives fixed in their own holder. Also the bigger face/side cutters would stay on their holder saving the need for a special adapter for grinding.
A view on the whole holder.
This looks quite heavy due to the need to take the R8collets. In order to save as much weight as possible I used quite a lot of aluminium during the construction. Rough adjustment of the position of the toolholder is possible by loosening the bolt on the fine feed bar and sliding it forth or back. Fine feed is once the holder has been locked to the bar with the adjusting knob at the rear. The positioning of the mills teeth relative to the stone is done by positioning the R8 holder in the spindle and locking it with the drawbar and handwheel at the rear end.
This is a view on the business end where the action takes place. By tilting the grinding head over I can set the angle of the teeth towards the centre and by swinging the whole tool holder round I can set the angle of the backing of the teeth.
Finally a view of the division end. A simple spring loaded pin is gripping in a 48T wheel which should give me all the needed divisions.
Some experiments have already been done and the result so far is very encouraging. As with all new tools it takes time to get the hang of things. Also some extra safeguards would be not out of place if only to keep the grinding grit at bay.
Remains only one problem to be solved: finding a suitable place to mount it as space is getting a bit tight by now.