[BIGBLOCK1965]

I found a good deal on E-Bay for a 5C collet chuck, but it requires an adapter plate to fit my spindle. I had a piece of 1/2"steel drop from some old project that was just the right size and it had a flame cut hole in the center almost the perfect diameter. I chucked it up with my outside jaws first and bored the center hole true and to size to fit over my spindle. Then I took it out, changed to the inside jaws and gripped on the center hole and faced one side. I then turned it over and faced the opposite side, turned the OD and turned the shoulder diameter to fit the collet chuck recess. I clamped it to the mill table on top of a piece of 3/4 MDO and did the drilling by hand. I first found center with a center finder, then using the bolt hole function in my DRO I moved the table around by hand to drill the 3 different hole patterns. The center 4 holes with the counter bores secure the plate to the spindle. The next 4 hole pattern fits a 4 jaw chuck that I had and I used a bushing to center it to the spindle bore. The outer 3 hole pattern and the shoulder fit the Collet chuck.

[instructor37]

Those collet chucks are a bit quicker to use than a drawbar style, but are limited in accuracy to how well you make your adapter and the spindle itself. I found an inexpensive way to get accuracy to any level you want. I use a square 5C collet block held in my 4 jaw chuck, and I can dial in the collet to whatever degree of accuracy I want. All I needed to do was make a drawbar to fit through the spindle to tighten the collets. A happy coincidence is that for really quick work I can use the Hex collet block in the 3 jaw chuck. You can buy those 5C collet block sets on E-Bay for about 40.00 and they have a lot of other uses as well.