How Accurate Should A Table Saw Cut
First of all I will be the first to admit that I am a nit-picker and have been accused of b such all of my life, so with this in mind, let me tell you what is on my mind. working with metal, accuracy to .0001" is often needed and can be achieved with the right tools and the skill of an good machinist, or so I understand, I am not a machinist but in years past I was pretty heavily involved in precision benchrest shooting and did work with tools and measurements that required being able to decern .0001" in swaging bullets and turning the necks on cartridge cases.
When I first got interested in wood working three years ago I was intrigued with Incta's fence positioning system and added it to my new table saw. The system is supposed to advance the fence in .001" incrementss using the micro adjust feature and for the most part it does, but wood is of course not as stable as is metal. I can make several cuts with the table saw with the fence locked down and the cuts will vary in length by three or four thousands of an inch one way or another from cut to cut, which is very good in almost all situations that I can imaginge for woodworking. Or so I suspect.
Using a dial caliper the variation can be decerned when reading thousandths of an inch but when the calipers are set to read in fractions, the error in the cuts is not decernable and this is with calipers that read to 1/128th of an inch which is just a quarter of 1/32". That's pretty close and closer than I have ever needed so far in the work that I have done.
I doubt that most folks reading this care much about such trivels, but they are interesting to me. The feature that I like with the system is that I can set the fence to any position that I want and and on the first cut, be right on the money. This is true if I am careful to keep the scale calibrated and I must admit that the rub comes in here. If the cut is really important, I mean really impoetant, then of course it is a good idea to make a witness cut and to check it like any one would do with any set up, so the value of the system is really up to what the individual expects and/or wants in his table saw. Like I said earlier, I am a nit-picker and like good tools, so the Incra LS Fence Positioning System turns my crank as they say. Like any tool, it is only as good as the operator.
The accuracy of the system really comes into play when cutting dovetails with the system and since I have never tried to cut dovetails with any other system, I don't know any better. It took a lot of practice to learn to cut dovetails so that I was happy with them, but practice paid off for me and the system work for me to my nit-picking satisfaction.
If anybody out there has the Incra set up and would like to compare notes, I would like visit with them about it, or if you just have questions about the system, let's talk.
Just wondering how others feel about such things.
Colorado City, TX