For many years I have used a ruler on my radial arm saw (RAS) fence, and instead of measuring for crosscuts, I just place a stop block at the proper point on the ruler. This is a second generation solution, to remedy minor issues with effective fence height with my first one. I find that my placement of block is accurate to less than 1/64 of an inch, a few thousands of an inch measured with a digital caliper, in routine use.
First I will show you the fence in place on my saw, because then everything else I say will be more understandable.
View 1 – The fence, and the stop block with a Vise-grip clamp (simple, inexpensive, works great)
View 2 – The stop block up close. To position it, you sight along the acrylic piece that is colored with a Sharpie on the edge, creating a very fine line. Because the stop is exactly 10” long, to set it for 0.5 inch, you can read 10.5” on the back side which is easier.
View 3 – The label that has been placed after the fence position has been tested for accuracy. See below. Note the vise grip clap that is used to clamp the stop block sitting on the shelf.
There are three considerations:
1. Indicator for fence position so that you know the fence position is right for the current blade, and has not moved.
2. Placement of the ruler and cursor so that it does not decrease effective fence height and is readable.
3. Setting of the block for short distances where visualizing the ruler is compromised by the saw motor and such.
1.An adhesive label with vertical lines, that is thin enough to not influence the position of the workpiece. If the fence is out of alignment, it is obvious at a glance. I always give a quick look before cutting a piece.
First verify the the fence is properly placed. I adjust the fence and then cut a piece of scrap placed against the stop block and measure it with a caliper. I use a digital one made by Wixey. Then adjust and cut until it is perfect.
Then place the label against the fence so that half of the label will be on the table. Knock it into position with a block of wood. Then cut it with a box cutter or other, right at the junction between the fence and the table. Mark it, if you wish, with the blade model in use. You can use other labels for different blades.
2. I used a ruler that was placed in an indent on the face of the fence originally. This reduced its effective height. This time I placed it on top of the fence, and used a piece of acrylic for the cursor. Much better.
3. Make your stop block exactly 10 inches long. Then you can sight off the back of the block, i.e. 10.5 inches = 0.5 inches on the front of the block.
I made the label myself with a Brother label maker. But, any label with lines you can orient vertically will do. Even a piece of lined paper glued in place.
This is one of the best time saving things I have done in the shop. It also improve my measurement accuracy.
It may be applicable to any tool that uses a movable fence.
If anyone is interested and has questions about how to cut the block and acrylic, etc., let me know.
-- Jim, Anchorage Alaska