Beginner's guide to tailstock alignment

If you want to turn parallel or drill small holes in the lathe without breaking bits, lining up the tailstock is essential. Pete Barker shows how simple it is.

Setting your lathe’s tailstock alignment, photo 1, is something any beginner can do by following a few simple procedures. The first step is to determine how far out of line the tailstock is sitting. The second is to adjust the tailstock using the simple mechanism provided on most lathes. The third is to test the result by turning a bar between centres and measuring the diameter along its length, aiming at the same reading at both ends -- and in the middle of course.

Providing your lathe is in good useable condition, needing minor adjustment and not major surgery, the following steps will soon have you turning parallel. It will also help prevent bit breakages if you have to drill small holes.

The quick way

The easiest way to see what is going on between your lathe’s centres, the headstock centre and tailstock centre, is to place a thin steel ruler between the points and gently turn the tailstock handwheel until the ruler is firmly gripped, then tighten the barrel lock. The tailstock base clamping lever should be locked before advancing the barrel. If the two points are in line, the ruler will stand up straight vertically, photo 2, and lie square across the lathe bed horizontally. This can be judged very closely by eye. If the ruler sits at an angle in either plane, photo 3, the tailstock needs adjusting as described in the second half of this article.

If you don’t have a second dead centre to put in the headstock, you can use my preferred method of gripping a short length of 1/2” (13mm) bar in the threejaw chuck and turning a point on it by offsetting the top slide to 30 degrees, photo 4. The angle is not critical, nor is the concentricity of the piece of bar in the chuck. With the tool bit set at centre height, the turned point will be bang-on true to the spindle axis.