Thanks for your reply it will be used mainly for degree in camshaft I did have a look on eBay all I could find was 2 to 2 1/4 inch clock face ones I would like something larger easier to readprice depends on the resolution you require
but seeing as i work with these things all the time i would say if you want to do anything accurate to less than 25micron spend more than £50 so it depends what your going to use it for
many that appear on ebay have failed calibration and cant be used in industry that depends on traceability of all its products and test equipment.
good makes are:
mitutoyo, marposs, diatest, hahn & kolb, ATORN, Etalon and kafer/kaefer to name a few.
up to you but im seeing more and more digital gauges and they generally seem more accurate than the mechanical counterparts especially after they get dropped.
if its for light work of not measurement critical importance a cheapy one off ebay may probably suit your needs.