Cycle Repairing and Adjusting
With a Chapter on building a Bicycle from a Set of Parts

66 CYCLE REPAIRING off by placing the work in tanks of hot potash ; but this will, of course, be outside the scope of the amateur under- taking one set of work only. Many scrape the enamel off with a blunt knife, finishing with emery-cloth ; but this is a slow process, and may be improved on if a brazing blow- pipe or blow-lamp is available. Heat about 1 ft. at a time until the enamel is soft, and then scrape off ; or if a wire brazing brush is at hand, brush it off with this. The blowpipe and wire brush is quite a satisfactory method, especially when getting round the lugs and awkward places, where cold scraping would be very tedious. This method is said to be injurious to the tubing ; but it is not so, as the heat used tends to release any stresses which may be present in the steel caused by the vibration and constant use and hammering on the road. The heat should not be sufficient to make the lightest tube at all red, but just sufficient to soften the enamel. The use of a chemical enamel-remover is possible, but not customary. For this, dissolve 1 lb. of common caustic soda in 1 gal. of water, and apply this hot ; allow to stand for a short time, then wash off with hot water and a brush. Take care that the caustic soda does not get on the hands, as it has a powerful action on the skin. Polishing.—When all parts have been thoroughly freed from enamel and cooled down, finish off with emery-cloth, using No. 2 or No. first, and finally polishing off with FF or 0, well scouring the tubes lengthwise and finishing off round the lugs with narrow strips of cloth used cross- wise. Now the finish and appearance of the enamel will depend