SPLIT BAMBOO RODMAKING 179 



is exactly at right angles with center of gauge? 

 the device may also be used for clearing the 

 groove in your block from dust, and in true- 

 ing it up while you are making it as well. I 

 made my gauge considerably wider than Mr. 

 Letterman's, so that it is of convenient form 

 to hold in both hands while it is used as a 

 groove scraper, and its wider bottom makes it 

 more accurate in trueing the grooves. 



The small end of groove is to be ^ inch 

 deep. Therefore, do not plane that end 

 deeper than 5-64 inch, but plalne from the 

 24-inch mark to the large end, then from the 

 12-inch mark to the large end, and so on, gaug- 

 ing frequently. When the groove is approxi- 

 mately 3-64 inch shallower throughout than it 

 must be when finished, lay aside the plane and 

 thereafter use the scraper only. Set it at 7-64 

 and scrape forward and back until that depth 

 at the small end of the groove is attained. 

 Then scrape from the 3O-inch station toward 

 the large end, and so on, gauging often, until 

 the depth at each station is 1-64 inch less than 

 it should be. When satisfied that the groove 

 is true throughout, the final scraping from sta- 

 tion to station, witL a change in the gauge for 

 each, will result in a groove that is only a trifle 

 less accurate than one made on a machine. 



