April 10. 19T2 



HARDWOOD RECORD 



■was overruli'd. The lights went in and I tried my level best to make 

 a successful job of it by making all conduit piping strictly moisture 

 proof at all joints and outlets, using the very best of Okonite wire 

 and marine type glass covers over the lamps, secured to the outlet 

 box with rubber gaskets. Positively no chance for water to get in 

 from the outside of this conduit system. 



Yet six months from the completion of this star job not one of 

 these lamps was burning, or could be made to burn, because the 

 wiring itself went to pieces; 



This was just what I was afraid of, because frequently they 

 turned live steam into these kilns for twenty minutes to half 

 an hour. 



The operator and the superintendent don 't exactly say so, but 

 they let me feel as if my work was to blame, so seeing your paper 

 on the yard office desk I have made up my mind to collect some 

 war material by asking your readers if any of same are able to 

 maintain such lighting equipment in their kilns with success if 

 steaming is done, and if they do so how the wiring is constructed. 

 Many thanks in advance from The Electrician. 



Answer to Question 7 

 The writer of the answer to your tale of trouble has built many 

 dry kilns of the type which you so clearly indicate, and also happens 

 to have a good understanding of electrical construction. Do not 

 blame the kiln operator too much for wishing to have good per- 

 manent lights at both ends of his kilHs. He needs good light there 

 daily, and that he cannot always obtain from an Eveready hand 

 lamp, but he and the boss have overestimated the possibilities of 

 good electrical construction under a temperature of about 160° at 

 nearly 100 saturation. It simply can't be done. There are others 

 who have found out about it. According to your description you 

 have installed the job very well, and your judgment was correct 

 in advising against the expenditure, therefore it will be best to 

 forget the entire incident, unless you can fix up some plug outlets, 

 on the outside, in weatherproof boxes, one between each two kilns, 

 which will be very acceptable to the ojierator and will afford you a 

 sweet revenge. Cons. Engr. 



Question 8 — Temperature Difference Between Front and Rear of 



a Dry Kiln 



Some time ago the boss bought a new hygrometer with a fan 

 attachment, driven by a real motor, which can be driven from any 

 lamp socket by regular lighting current, and equipped with an 

 extension, long enough to reach any part of our compartment kilns 

 by passing this extension along the rails and under the kiln doors. 



I have made many tests with this hygrometer in different loca- 

 tions within the kilns, allowing from four to eight minutes each 

 time for the instrument to adjust itself to the true temperature 

 and moisture conditions, and I find a surprisingly great difference 

 between the front and the rear ends of some of our eoriipartment 

 kilns. In some of these both bulbs show from 4 to 9 degrees lower 

 temperature at the rear end, although the heater coils seem to be 

 warm all over. 



Could it be that the incoming steam radiates more heat at the 

 front end, where it enters the heater coils f What can I do to 

 equalize the temperature and humidity at both ends of these kilns? 



Mac. 

 Answer to Question 8 



Your employer very evidently has made a very good investment 

 by giving you an instrument worth while, thereby inducing you to 

 investigate. If you continue you will discover a good many inter- 

 esting things about your dry kilns, and return the cost of the 

 hygrometer manyfold. 



Your judgment in giving the machine from four to eight minutes 

 in a location before reading is strictly correct. It does take about 

 that long, even with a good motor fan driving the air over the bulbs, 

 before the mercury has equalized to surrounding temperature. 



Now as to the temperature difference between the front and rear 

 of the compartment kilns. This is a common occurrence. The 

 steam can be hotter at the inlet end of the coils only if the inlet 

 connections are not large enough to supph' the amount of steam 



35 



Where does the ! 

 moist, warm air go? 



Up and around, in and out, over 

 every usable inch of every stick in 

 the Kiln. It's the only way to dry 

 lumber properly and the only way 

 to lessen degrade and more profits 

 for 3'ou. And the 



Slurfevanl 



HIGH HUMIDITY DRY KILN 



The Kiln with a riiciilalion you can understand 



is the only Kiln that will do this right 

 because the circulation of this moist, warm 

 air is positive and complete. No guess- 

 work, no "trusting to luck" with accurately 

 controlled circulation, re-circulation, tem- 

 perature and humidity. 



Circulation is the nub of the wonderful re- 

 sults wherever Sturtevant Kilns are in- 

 stalled. AVrite for Catalog No. 282. 



B. F. STURTEVANT COMPANY 



HYDE PARK BOSTON MASSACHUSETTS 



