Condensed Consolidated Balance Sheets (Unaudited) - USD ($)		Mar. 31, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents		$ 898,643	$ 1,152,569
Certificates of deposit		7,561,000	7,810,000
Accounts receivable, net	[1]	6,754,505	5,326,650
Inventories, net		4,596,678	4,528,100
Prepaid income taxes			84,112
Other current assets		339,131	357,918
Total current assets		20,149,957	19,259,349
Property, Plant and Equipment:
Land		923,587	923,587
Land improvements		611,847	611,847
Buildings and improvements		8,039,831	8,039,831
Production equipment and other		34,824,982	34,607,507
Property, Plant and Equipment Gross		44,400,247	44,182,772
Less accumulated depreciation		31,943,387	31,625,819
Net property, plant and equipment		12,456,860	12,556,953
Total assets		32,606,817	31,816,302
Current Liabilities:
Accounts payable		1,647,297	737,040
Accrued wages and salaries		659,681	674,316
Other accrued expenses		427,686	495,132
Unearned revenue and customer deposits		74,053	312,775
Total current liabilities		2,808,717	2,219,263
Deferred income taxes		723,084	737,084
Total liabilities		3,531,801	2,956,347
Shareholders' Equity:
Preferred stock	[2]	0	0
Common stock	[3]	1,138,096	1,138,096
Additional paid-in capital		447,134	447,134
Retained earnings		31,411,884	31,196,823
Less: Treasury stock	[4]	3,922,098	3,922,098
Total shareholders' equity		29,075,016	28,859,955
Total liabilities and shareholders' equity		$ 32,606,817	$ 31,816,302

[1] Net of allowance of $140,000.

[2] No par value, 500,000 shares authorized, none outstanding.

[3] $1.00 par value, 4,000,000 shares authorized, 1,138,096 shares issued, 966,132 shares outstanding.

[4] At cost, 171,964 shares.