Schedule of Segment Reporting Information, by Segment (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017		Mar. 31, 2016	Dec. 31, 2016
Net sales	$ 9,483,327		$ 9,596,395
Depreciation	303,197		299,355
Segment operating profit	1,437,167		1,659,560
Selling and adminstrative expenses	(680,928)		(685,262)
Interest income	14,683		8,759
Capital expenditures	177,314		599,381
Accounts receivable, net	6,173,784	[1]	6,111,917	$ 5,323,519	[1]
Inventories, net	5,287,442		4,919,704	4,537,693
Property, plant and equipment, net	12,324,675		11,998,469	$ 12,450,558
Other assets	7,956,280		7,418,596
Fastener
Net sales	8,736,188		8,447,329
Depreciation	269,837		260,823
Segment operating profit	1,191,547		1,226,361
Selling and adminstrative expenses	0		0
Interest income	0		0
Capital expenditures	174,789		409,785
Accounts receivable, net	5,797,234		5,701,331
Inventories, net	4,075,856		3,951,985
Property, plant and equipment, net	10,187,799		9,858,184
Other assets	0		0
Assembly Equipment
Net sales	747,139		1,149,066
Depreciation	24,390		21,582
Segment operating profit	245,620		433,199
Selling and adminstrative expenses	0		0
Interest income	0		0
Capital expenditures	2,525		181,368
Accounts receivable, net	376,550		410,586
Inventories, net	1,211,586		967,719
Property, plant and equipment, net	1,542,837		1,628,796
Other assets	0		0
Unallocated Corporate
Net sales	0		0
Depreciation	8,970		16,950
Segment operating profit	0		0
Selling and adminstrative expenses	(680,928)		(685,262)
Interest income	14,683		8,759
Capital expenditures	0		8,228
Accounts receivable, net	0		0
Inventories, net	0		0
Property, plant and equipment, net	594,039		511,489
Other assets	$ 7,956,280		$ 7,418,596

[1] Net of allowance of $150,000.