Schedule of Segment Reporting Information, by Segment (Details) (USD $)	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012	Dec. 31, 2012
Net sales	$ 9,461,778		$ 8,537,639	$ 27,915,157		$ 26,167,158
Depreciation	270,870		251,364	801,689		743,650
Segment profit	1,681,812		1,169,681	4,293,715		3,535,253
Selling and administrative expenses	(539,643)		(504,524)	(1,601,772)		(1,559,115)
Gain from disposal of equipment	74,235			116,721		57,500
Interest income	7,801		8,185	23,286		24,870
Income before income taxes	1,224,205		673,342	2,831,950		2,058,508
Capital expenditures	785,371		66,626	2,760,320		580,032
Accounts receivable, net	6,248,403	[1]	5,453,193	6,248,403	[1]	5,453,193	4,577,932	[2]
Inventories, net	4,894,521		5,214,761	4,894,521		5,214,761	4,936,372
Net property, plant and equipment	9,988,018		7,731,907	9,988,018		7,731,907	8,077,866
Other assets	7,658,231		8,150,878	7,658,231		8,150,878
FastenerSegmentMember
Net sales	8,631,105		7,841,672	25,397,537		23,781,773
Depreciation	237,621		216,732	702,089		644,853
Segment profit	1,453,799		1,024,865	3,615,776		2,957,672
Selling and administrative expenses	0		0	0		0
Gain from disposal of equipment	0			0		0
Interest income	0		0	0		0
Capital expenditures	518,150		66,626	2,429,172		472,672
Accounts receivable, net	5,873,916		5,061,072	5,873,916		5,061,072
Inventories, net	3,994,869		4,392,211	3,994,869		4,392,211
Net property, plant and equipment	8,309,105		5,981,212	8,309,105		5,981,212
Other assets	0		0	0		0
AssemblyEquipmentSegmentMember
Net sales	830,673		695,967	2,517,620		2,385,385
Depreciation	14,050		14,725	42,150		42,975
Segment profit	228,013		144,816	677,939		577,581
Selling and administrative expenses	0		0	0		0
Gain from disposal of equipment	0			0		0
Interest income	0		0	0		0
Capital expenditures	0		0	59,863		68,203
Accounts receivable, net	374,487		392,121	374,487		392,121
Inventories, net	899,652		822,550	899,652		822,550
Net property, plant and equipment	1,124,031		1,122,542	1,124,031		1,122,542
Other assets	0		0	0		0
UnallocatedCorporateMember
Net sales	0		0	0		0
Depreciation	19,199		19,907	57,450		55,822
Segment profit	0		0	0		0
Selling and administrative expenses	(539,643)		(504,524)	(1,601,772)		(1,559,115)
Gain from disposal of equipment	74,235			116,721		57,500
Interest income	7,801		8,185	23,286		24,870
Capital expenditures	267,221		0	271,285		39,157
Accounts receivable, net	0		0	0		0
Inventories, net	0		0	0		0
Net property, plant and equipment	554,882		628,153	554,882		628,153
Other assets	$ 7,658,231		$ 8,150,878	$ 7,658,231		$ 8,150,878

[1] Net of allowance of $153,000.

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