Segment Reporting: Schedule of Segment Reporting Information, by Segment (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Net sales	$ 8,621,678	$ 10,011,641
Depreciation	336,389	326,520
Accounts receivable - Less allowances of $140,000	5,954,474		$ 5,529,307
Inventories, net	6,832,459		6,100,391
Net property, plant and equipment	13,827,889		$ 13,258,146
Fastener
Net sales	7,579,120	8,925,099
Depreciation	297,723	291,881
Segment operating profit	588,895	1,177,462
Selling and adminstrative expenses	0	0
Interest income	0	0
Capital expenditures	756,107	184,227
Accounts receivable - Less allowances of $140,000	5,500,631	6,420,410
Inventories, net	5,831,166	3,658,938
Net property, plant and equipment	11,184,576	10,175,256
Other Assets	0	0
Assembly Equipment
Net sales	1,042,558	1,086,542
Depreciation	28,924	27,298
Segment operating profit	336,074	384,185
Selling and adminstrative expenses	0	0
Interest income	0	0
Capital expenditures	124,000	31,495
Accounts receivable - Less allowances of $140,000	453,843	334,095
Inventories, net	1,001,293	937,740
Net property, plant and equipment	1,674,573	1,646,752
Other Assets	0	0
Unallocated Corporate
Net sales	0	0
Depreciation	9,742	7,341
Segment operating profit	0	0
Selling and adminstrative expenses	(593,402)	(676,939)
Interest income	36,275	27,080
Capital expenditures	26,025	10,705
Accounts receivable - Less allowances of $140,000	0	0
Inventories, net	0	0
Net property, plant and equipment	968,740	634,852
Other Assets	$ 6,192,967	$ 8,798,774