Business Segments (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 01, 2017 USD ($)	Dec. 27, 2015 USD ($)	Jan. 01, 2017 USD ($) segment	Dec. 27, 2015 USD ($)	Jul. 03, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of segments | segment			2
Net sales	$ 97,399	$ 103,529	$ 197,766	$ 210,220
Gross profit	15,898	18,521	33,183	39,659
Selling and administrative expenses	12,953	14,340	26,336	27,964
Internal research and development expenses	533	438	884	951
Restructuring charges	0	2,360	0	2,360
Reversal of accrued contingent consideration		(1,530)		(1,530)
Operating income	221	454	1,553	4,952
Capital expenditures	1,451	1,783	2,570	3,263
Total assets	223,172	245,998	223,172	245,998	$ 245,998
Operating Segments | Manufacturing and Design Services
Segment Reporting Information [Line Items]
Net sales	67,382	67,586	132,384	141,543
Gross profit	8,357	6,989	15,651	17,285
Selling and administrative expenses	5,561	6,646	11,537	12,527
Internal research and development expenses	0	0	0	0
Restructuring charges		2,360		2,360
Reversal of accrued contingent consideration		(1,530)		(1,530)
Operating income	986	(2,524)	472	(183)
Capital expenditures	464	427	670	1,433
Total assets	151,020	167,277	151,020	167,277
Operating Segments | Engineered Components and Products
Segment Reporting Information [Line Items]
Net sales	32,350	40,642	69,942	78,731
Gross profit	7,541	11,532	17,532	22,374
Selling and administrative expenses	3,545	3,715	7,369	7,312
Internal research and development expenses	533	438	884	951
Restructuring charges		0		0
Reversal of accrued contingent consideration		0		0
Operating income	3,082	6,957	8,511	13,260
Capital expenditures	423	228	758	273
Total assets	63,143	69,627	63,143	69,627
Unallocated
Segment Reporting Information [Line Items]
Net sales	0	0	0	0
Gross profit	0	0	0	0
Selling and administrative expenses	3,847	3,979	7,430	8,125
Internal research and development expenses	0	0	0	0
Restructuring charges		0		0
Reversal of accrued contingent consideration		0		0
Operating income	(3,847)	(3,979)	(7,430)	(8,125)
Capital expenditures	564	1,128	1,142	1,557
Total assets	9,009	9,094	9,009	9,094
Eliminations
Segment Reporting Information [Line Items]
Net sales	(2,333)	(4,699)	(4,560)	(10,054)
Gross profit	0	0	0	0
Selling and administrative expenses	0	0	0	0
Internal research and development expenses	0	0	0	0
Restructuring charges		0		0
Reversal of accrued contingent consideration		0		0
Operating income	0	0	0	0
Capital expenditures	0	0	0	0
Total assets	$ 0	$ 0	$ 0	$ 0