REVENUE RECOGNITION - Schedule of Net Sales from Contracts with Customers by Market Sector (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 47,364	$ 40,324	$ 136,269	$ 113,059
Aerospace & Defense
Disaggregation of Revenue [Line Items]
Net sales	27,945	24,598	81,761	66,705
Medical
Disaggregation of Revenue [Line Items]
Net sales	13,262	8,871	35,430	24,873
Industrial
Disaggregation of Revenue [Line Items]
Net sales	6,157	6,855	19,078	21,481
Point in Time
Disaggregation of Revenue [Line Items]
Net sales	24,356	21,084	68,676	57,454
Point in Time | Aerospace & Defense
Disaggregation of Revenue [Line Items]
Net sales	14,263	11,300	40,639	30,950
Point in Time | Medical
Disaggregation of Revenue [Line Items]
Net sales	4,886	5,127	12,618	12,441
Point in Time | Industrial
Disaggregation of Revenue [Line Items]
Net sales	5,207	4,657	15,419	14,063
Over Time
Disaggregation of Revenue [Line Items]
Net sales	23,008	19,240	67,593	55,605
Over Time | Aerospace & Defense
Disaggregation of Revenue [Line Items]
Net sales	13,682	13,298	41,122	35,755
Over Time | Medical
Disaggregation of Revenue [Line Items]
Net sales	8,376	3,744	22,812	12,432
Over Time | Industrial
Disaggregation of Revenue [Line Items]
Net sales	$ 950	$ 2,198	$ 3,659	$ 7,418