5. INVENTORIES (Details) (USD $)	Jan. 31, 2015	Apr. 30, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 3,105,000	$ 2,370,000
Work-in-process	3,043,000us-gaap_InventoryWorkInProcess	3,160,000us-gaap_InventoryWorkInProcess
Total inventories	$ 6,148,000us-gaap_InventoryNet	$ 5,530,000us-gaap_InventoryNet

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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-Name Accounting Standards Codification

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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