Make them?
MDF in B&Q for £10 a sheet
Buy a cheap B&Q jigsaw for £20
Of all DIY projects, this couldn't be more simple!
that sheets going to be massive as these used to be my projects in the late 90'
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making speaker boxes for 12" pioneer sub woofers
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Oh the misses wouldn't approve as she threw away a whole roll of bubble wrap costing £80
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so mdf isn't something she'd cater for in the home!! As she threw away some not long back which would have been ideal doubled up.