Recently I recorded a quick little video to show you how to customise your extended base to fit perfectly & firmly on your A1 quilting machine.
Step 1: Loosen the 4 screws holding the side plates on the base
Step 2: Place the extended base on your machine by sliding it over the hopping foot using the channel in the base. Place the thumb screws in the slots of the side plates in the tapped holes & tighten them firmly.
Step 3: Adjust the base to be centred on the base of your machine. There are slots in the side plates to allow this whilst those screws are still loose.
Step 4: Tighten the 4 screws with wingnuts to keep everything firm & in place. This will provide an excellent stable base whilst using rulers with your A1 Quilting machine.
Once this has been done, you will only ever have to loosen the thumb screws to remove & replace your extended base.