Barryvabeach
>Dereck, I can't be of much help in that both of my SJBTC planes are fixed mouths, but Stephen Thomas has a series of three articles in The Home Shop Machinist (July, Sept, and Nov of 1999) in which he describes how he made an adjustable mouth smoother from a SJBTC kit ( the kit wasn't adjustable). He made a slot in the moveable plate to hold the head of a T nut, then it looks like a hex bolt comes down through the bun. It looks like you loosen the bolt, then manually adjust the moveable section from below, then tighten the bolt from above locking the moveable section in place. He noted that he had to silver solder a plate on the top of the casting to allow enough room to mill out the bottom for the plate and slot. If you have any specific questions, let me know, or call Bob, he apparently answers questions if you can get a hold of him. SJBTC also sells reprints of those issues.