I use an upright hammer extractor to remove the old checks and wires. If the head pulls off too often turn them all up side down and put CA glue in the check holes and let it set. They will all extract nicely then. Height is a function of tail length and shank height. Look to have the backcheck the same height as the top of the shank when height properly set and the top of the check is slightly below the tip of the tail when at drop. Use a backcheck turner in the drill press, set the key in the vise at about 68 degrees (check the angle of the hole) and set the quill stop to place the check at the height determined the push them all in the same height. Hammering them in can split the key and/or the check block. More details as needed, just write. Newton
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