Please give us an ultimate blueprint which is confirmed by your client, and use red colour to mark those specifications which our last time samples are not correct. And also specify the tolerance. Then we will make samples strictly according to the blueprint. (you said that the helix angle of our samples are not right, please give detailed specification. Also you mark "R" on the thread bottom, you need to tell us how many mm is the R. And so on). We needn't original tap(as it's different from the blueprint), we just do as the blueprint shows.