I show chamber work in several of my other videos. Metal mouthpieces but the tools and techniques are the same for hard rubber. Here is one: kzfaq.info/get/bejne/gruJZpaZzrKqXZ8.html

Thank you sincerely for your reply to my request for information concerning chamber enlargement. Yes I did see your video about modifying the metal mouthpiece. I am interested in enlarging the actual chamber of the old time mouthpieces of bakelite to arrive at something approaching the original Sax mouthpiece. There does not appear to be any source from which I may obtain actual dimensions of this monster type piece and the patent has just one rough drawing of the mouthpiece without any internal dimensions or other particulars to offer. Modifying the baffle or adding different types of baffles does not present any sort of real problem and metal mouthpieces do not have enough metal to even form a chamber. I have made metal mouthpieces and one wood piece so it would be merely a matter of obtaining the required internal and other dimensions to enable me to either make an entirely new piece or else modify existing pieces if they should have sufficient material on them. As there are many old time mouthpieces on hand and as the owners wish them modified to have as large chambers as possible, I thought it would be in my own interests to consult an expert such as yourself. If you could indicate or provide a source for the dimensions of the original Sax mouthpiece or something coming close to it, your assistance would be greatly appreciated and acknowledged. Thank you again and hoping to receive your assistance, suggestions, or advice.

I do not know where detailed info on the original sax mouthpiece could be obtained. Dr. Paul Cohen might know. He recently has played an original Sax restored by Music Medic using large chamber mouthpieces. I think he used a Buescher and/or Martin mouthpiece from his collection. Rascher and Caravan mouthpieces have similar designs. One think to look out for when making larger chambers is the intonation. To tune the mid range, you need to push them in farther to get the proper chamber volume needed for tuning. This then makes the palm key as sharper and/or bell notes flatter than when using medium chamber mouthpieces. This could fix an intonation problem or create one. It depends on the sax and the player's embouchure.

Thank you very much for your so speedy reply much appreciated. You are totally right about intonation. I sometimes use a Conn Eagle 75 and the tops are way out. But then the sound over the first two octaves is something to marvel at and enjoy. I have found that a vintage silver Selmer also behaves like this. I am not a professional instrumentalist and have picked up the sax because of the hundreds that must have been worked on by me over the fifty more years i have been into instrument refurbishing. I hate to ask further of you but perhaps you could let me know how i may contact Dr Cohen? Thank you most sincerely for your replies and i wish you the very best.

www.masongross.rutgers.edu/music/faculty/paul-cohen

Alvin Cornista My target for the facing length was 48 on the glass gauge (=24 mm). I got that from my experience in measuring a lot of mouthpieces. There are no good charts that give facing lengths. Even when I find a facing length spec my measurement of a mouthpiece rarely agrees with it.

MojoBari so the 48 is derived from the first feeler (which is actually 49 in your final chart) The theoretical Feeler of 0.0000 which reads facing length of 56 is not used as measurement? Wouldn't the 56 be the true length or am I missing something here? Appreciate your reply and much respect for your work

Sand down the table flat or tilt it a little the other way. Then reconstruct the facing curve. See my other videos.