Oxy does not feed into the flame

I have a Smith Jewelers torch.Oxy/Acy Oxy true handpiece (One tank
One regulaor type). After 30 yrs of use. and adding a new tank. I
have trouble getting a sharp blue flame. The Gas just pours out and
doesn’t seem to mix at all. I have opened it up slowely and to
various pressures. I have had my hand piece serviced and the
regularor serviced by a tech. torch specialist in Portland Or. I
sent each piece to be repaired alternately after having this problem
2 months ago.I had repairs done through Air Gas a local dealer I use
for Fuel cell refills. I hooked everything up yesterday after 6
weeks of repair down time and I still have the same problem… The Oxy
does’t seem to be feeding into the flame I still can not get a a
sharp blue controlable flame. Any suggestions? I have a little torch
and am using it for everthing… in the meantime. can anyone trouble
shoot,or have any suggestions? Please ? Thanks, B.K.

p.s. I teach Jewelry working every weekend I need my second torch for
backup… for larger sheet projects such as belt buckles, Sweat
soldering etc…

clean the small brass filter in the handpiece and if that doesn’t
cure it replace the filter entirely. your air gas mixer is the second
place to clean. and if that doesn’t do it, time to replace the nit
and get a refund from the repair work that apparently didn’t do the
job it was supposed to do…