grumpy,
Thanks for your suggestions. As the no. 34 is stamped on the base of the jet block, I am presuming that this indicates a 0.34 mm dia jet. By eye, it would appear somewhere in that region. So I have ordered a pin vise and jet drill set from ebay, as many seem to contain a 0.30 dia drill. All the oxy tip cleaner sets that I could find seemed to have approx. 0.45 mm as their smallest rod.
So, we shall see how we go. I have noted that some hobbyists drill out the offending jets, fill with solder, and bore out the solder with a jet drill of correct size. I hope it doesn't come to that. I will let you know how things turn out.
Thanks and regards,
mustang
