OK, I found some information, possibly what I used, I honestly can't remember it was several years ago:
https://www.cloudynights.com/topic/1...le-calculator/
Image as used on CN:
Original image as shown by
Mike I. Jones of Cloudy Nights
Another link which may be useful:
http://www.berfield.com/baffles.html
As for baffles, I believe from memory I had the perfect size tobacco tins a friend had given me and I cut the centres out as required based on the maths. I believe they sat in perfectly without any major need to secure them (they would be secured I just DO NOT remember) Did I mention I have an useless memory?
Two baffles and VERY rough photos.
This Tasco is modified beyond standard, Vixen 80mm ED lens cell, William Optics DDG Synta focuser (tube cut down to accommodate my design adapter), self made tube rings.
Sadly I don't really use it but while it's out now I should look into paint for the inner tube and throw it on a mount and take some lunar shots.
The original Tasco 17TR was bought new in the late 80s or early 90s from the only source I could find at the time for telescopes, some photography store. Luckily I had a pro photographer friends tax number and I saved on tax on anything related to photography (22% from memory), whether it was parts for a VHS I was fixing (though I did get asked what a VHS had to do with photography) to any lenses I could afford at the time.
GST RUINED that personal scam!