At most of you know, I have been fighting to keep enough air moving and frequent and heavy cleaning has worked for a while and then not so much, , we can see the laser firing even if there is much dirt on it and I was thinking that the same might be true of the exhaust.
I generally keep an eye out for things that are close to 4 inches in diameter both for bending wood and making a quick release to unplug and get at the exhaust. a while back I found that the smaller Folgers coffee can was just a bit smaller than the 4" exhaust hose and makes a nice plugin fitting but I really wanted to see what was happening in real time while it was working. I picked up an endoscope but have not as yet got it working. but I discovered that the 2 liter Soda bottles were just over the 4. I would have pictures of the process but as there were many restarts and blind alleys the story would only be a sad one.
So skipping all that you start with a 2 Liter Soda bottle and using scissors make a clean cut just beyond where it starts to curve. This is a kind of floppy cylinder that will not make a tight fit, but and this is a bit tricky an old Teflon pan heated and the cylinder pressed on gently and removed. the part heated will shrink in diameter rapidly and continue so till it cools completely. by taking it away from the heat and letting it cool slowly it will create a flat ring almost 90 degrees and now be too narrow to fit over the [orts. I had already made a flat ring to fit over the exhaust hose and I now use ca glue to hold it at the end of the now not at all floppy cylinder. however, the opening is now too small to fit, to solve this I use a punch and make many notches every half inch or enough that each little tab will give and bend both making tight-fitting hold but pointing out they resist being pulled off
The coffee insert was fitted with masking tape over foam tape to make a jam fitting and the same heating with notches at a much finer level makes the whole business look like so…
I have not experimented beyond this point but will post a follow up if there is a need. before putting it together I totally scrubbed all that I could reach and ran all the various cleaning regimens including the lenses and head fan that had again dragged to a stop.