Rob, the Roundhouse designer has gave me instructions for removing the smokebox from Karen. When Tag Gorton, editor of Garden Rail magazine tried to follow them, he foud it more difficult than it appears from my notes. Indeed he though that extra screw needed to come out and so phoned Roundhouse. It turns out that it needs a firm hand and confidence, but the instructions are correct. I have amended the notes, to reflect Tag's experience, and if you wish to ask him, then he is happy for you to email him on firstname.lastname@example.org
1. Remove the two screws holding the front buffer beam and remove it.
2. You will now see two cheesehead screws holding the smokebox to the chassis crossmember. Remove these and put them somewhere safe.
3. Now ease the smokebox and the complete front footplate forward until it stops. Then it needs a firm pull to release it and lift it up to clear the boiler and exhaust.
4. The Karen is fitted with a simple chuff pipe "enhancer". This needs to be removed to fit the Summerlands Chuffer as follows.
5. Place the smokebox on the footplate next to the exhaust and measure down 50mm down from the top of the chimney. Mark the exhaust pipe at that point. Protect the boiler and cut the exhaust with a Dremel or junior hacksaw, then clean up the end of the pipe with a fine file.
6. Push the SCGP1 Chuffer on to the exhaust - if at all loose, the slightest bend in the copper pipe will make it grip.
7. Now replace the smokebox/footplate and check that the chuffer is about 5mm down from the top of the chimney. Check also that the sound slot is away from the chimney wall (it is marked with a scratch on the top).
8. Replace the screws and buffer beam and you are ready to steam up and enjoy the sound!