And now for the portholes!
I must confess, this episode is so embarrassing I had decided not to include it - but then reminded myself that the main reason for posting this thread is that anyone reading it can learn from my mistakes.
I had cut holes to fit the white metal castings, planning to make brass replacements with the same diameter. However, the discovery that these could be bought from modelbox.info for 92p each (+£2.50 del.) resulted in a considerable saving in time and labour.
I felt that they needed to be removable as I did not intend to paint them and they might, at some stage, need re-glazing (the deckhouse walls are not removable because of the steering chain). Perhaps the most obvious fixings would be simulated rivets but the chap in the drawing office thought that securing them in the 1.5mm ply of the deckhouse wall might be difficult. The next thought was hex head bolts. As the holes in the rims were 1mm, 14 BA were considered but the heads were too big. (They looked too big and there was insufficient clearance to get a nut-spinner over them.) 16 BA ones were purchased and they looked OK.
Now for the problems!
The new portholes had a diameter of 14.9mm and the holes I had made for the castings were 15.9mm! My initial reaction to this was that I just needed to glue in an insert but this was when I was planning to use 14 BA bolts (and I have a 14 BA tap). When the 16 BA bolts arrived on the scene (and not having a 16 BA tap), there was nothing for it but to hand the problem over to the chap in the drawing office!
He designed a flanged sleeve to secure nuts on the inner surface - which, on paper, impressed his underling. All he had to do was make it - what could be simpler?
Acrylic material was chosen because it would form a solvent weld with superglue when embedding the nuts and would also make a good bond with the deckhouse wall. The lack of any round stock large enough meant wastefully turning down a rectangular block but hey-ho off we went. All a rather delicate operation but we managed to get a pair, each with six wells which were a gentle push fit for the nuts.
The next stage was significantly influenced by the fact that I am sensitive to superglue so I needed to glue the nuts in, keeping them aligned vertically, in the garden with a fan blowing and keeping my nose at a safe distance!
A successful experimental run was performed with the nut held right at the end of a bolt and secured against a PTFE sleeve.
The bolt could be unscrewed from the embedded nut (i.e. hadn‘t got glued in!) so the main task was embarked upon. I started alternating between the rings and the first three went OK
The fourth one, however, proved difficult to push in and the cyano was going off, so I pushed harder and:
I thought “Oh bother” (or something very similar). Time for a rethink - which resulted in the thought: The problem would be easily solved if I had a 16 BA tap. My experience with small size taps has not been happy (I have three 12 BA taps, all of which produce over-sized holes - the worst being the one I paid most for). However, the 14 BA one, which was cheap, performs well so, after seeking permission from the Management, I bought a 16 BA jobbie from Eileen’s Emporium for £20 (+£4 p&p). It performs excellently!
So now, all I had to do was make a couple of spacer rings, glue them into the deckhouse walls, drill the holes and tap them out.
I had to make this little nut-spinner as a normal one is too chunky.
I know, I know - I can hear you asking “Why on earth didn’t he do it that way in the first place?”.
I blame the chap in the drawing office - he definitely needs putting out to grass!
Coming shortly - an episode where everything went well!!!!!!
Mike