Peter Insole
Western Thunderer
Thank you Tim T. I must admit that doing all this metallic knitting is pushing me to the limit. It might be a good time to take two tomorrow to come up for some air?!
Pete.
Pete.
Finescale - of a sort?!
- Thread starter Peter Insole
- Start date
Tim Watson
Western Thunderer
Completely agree Peter. It’s sometimes good to have a change from intensive modelling stuff. I had a very relaxing couple of hours painting a back scene this weekend.
Tim
Tim
Peter Insole
Western Thunderer
I must admit that while I do still enjoy playing around with plastic and ply, whittling wood and even mucking about with some metals from time to time, it is the completion rather than the process that gives me the greatest pleasure. There are some tasks that, after the initial excitement of discovery, now tend to fill me with dread at the prospect.
There will be a mightily jolly, happy chappie here when the final copper pipe is bent and installed... let alone the three remaining, downright awkward, tapered brass, ninety degree angled gauge glass valve levers!
Some new 6mm brass rod, of sufficient quantity and specifically ordered for the latter purpose had been delivered an absolute age ago, but I have never seemed to be in quite the right mind to do anything about it since... until now that is.
After a brief rest, I determined to get myself back to the business of mangling more non ferrous stuff:
Everything was going fine - if rather hard working with files in the usual manner - and apart from making a slip and accidentally removing a bit too much metal from one, (at the top in the above image) was fairly pleased with the finished shape.
It was just before reaching this point that I realised that there was a serious (and yet again self-imposed) design issue arising! I was terribly aware that I had to be absolutely sure that any resolution that might involve turning down any part of the levers in the valve area was properly sorted out before the fearful bending process was started!
The trouble was; I just couldn't quite make up my mind... so rather than taking a more considered, rational approach, decided instead to impatiently "throw caution to the wind", (actually, I used another expression!) and get the gas torch out!
"I'll sort it out when I get there" was a bit of a risk, but luckily it turned out alright! Also mercifully, two of the three bends worked, again amazingly without any anticipated breakages, (!) and the levers were eventually dropped, loose fitting, into the valve bodies to check their appearance:-
I had deliberately turned the tapered handles over long at first, primarily to provide sufficient leverage during the bend, but also because I will never trust a G/A to give accurate dimensions or proportions of detail parts... preferring to directly compare the article with photographs wherever possible.
As it turned out, I only needed to trim a mere 5mm or so off the ends to visually compare with my reference collection, whereas the original Horwich GA's suggested somewhat more required to be removed!
When I made the fittings around four years ago (?) I had concluded that as I had neither the tools or knowhow to make properly tapered and seated valves, a plain threaded bore would suffice. What I had completely failed to consider is that there would not only be far too much "slop" in a hand cut thread, but there was also a risk of accidental over tightening at the bottom end of the travel! The gauge glass bodies are of quite the same pattern as my recently completed steam brake, so at first I naturally assumed that doing these would simply be a repeat exercise - despite the presence of the pre-cut threads down the central hole in the male cap nuts.
On the prototype, the valve has the widest part of the taper at the top, lever end, while the narrow part is toward the enclosed base of the chamber. The bore of the cap nut can slide over the end (including the curve) of the lever, to then drop down and be tightened to retain the valve and lever.
Having already chosen smaller metric sizes suitable for a straight screw in from the top arrangement on the model, there was no way of even getting the cap over the head of the handle! This had not previously been a problem with the brake valve, as the handle in that instance was screwed down and locked from the top, so I was able to turn a collar as part of the spindle, and insert it from below the nut, prior to assembly.
I would have to come up with something completely different this time.
The little shoulder at the base of the new levers, at the point where it enters the cap nut and valve body, is representative of the genuine shaft diameter, but on the model is acting as a containment to prevent the lever from dropping down into the body, and I had roughly shaped the spindle below that shoulder to be a sliding fit in the existing cap, with allowance for a short projection below same.
With the otherwise completed levers in hand, I thought long and hard about the best way to deal with that bottom containment! I kept rejecting the notion of drilling a hole through the spindle for any sort of pin - mainly as that could be problematic if I then went on to use my preferred (and proven) wax filling method for providing a smooth, "feel" to the lever operation.
After much rummaging, I managed to find a length of K&S brass tube that was a perfectly tight, press home fit on one of the spindles, and a very slightly loose fit on the other! Having got that far, I weighed various ideas for locking these little collars, and plumped for yet another risky option: I reckoned that this would have to be the luckiest bit of soldering I have ever done, or at least could hope to have managed at any time previously?! I knew full well that I would have to be incredibly slick with both the amount of flux applied, and the briefest of touches with the solder wire to allow just sufficient wicking under the collar, but not enough to spread into the touching cap nut section beyond!
With a tremor present in both, but notably worse in my right hand, I have taken to holding the solder wire in the left, although I can't even trust that these days! I broke the habitual rule this time, and clamped the lever handle between two pieces of scrap wood in the bench vice, then wedged my hand by leaning against the vice to prevent any sudden movement. It made me a bit too close to the flame for comfort... but it worked a treat nonetheless!!
I apologise for not taking any pics of the progress, but I only remembered to take the last two images when I had finally got by breath back - and then only after cleaning up and shaping off the collars!
The tight one was tackled first - to hopefully build a little confidence... and it was fine. The slightly loose one was a heartstopper for a moment though! I had kept a spanner handy on the bench to quickly grab and twist the cap in the hope that I could keep it moving before the work cooled.
It was a frightfully close run thing that time, and I did feel the very slightest initial snatch of a drop of solder that had obviously crossed the minimal gap, but it has rotated perfectly freely thereafter!
Whewee!
I still have the gauge blow-down cock to do, but even as I was finishing with these two... my torch started puttering!
There was just enough gas remaining in the cannister to warm and pour the wax filling before the flame disappeared with a pop and a terrible pong!!
Pete.
There will be a mightily jolly, happy chappie here when the final copper pipe is bent and installed... let alone the three remaining, downright awkward, tapered brass, ninety degree angled gauge glass valve levers!
Some new 6mm brass rod, of sufficient quantity and specifically ordered for the latter purpose had been delivered an absolute age ago, but I have never seemed to be in quite the right mind to do anything about it since... until now that is.
After a brief rest, I determined to get myself back to the business of mangling more non ferrous stuff:
Everything was going fine - if rather hard working with files in the usual manner - and apart from making a slip and accidentally removing a bit too much metal from one, (at the top in the above image) was fairly pleased with the finished shape.
It was just before reaching this point that I realised that there was a serious (and yet again self-imposed) design issue arising! I was terribly aware that I had to be absolutely sure that any resolution that might involve turning down any part of the levers in the valve area was properly sorted out before the fearful bending process was started!
The trouble was; I just couldn't quite make up my mind... so rather than taking a more considered, rational approach, decided instead to impatiently "throw caution to the wind", (actually, I used another expression!) and get the gas torch out!
"I'll sort it out when I get there" was a bit of a risk, but luckily it turned out alright! Also mercifully, two of the three bends worked, again amazingly without any anticipated breakages, (!) and the levers were eventually dropped, loose fitting, into the valve bodies to check their appearance:-
I had deliberately turned the tapered handles over long at first, primarily to provide sufficient leverage during the bend, but also because I will never trust a G/A to give accurate dimensions or proportions of detail parts... preferring to directly compare the article with photographs wherever possible.
As it turned out, I only needed to trim a mere 5mm or so off the ends to visually compare with my reference collection, whereas the original Horwich GA's suggested somewhat more required to be removed!
When I made the fittings around four years ago (?) I had concluded that as I had neither the tools or knowhow to make properly tapered and seated valves, a plain threaded bore would suffice. What I had completely failed to consider is that there would not only be far too much "slop" in a hand cut thread, but there was also a risk of accidental over tightening at the bottom end of the travel! The gauge glass bodies are of quite the same pattern as my recently completed steam brake, so at first I naturally assumed that doing these would simply be a repeat exercise - despite the presence of the pre-cut threads down the central hole in the male cap nuts.
On the prototype, the valve has the widest part of the taper at the top, lever end, while the narrow part is toward the enclosed base of the chamber. The bore of the cap nut can slide over the end (including the curve) of the lever, to then drop down and be tightened to retain the valve and lever.
Having already chosen smaller metric sizes suitable for a straight screw in from the top arrangement on the model, there was no way of even getting the cap over the head of the handle! This had not previously been a problem with the brake valve, as the handle in that instance was screwed down and locked from the top, so I was able to turn a collar as part of the spindle, and insert it from below the nut, prior to assembly.
I would have to come up with something completely different this time.
The little shoulder at the base of the new levers, at the point where it enters the cap nut and valve body, is representative of the genuine shaft diameter, but on the model is acting as a containment to prevent the lever from dropping down into the body, and I had roughly shaped the spindle below that shoulder to be a sliding fit in the existing cap, with allowance for a short projection below same.
With the otherwise completed levers in hand, I thought long and hard about the best way to deal with that bottom containment! I kept rejecting the notion of drilling a hole through the spindle for any sort of pin - mainly as that could be problematic if I then went on to use my preferred (and proven) wax filling method for providing a smooth, "feel" to the lever operation.
After much rummaging, I managed to find a length of K&S brass tube that was a perfectly tight, press home fit on one of the spindles, and a very slightly loose fit on the other! Having got that far, I weighed various ideas for locking these little collars, and plumped for yet another risky option: I reckoned that this would have to be the luckiest bit of soldering I have ever done, or at least could hope to have managed at any time previously?! I knew full well that I would have to be incredibly slick with both the amount of flux applied, and the briefest of touches with the solder wire to allow just sufficient wicking under the collar, but not enough to spread into the touching cap nut section beyond!
With a tremor present in both, but notably worse in my right hand, I have taken to holding the solder wire in the left, although I can't even trust that these days! I broke the habitual rule this time, and clamped the lever handle between two pieces of scrap wood in the bench vice, then wedged my hand by leaning against the vice to prevent any sudden movement. It made me a bit too close to the flame for comfort... but it worked a treat nonetheless!!
I apologise for not taking any pics of the progress, but I only remembered to take the last two images when I had finally got by breath back - and then only after cleaning up and shaping off the collars!
The tight one was tackled first - to hopefully build a little confidence... and it was fine. The slightly loose one was a heartstopper for a moment though! I had kept a spanner handy on the bench to quickly grab and twist the cap in the hope that I could keep it moving before the work cooled.
It was a frightfully close run thing that time, and I did feel the very slightest initial snatch of a drop of solder that had obviously crossed the minimal gap, but it has rotated perfectly freely thereafter!
Whewee!
I still have the gauge blow-down cock to do, but even as I was finishing with these two... my torch started puttering!
There was just enough gas remaining in the cannister to warm and pour the wax filling before the flame disappeared with a pop and a terrible pong!!
Pete.
Last edited: