QUANTUM PHYSICS

In another life I read quantum physics. It was a walk in the park compared to comprehending all the permutations of different thread types. I have previously posted about the multitude of sizes, threads and finishes for the fasteners on this machine and now I’m at the stage of gradually reassembling the component parts back onto the mainframe I have discovered yet another thread type. The Villiers engine and the bolts holding the engine through support brackets to the frame as well as the clutch mechanism use BSCy (British standard cycle) thread at 26tpi* which I had-visually- assumed in my ignorance to be BSF (20tpi) and bought accordingly.  Despite fixing many bikes in my youth and much to my shame I never realised that BSCy threads even existed. Apparently this thread type is used where constant vibration could loosen a courser thread.  Anyway I’m not going to ‘spoil the ship …’ by using the rusty and badly corroded old nuts so, contrary to my previous post, I have once again had to order new ones online and in the meantime turn my attention to other assembly jobs.

*Footnote. Isn’t the computer wonderful.  With the aid of a huge magnifying glass I counted 13 teeth over half an inch of the bolt thread and simply entered ’26 tpi’ into google and up came the answer –cycle thread. How did we manage before the internet ?

NOT IF, WHEN.

It had to happen eventually. During dismantling every single fixing or group of fasteners were placed in polythene bags and labelled with their identity and location on the machine, not least so I knew what quantity/size/thread replacements to buy. Now I’m reassembling the component parts onto the mainframe I’m missing the two bolts holding the roller shaft bearing brackets to the frame. Obviously they’re somewhere but after an hour of searching I gave up and ordered a couple of new ones online. They are ½” BSW x 11/4” round head coach bolts and although no longer obtainable in imperial the near identical metric equivalents are plentiful. 

Update. Sods Law. Within minutes of buying replacements the old ones were found !   I know what’s going to happen next, it occurs on every restoration I’ve ever undertaken. When the project is fully finished there’ll be a widget, grommet or something left over in the parts box with no obvious ‘home’ ! 

The old Atco transfers on the machine were removed as each part was prep’d for painting. Those on the petrol tank and fan cowling came off with ease; they looked like they had been stuck on and then painted over by someone whilst intoxicated so could not have been original.  In contrast the Chas. H Pugh transfer on the tool box just couldn’t be shifted without sanding back the lid to bare metal – that was original. 

CHAINSORE

The three drive chains were in such a bad state that I had fully expected to buy new. They were rusty, partially seized and full of crud.  I had assumed that a chain was a chain was a chain but the number of types and sizes is bewildering coupled with inconsistencies in the way suppliers use varying reference numbers or names to identify different sizes and types. Anyway as I’m keen to restore rather than buy new wherever possible I thought I would do my best to clean up these chains. They were first soaked with Gunk followed by neat washing up liquid, thoroughly scrubbed and then all the individual links were methodically cleaned up with the rotary wire brush attachment on my bench grinder. (Don’t try this at home folks, very sore fingers despite wearing thick leather gloves.) Finally they were buffed up with an emery pad and sprayed with oil. Although this task took several hours the end result is indistinguishable from new. All I have to do now is to remember to fix these chains onto the drive cog wheels prior to assembly.

WHAT A PLONKER

This week I assembled the engine and fuel tank mounts between the engine support brackets and then onto the frame. It was important to get all the various parts assembled in the right order and once again it was a case of consulting the video at every stage. Unfortunately when the machine was videoed both prior to and during dismantling some of the rear view assemblies were obscured by the tool box so putting everything back in the right order on the rear ½” bars connecting the engine side brackets to the frame support arms was trial and error. Hopefully I’ve got it right, I’ll soon find out otherwise.

At either end of this bar are the brackets to support the tool box- not the frame stay clips but the flat supporting brackets.  Not for the first time a component has disappeared into the ether and is nowhere to be found after an hour of searching.  Fitting the tool box will be one of the last jobs so if they don’t turn up I’ll make new.

Update. I could easily have deleted that previous paragraph but I’ve left it in just to show what a plonker I have been.  The tool box support brackets (arms) form part of, and were fitted to, the handle assembly weeks ago which has been stored in my office a couple of feet away from my keyboard !

JUMBO JIGSAW

I’m making progress far quicker than expected and with the paint now thoroughly dry I have been putting parts back on the main frame assembly. I would defy anyone who is not familiar with this mower to reassembly all these frame parts in the right order and on first attempt. When dismantling I made a sketch and list of the parts and most importantly the sequence in which they were removed, plus of course the video. Despite continually consulting this list and video I twice had to change parts over –especially the cross bar sleeves - that had been wrongly placed. At the risk of labouring the point videoing during dismantling was the best decision I made in this project. Invaluable.

WHAT A GRIND

This mower has several cross bars with 3/8 or ½”  BSW threaded ends. Inevitably over 80 years the exposed ends of these bars have taken a few knocks causing damage to the thread especially the bar through the front rollers. The new brass nuts I’ll be using can be screwed on with some effort  but being a softer metal than the steel bar this can causes cross threading in the nut  so this week I’ve been grinding down the ends of the bars just sufficient to reach clean thread. The nuts now spin on with ease.

MOHAMED COMES TO THE MOUNTAIN

I have many tender plants in my garden which will soon have to be overwintered in the garage. In addition to those indoors I have a multitude of mower parts spread all over the garage floor, walls and hanging from the ceiling and most of these will have to be put together into sub assemblies to clear floor space for the plants.  So this week I started loosely reassembling various sections.  Never having been very good at puzzles it’s fortunate that I have videos of all these assemblies on my computer.  I can’t take my computer into the garage so all the parts have been transferred indoors for assembling Blue Peter style whilst simultaneously watching the videos. Mrs Grass was so pleased !