Sunday, November 1, 2020

Thwarted at every turn!

There are two big projects at the moment. One is the brakes and the other is the sheet of steel over the back window. Both were thwarted today by different problems.

The primary plan was to install or to work toward installing the sheet of steel over the last back window. The plan was to drill locating holes and then trim the steel before final painting. Looking at the sky rain was clearly not far away. Today was therefore a day for at least slapping a coat of paint onto the sheet of steel - which I did. The paint came out lumpy being at the end of the can of paint. That didn't matter though. The biggest lumps got flicked away but plenty more remain. The best that can be said is that the panel is both painted and textured. At the end of the day there are so many imperfections in my paintwork on the bus that it's clearly done by somebody that just wanted to change the color of the bus without throwing money at fancy prep work or anything else. All I care about is that the bus looks decent from 20 feet away. Nearer, I just don't care. The law says it cannot be yellow so it's grey.

Having slapped paint on the panel I turned to the brake lines. In contrast to the paintwork, these I am extremely fussy about. They have to be right and there is no half-way, quarter way or most of the way. They have to be spot on. Doing it myself I'm learning a lot and will be able to do this kind of maintenance on the road.
The brake line I did the other day looks pretty good though the line did slip a little. Today I made up the second line to go from the flexible hose to the chassis since I seem to have to replace both lines simultaneously. The line slipped and did very little else. Thus it was time to practice a little. 
Having cut several practice pieces and had them all slip in the flaring tool it was time to re-evaluate the flaring tool. That's where all the fun began!
The flaring tool (from Harbor Freight) looked to have a 5/16 bolt. The problem with the existing bolts is that despite the T bar on them it's impossible to get them tight enough by hand. As there's no hex head on the bolt, they cannot be tightened with a wrench. Trying a 5/16 bolt found it was a tight fit and met resistance after the first half turn which is the tell-tale sign that the thread pitch is wrong.
Out came the Russian thread gauge and the thread came up as being a 20 TPI thread. That was pretty useful information.
Next I grabbed a digital caliper and found the bolt diameter was 7.6mm. That's where things began not to make much sense. There is no 20 thread per inch Imperial bolt of 5/16th. The 7.6mm was a very sloppy size for 5/16. That was a big puzzle.
Grabbing a micrometer and setting it to inches, the bolt came up at 0.3047 inches. Trying it again in metric came up with 7.67mm. The puzzle continued. 

Eventually after taking a thought break I pulled out the thread gauge again but instead of measuring with the threads per inch side, I used the metric side and came up with 1.25 threads. That's when the penny dropped. This was likely a metric thread.

Heading indoors I looked up the metric and imperial thread sizes and bolt gauges. It turned out that what I have is very likely a sloppy 8mm bolt since 8mm is very close to 7.67 mm and the thread pitch of 1.25 is exactly what an 8mm bolt should have. It's so handy having standards!

So the paint is still wet and drying on my sheet of steel, the sun has come out and the sky has cleared to deep blue but I can't work on the brake lines until I get some 8mm metric bolts to tighten the thing down firmly in order to prevent slippage.

As I work tomorrow and there's a covid epidemic I'm limiting my trips out so today is going to be a day of relaxation. The next time I work on the brakes will likely be Tuesday as there's an election and I have the day off due to the election.  
Rather than including caustic comments about any of the candidates for election, here's a picture of the brake line I made earlier today. This, I'm sure would make a much better President than any of those currently standing for election. Indeed, that simple brake line could easily replace every single politician in the world, costing less to keep while providing far more value.





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