I'd just like to say.........

[docc]

20 minutes ago, audiomick said:

I like Torx.

10 or 15 years ago they were a bit of a pain in the arse, because one didn't necessarily have the appropriate bit on hand. In the meantime, they have become so common here that the bit is available more or less as a matter of course.

The adavantage over a Phillips screw is that the driver is less likely to jump out of the screw head if you don't put enough pressure on it to stay in. When using a battery drill to screw in the screws, this is a major advantage. On the stages in theatres here, where set pieces are commonly screwed to the stage floor, and generally where things made of wood are screwed together, you nearly always see Torx here. As I said, I like them.

My understanding is this is exactly what the Phillip's head was designed for: for the driver to "cam out" on assembly without over-torquing.

They were never designed to take apart.

Agreed on Torx and Robinson drives being positive engagement, both in and out.

[audiomick]

43 minutes ago, gstallons said:

OOOOH , you need to Google Robertson screws .. 

 

Google can be avoided. There are Wiki articles that mention them.

For instance

https://en.wikipedia.org/wiki/Robertson_screw

They are uncommon here and in Australia, in fact I don't recall ever having seen one, but the idea sounds good.

 

25 minutes ago, docc said:

 positive engagement, both in and out.

What was that thing with having to leave town?

[Pressureangle]

1 hour ago, Lucky Phil said:

You need to pull down a modern car engine docc to properly understand how much of the design is about production line speed and ease of assembly and minimising machining. Terrible.

Phil  

I met a Man at a UAW local meeting once, about 1985. He was an engineer for Cadillac; salary somewhere in the mid-80,000's as I recall. His job? 

Find the shortest route for the fuel, cooling, and vacuum hoses. Co-ordinate that with the assembly line engineers to balance material costs with production costs. 

[Lucky Phil]

55 minutes ago, docc said:

My understanding is this is exactly what the Phillip's head was designed for: for the driver to "cam out" on assembly without over-torquing.

They were never designed to take apart.

Agreed on Torx and Robinson drives being positive engagement, both in and out.

Yes docc but don't confuse it with the superior JIS ( Japanese industry standard) cross head screw which the Japanese developed and use which don't cam out.

 

Phil

[Lucky Phil]

17 minutes ago, Pressureangle said:

I met a Man at a UAW local meeting once, about 1985. He was an engineer for Cadillac; salary somewhere in the mid-80,000's as I recall. His job? 

Find the shortest route for the fuel, cooling, and vacuum hoses. Co-ordinate that with the assembly line engineers to balance material costs with production costs. 

Yep I often see on car forums guys that remove stuff from cars because "they aren't needed". The fact is every car and bike is designed down to the last cent and unless there is a big customer appeal issue then it either doesn't get incorporated OR it's just enough to do the task. My FIL worked at the GM test ground here for over 40 years testing and developing new cars and prototypes and I meet owners all the time that modify production stuff that they spent many many hours developing and think some backyard business that's R$D consists of a few hundred miles driving on public roads has it all covered.

The Supra has a 5 pound weight bolted to the chassis cross member near the diff. It's called a chassis damper. Whats it do? not sure but I could have an educated guess. Clowns remove them because it's useless and saves weight! My advice is that unless you know precisely what it does and have the knowledge of a chassis engineer then better to leave it installed because the bean counters at BMW won't have it there unless it's necessary. A five dollar saving on a chassis damper not fitted translates to probably a million dollars on the bottom line to BMW/Toyota. They wouldn't fit it unless it was necessary.

 

Phil   

[docc]

22 minutes ago, Lucky Phil said:

Yes docc but don't confuse it with the superior JIS ( Japanese industry standard) cross head screw which the Japanese developed and use which don't cam out.

 

Phil

Yes, indeed. The JIS "cross head screw" is not a "Phillip's Head."

I have re-cut all of my "cross-head" screw drivers to limit/eliminate "cam-out."

[LowRyter]

17 hours ago, Lucky Phil said:

Not sure about this. I've done a lot of work on McDonald Douglas A4G Skyhawks. Not much consideration for maintenance on that thing. 

Phil 

Nope.  The F4 was perhaps even a better example.   This is why since the '70's, design has focussed on reliability and maintainability.  

[Lucky Phil]

5 hours ago, LowRyter said:

Nope.  The F4 was perhaps even a better example.   This is why since the '70's, design has focussed on reliability and maintainability.  

Well the Germans were way in front of everyone. Part of the reason they used inverted V12 engines was ease of maintenance. On a ME109 for instance the crews could do most of the engine work from the ground without stands by simply opening the bottom engine cowls to access the engine top end where most of the maintenance items were. On a Merlin you were working from a stand 6 feet off the ground on top of the engine cowls. 

Phil

[docc]

Our air cooled, V-twin big block Guzzi are a good example of design based upon maintenance and reliability goals.    

The whole spineframe chassis, as well. The ease of wheel removal, brake service, and battery access is admirable, IMCO. Sure, there is that "tank off" thing for the air and fuel filters, but I've seen worse.