Why do manufacturers use hex socket (AKA Allen socket) fastners??

[Orionaut]

Sorry, this is just a frustrated rant, but, Well why??

VW are the worst.

IME Hex socketed fasteners only have a very limited ability to withstand torque. They strip out very easily.

They are only suitable for cosmetic applications. Not serious engineering.

Especially the smaller sized ones 5/6mm.

VW crank pulleys are a constant ballache. they always strip out (When you want to do the cam belts etc) and subsequently have to be drilled/chiselled. (Aggressive heat solutions are not always practical and don't always work anyway)

My latest grumble, trying to do a timing chain (How did manufacturers forget how to do timing chains properly anyway) on a VAG 1.2.

The timing cover is retained by a multitude of 5mm hex socketed fasteners.

Of course they have all been loctited too!

Most came undone (Though I had to use the oxy torch on 4 of them before they went)

But three will not go under any circumstances and will have to be drilled! (Including the really awkward one in a deep recess just above the crankshaft)

Probably half of the labour for this job is going to be down to undoing 3 sodding bolts!

Had VW used Torx headed fasteners this would be a non-problem!

(It also wouldn't be a problem if the fasteners were made of steel that was actually harder than cream cheese, but typically the steel used seems to be particularly low grade. (The tool should strip before the job IYSWIM))

Bah!

Rant Over!

 

[pepsilol]

+1. Half the time you see this stuff and you think they're just doing it for a laugh.

My biggest grip is manufacturers changing up bolt sizes randomly. At one point it's all 16 and 18mm then they will chuck in a 19mm for no apparent reason.

 

[Orionaut]

+1. Half the time you see this stuff and you think they're just doing it for a laugh.

My biggest grip is manufacturers changing up bolt sizes randomly. At one point it's all 16 and 18mm then they will chuck in a 19mm for no apparent reason.

Oh yes.

Do you remember when the French frequently used M7 AF (Thread size rather than hex size)

Even commercial factors thought I was bonkers when I asked for a box. (rather than paying the grossly inflated prices from the dealer)

I am minded of the "Fergie" tractor tool kit.

A single spanner!

IIRC, 1/2W one end and 3/4W the other.

There were grooves on the spanner.

If you dipped the 1/2W end (The 3/4 end wouldn't fit) down the fuel filler the grooves would tell you how many gallons you had in the tank!

THATS the way to do it!

 

[Scania]

I agree entirely with you OP.

Doing the cam position sensor on my e39 was an absolute **** of a job, in the main due to the hex nut holding it in place and the difficulty in getting at it with a key.

Its not just car manufacturers though, Scania HGV's use them too, the fitters at work bemoan this fact continually!

 

[Aod]

Only time I've ever stripped an undamaged Hex head or hex-socket fastener is when I've used an incorrectly sized tool.

Are you sure you're using metric hex-tools and not imperial?

 

[Will Gill]

Agree with you 100% either the correct sized bit rounds off or the nut does, it's beyond annoying.

 

[Scania]

Only time I've ever stripped an undamaged Hex head or hex-socket fastener is when I've used an incorrectly sized tool.

Are you sure you're using metric hex-tools and not imperial?

Whilst I probably would use the wrong tools ,the fitters at work don't and have more Snap on (and other sets) than I could possibly know what to do with yet they still hate Hex with a passion!

 

[Orionaut]

Whilst I probably would use the wrong tools ,the fitters at work have more Snap on (and other sets) than I could possibly know what to do with yet they still hate Hex with a passion!

Insert <Slow nodding smiley> here!

(As an aside, the smiley's are a bit limited here, Is there a reason for this?)

 

[Scania]

(As an aside, the smiley's are a bit limited here, Is there a reason for this?)

I've long thought this.

We need many more (doesn't mean they have to be used) but variety is the spice of - forum / life!

 

[JRS]

My biggest grip is manufacturers changing up bolt sizes randomly. At one point it's all 16 and 18mm then they will chuck in a 19mm for no apparent reason.

Heh, that's nothing. My dearly departed Oldsmobile had a mix of metric and imperial from the factory. That was a right pain in the rear. Project Bentley is similar, but it's never that certain whether it's a factory ****-up or a past maintenance ****-up....

Dad's Fiat Barchetta by comparison is brilliant. Everything is metric, and everything is Torx.

 

[adam cool dude]

I love working on my recently acquired Saab. All Torx bits . They also have nice little touches like making the nuts one size smaller than the bolts.

Manufacturers do not give a monkeys about ease of repair. It makes them more money if you have to drop the engine to carry out simple tasks.

 

[kaiowas]

Manufacturers do not give a monkeys about ease of repair. It makes them more money if you have to drop the engine to carry out simple tasks.

It actually doesn't. The dealers make money off repairs, the manufacturer doesn't. In fact any work the dealer does under warranty is then billed to the manufacturer so the manufacturer end up paying more if the job is more complicated.

 

[Orionaut]

It actually doesn't. The dealers make money off repairs, the manufacturer doesn't. In fact any work the dealer does under warranty is then billed to the manufacturer so the manufacturer end up paying more if the job is more complicated.

Indeed,

Which simply makes such obviously crap design even more baffling.

The only other explanation is that, in the past, manufacturers got old cars off the road (And therefore ensured a market for the new ones) by not bothering to paint the bits you couldn't see.

(Back in the 70's most cars would have undersides like colanders by the time they were 8 years old)

They cant get away with that any more so now the trick is to design in "Features" that will ensure that problems that might arise when the vehicle is 10 years old or so will be deemed too awkward and expensive to repair.


(Mind, the tendency not to paint the bits you cant see seems to be returning. there are a lot of new vehicles out there with very little under-body protection these days)

 

[sovietspybob]

I guess i've been lucky in my choice of cars thus far as everything has been metric bolts on my cars.

The wifes old Clio 197 however was a nightmare to work on compared to all the Japanese cars ive had.

 

[pepsilol]

Japanese cars are amazing to work on. They are really thoughtful. The LS430 timing belt I did was done with such ease.

Honestly, every bolt on the front was the same size, nice drain cocks, logical layout, it was so beautiful the job was done in 2-3 hours.

 

[Akagi]

I couldn't agree more, my car is riddled with the poxy things!

It took far longer than it should have to take the front off of my car due to these things stripping out... I have a bag of spare ones.

Your comparison with cream cheese made me chuckle, it seems pretty darn accurate. A couple of ballsed up turns and they are quickly turned into something which looks like a rivet.

 

[InvaderGIR]

Not had an issue with hex stuff unless I've been a muppet really. Rounded some due to not fully inserting the hex key, but bashing them home fully, even on 'rounded' ones has sorted them as it's usually only the edge that's rounded. You lot fail at cars/mechanics.

 

[adam cool dude]

I guess i've been lucky in my choice of cars thus far as everything has been metric bolts on my cars.

The wifes old Clio 197 however was a nightmare to work on compared to all the Japanese cars ive had.

Indeed my friend had a Twingo 133 that I used to service for him. Removing the whole scuttle panel just to change a set of spark plugs!

 

[Akagi]

That said now I come to think of it, the damage is mainly caused when you find that the one you are trying to unscrew is now randomly a size larger than the last one, and you use the wrong size bit at first.

They aren't so bad if you put the right size in right from the off.

Oh, as a side note, even my sump plug has a hex fitting. That confused the hell out of me the first time I changed the oil.

 

[dalin80]

Triangles, squares, pentagon, hex, Allen, torx, ribes, splines and male and female versions of all of them. What fun it is to be a mechanic!

Even better is the average french piece of junk will have one of each all holding the same component in!