Bolts - Hex vs Socket

[James Harvey]

Hi Guys

I've been wondering about this for a little while now... what are the merits of these two types of bolts? You obviously see both types on vehicles, but when would you choose one over the other?

I guess there's the fact that in confined spaces one type may be a little easier to access than the other, and the hex profile is smaller than the socket one. Are there any other reasons (I've tried google but not found much)? What's your bolt type preference?

Cheers
James

 

[Brett James-McCall]

James,
I guess for me it can come down to looks in some areas, or as you say serviceability later on, as long as it's not in a critical area.

At my local engineering suppliers, all their socket bolts are 12.9 (metric), whereas most of the normal bolts are at 8.8. Just the same as you use Grade 8 (imperial) bolts on flywheel, grade 5 on suspension (as long as sized correctly). So there is some reason behind usage in certain areas.

 

[Ron Earp]

Proper grade bolt to do the job first and foremost. I've cussed at more Allen headed bolts on race cars than anything else. Tools are more common for standard headed bolts, so unless there is an access reason that demands an Allen head I would not use one. And stay away from soft stainless steel Allen heads, they're just asking to be rounded off by a hamfisted crewman, or you on a bad day.

 

[Terry Oxandale]

Not mentioned, but ones I seem to use more frequently are 12-point cap screws. The heads are smaller than a hex, but less trouble than socket heads. The only drawback I've found is that you must have a set of 12-point sockets/box-ends for them.

 

[John]

And stay away from soft stainless steel Allen heads, they're just asking to be rounded off by a hamfisted crewman, or you on a bad day.

The trick ive learnt there Earl is always put a dab of silver "Never seize" on a stainless bolt or cap screw, and they wont Gaul on you.
cheers John

 

[Robert May Eng.]

I like the flange bolts and K nuts with the reduced sized socket head. No washers needed.

Bob

flanged bolts

Demon Tweeks Imperial Aerospace Locknut (K-Nut) - Demon Tweeks

 

[Ron Earp]

The trick ive learnt there Earl is always put a dab of silver "Never seize" on a stainless bolt or cap screw, and they wont Gaul on you.n

I like my trick of "Never Use" better....

 

[James Harvey]

Cheers guys - some interesting comments there. Thanks :thumbsup:

 

[Scott Calabro]

The trick ive learnt there Earl is always put a dab of silver "Never seize" on a stainless bolt or cap screw, and they wont Gaul on you.
cheers John

Yup, that works. Especially "Nuclear Grade."

One that works great in a pinch is plain old milk of magnesia, and to remove things, mouse milk. Both are really old school tricks taught to me by a Flying Tigers wrench. I miss that Dude, he'd probably forgotten more aircraft knowledge than I'll ever know.

 

[Alex]

I like my trick of "Never Use" better....

same here - I hate socket headed bolts with a passion.