6.3mm SK 1/4” drive socket???

[ForrestT]

I found a deep well 6.3mm SK 1/4” drive socket going through some tools from a bulk buy. Gents, what uses a 6.3mm socket? Never seen one before. I’m not a mechanic. But I am very curious and like to learn what tools are used on what things. Thanks for the answer.
Forrest

 

[gigamel]

6.3mm is metric for 1/4"
Like 3.2mm is 1/8" and 20.8mm sockets are 13/16" (spark plugs)

Hose clamp screws are 7mm or 1/4" (6.3mm)
That is why I add an 1/4" socket to my metric 1/4" sets.

 

[619DioFan]

I had to google that size to see for myself and yep a few companies make them . never encountered a 6.3mm fastener on anything.

 

[Bruce Amacker]

Awfully close to 1/4".

 

[Tinner]

.002" under 1/4". Not enough to matter.

 

[ForrestT]

Thank you for the answer. Very interesting to know.

 

[Zrxrunner]

Resurrecting this one because of my find on one of these 6.3 sk sockets. There is o e hose clamp that I come across working on forklifts that no regular metric socket will tighten enough. Guessing this is the one I need to add to the set.

 

[neophyte]

 

[Zrxrunner]

Lol! Just funny how I never really noticed it affect anything other than the hose Clamps. Almost every other application, either a 7mm or 8mm works just fine.

 

[RTM]

Resurrecting this one because of my find on one of these 6.3 sk sockets. There is o e hose clamp that I come across working on forklifts that no regular metric socket will tighten enough. Guessing this is the one I need to add to the set.

Lol! Just funny how I never really noticed it affect anything other than the hose Clamps. Almost every other application, either a 7mm or 8mm works just fine.

Ever wonder if it’s an SAE sized hose clamp? I noticed on my Made in China CAT compressor that the pressure switch fittings are US standard pipe threads, not metric.

 

[jbltwin1]

We had a lot of screw fasteners back in the transition time (77-79) that were 6.3mm on GM cars. We had green 6.3 shafted bolts too. Drove us nuts when the replacement core supports came in as 6.0 and we had 6.3 bolts. Snapped of a few before we figured out you just had to replace ALL the hardware to put a radiator support in!

 

[Zrxrunner]

Ever wonder if it’s an SAE sized hose clamp? I noticed on my Made in China CAT compressor that the pressure switch fittings are US standard pipe threads,

Ever wonder if it’s an SAE sized hose clamp? I noticed on my Made in China CAT compressor that the pressure switch fittings are US standard pipe threads, not metric.

Kinda have to guess on the hyster lifts. Assumed it's sae clamp, but pretty much everything ele on the lift you can just bring a metric socket set, and everything crosses. When the Clamps take SAE socket, metrics won't cross....until now! Lol. Thanks SK!! Just need to make a space in the metric rack for it

 

[2ndGearRubber]

You guys don't need a metric 6.3mm, you need a 1/4 socket.

 

[RTM]

You guys don't need a metric 6.3mm, you need a 1/4 socket.

Shhhh, don’t mess with the mathematically challenged.

 

[Fedwrench]

I know this is a three-year-old thread but when I read 6.3mm SK 1/4 inch socket, the first thing I thought was that the chinafication of SK tools is now complete

 

[four.cycle]

chinafication

^ Is this now part of the English lexicon?

Does Oxford know about this one?

 

[Steve_P]

I bought my first tools in ~1985 from Harbor Freight- mail order. The catalog they'd send you was small, just the basics, 30? pages, more like a typical sales flyer today than an actual catalog. The socket sets came in metal boxes, basically copies of the SK sets. For $35-40 you'd get 1/4, 3/8, 1/2 sets in three boxes in either metric or inch. Each drive set had a ratchet, sockets... The sets were made in Taiwan, and the quality was very good for the time- not the $5 junk sets that was at flea markets. Ratchets weren't the best, but typical round heads for the time.

And now to the point.... the 1/4 drive metric set had 6.3mm sockets in shallow and deep.

Edit- I still have these and use them if I need to take them to someone's house to help out. Having everything in a metal box is great for portability. I've replaced most of the ratchets with slightly better ones.