The Home Machinist!

Is a grade 8, alloy steel socket head cap screw from Brighton's Best as good as one from Holochrome? There is a big difference in price.

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Mr Ron, Almost as smart as the average bear.

I can't say, but it might depend on what you are using them for.

If my life depended on it, I'd pay extra for the known good ones. If it were for hanging pictures, the cheap ones would be fine.

Can you get a sample and check it out?

I've seen socket head screws that were made out of butter (actually, that would be an insult to Land '0 Lakes).

Steve

I think our purchasing department insisted on "certification documents" with all screws above grade two. Don't remember what the docs looked like, but you might scare a vendor of counterfeit parts by asking.

Dave J.

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Every day I ask myself, "What's the most fun thing to do today."
9x48 BP clone, 12x36 lathe, TIG, MIG, Gas, 3 in 1 sheetmetal.

FWIW I have used thousands of G8 Brighton's with nary a problem.

Brighton-Best screws are imports. good for non critical applications. There cap screws are OK. I would not use their set screws
Holochrome screws are top quality domestic made screws.
Holochrome set screws are clearly stronger then any imports that I have ever used.
I will not use imported set screws

Thanks all. I'm not building a space ship, so Brighton Best will serve my purpose. I thin they are made in Taiwan, not China.

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Mr Ron, Almost as smart as the average bear.

I bought some grade 8 bolts at lowes when building my shop press and they broke when tightening them. They were only 3/8" dia but it shouldn't have happened.

There are folks who will mark bolts any way you want. Just because the bolt is marked grade 8 does not mean that is is actually grade 8. It is becoming progressively harder to find quality hardware in small amounts. Quality fasteners are still available from distributors in package amounts

Even years ago when American manufacturing was going down the tubes, I remember something. It has to do with no $10k toilets or whatever. It was gov't outsourced bidding or whatever for Lowest price. There were failures and death due to fasteners that were no longer to mil spec. Many tons of these were sold " as is", scrap hdwe, no warranty implied. Virtually all better than hardware grade yet not exactly as marked. I understand there are failures on ckt bds which are introduced into our defence equip and they were bought from guess where.? Capscrew bolts are what we see. Verify before trust when it's important.

Huge Difference fellows !

First, HoloKrome(HK), Unbrako,Cam Carr, and Allen, are American companies that must abide
by the 1962 ANSI Standards.
These standards say that ALL Socket Head Cap Screws ( SHCS) and socket head set screws ( SHSS)
must be made from 176,000 PSI Steel OR BETTER. FYI< The best is Unbrako , and they will not use anything under 180,000 PSI ( 185 K for under 1/2" diameter !)
Now, Grade 8 bolts are only 146,000 PSI just for a comparison.

Foriegn manufacturers have no such standards, and in fact they make about 5 of 6 varieties of SHCS.
Now some will follow the German Metric Standard called "DIN"
DIN has several grades , like 12.9 and 10.9 and 8.9 and 5.9 etcetra.
Now 12.9 is almost the same level as American 1962 ANSI standards ( 176K)
and 10.9 is close to our Grade 8 level
A DIN 8, is NOT a Grade 8 comparison !
And anything else will just explode under load as I am sure we have all seen !

So when you buy a box of Socket Screws, either Cap or Set , you better know the standard used.
Buy the above American suppliers and you get repeatable use without failure
In simple terms, there are no guarantee with foriegn stock...unless it says DIN 12.9, even on their American threads !

Rich

As SPRO said, the government learned the above in the 1980's When they built the Bradley Fighting Vehicles and had to recall and replace all the Cap Screws, because they were foriegn made.....and failing

A friend of mine is a mechanic for a tour bus company. They take safety very seriously and replace all wheel studs everytime a wheel is off. About 15 years ago, they had a wheel fly off on the highway despite this policy. It turns out that the studs they purchased were counterfeit and nowhere near the specified grade.

I would think that wheel studs torqued to their specified foot pound spec should be reusable.
I do not claim expert knowledge on the subject, can someone confirm or disprove this?
Are these parts stressed to their elastic limit