Broken Screw

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PeteH
Posts: 1065
Joined: Mon Jun 11, 2007 10:49 pm
Location: Tidewater Virginia, USA

Re: Broken Screw

Post by PeteH »

Lew -- THANKS !! A good trick. (As I sit here slapping my forehead, muttering "why didn't I think of that?")
Pete in NJ
pete
Posts: 2518
Joined: Tue Feb 10, 2009 6:04 am

Re: Broken Screw

Post by pete »

I'm certainly not China bashing, I'm simply repeating what I've experienced in industry. Mining has shall we say some hired guns in their purchasing departments that always try and pinch the pennies in one way or another. But at any mine I've ever worked at, you don't and won't ever see anything other than North American or possibly European built grade 8 minimum bolts or screws. It's also not unusual to see bolt bins that hold enough they could easily cost $30,000 or far more just for the contents. I've yet to ever get a fully honest or detailed answer for exactly why, so I'll let you jump to your own conclusions. But I've also seen some very expensive repairs needed just from loose or missing high quality fastners. The same goes for any lifting equipment also, Straps, Slings, Shackles etc are a pretty large and ongoing expense, I've never ever even seen any of it that was manufactured in China. Any that I've ever used was always North American built or manufactured. Food for thought, and maybe something to keep in mind for anything you value or need to trust. Most of the higher quality heavy cable or lifting equipment I've seen lately comes with a tag or label stating it's exact country of origin. There are some things in life where trying to save a few bucks can leave a huge or PITA expensive mark.

Pete
Mr Ron
Posts: 2126
Joined: Tue Dec 22, 2009 12:36 pm
Location: Vancleave, Mississippi

Re: Broken Screw

Post by Mr Ron »

I always buy screws by the box, at least up to the 1/4" size. Maybe I might use just a few at any one time, but a few years later, the price will go up and those screws you bought 5 years ago will save you money in the long run. If I am using screws that require high shear strength, I go with Mil-Spec hardware; (Holochrome for example instead of Brightons)
Mr.Ron from South Mississippi
Joe Gwinn
Posts: 9
Joined: Wed Jan 31, 2007 9:27 am
Location: Boston, MA area

Re: Broken Screw

Post by Joe Gwinn »

seal killer wrote:I was using an arbor mounted slitting saw taking 0.050" DOC on a piece of bronze 932. All went well for about the first three inches along the six inch cut. The M8-1.25x12mm screw holding the saw in the arbor broke. McMaster-Carr (my usual source for stuff) doesn't carry them. Bolt Depot does. I might have to buy a box to get one, though.
McMaster does carry such bolts: http://www.mcmaster.com/#91294A280.
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