Square Bolts?

 
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Scottscoaled
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Post by Scottscoaled » Mon. Jan. 06, 2014 4:09 pm

:rofl: :wtf: :gee:

 
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stoker-man
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Post by stoker-man » Mon. Jan. 06, 2014 4:37 pm

I really don't know why they used square bolts through the years. Maybe so the user could use a Crescent wrench on them, or was it traditional in the 1920's when they first came out and then they never changed? Or were the square bolts the only ones made to grade 8 when they came out?

I think there is a good 3/4" length of threads in the gooseneck and if never seize wasn't used, they could really seize up if left in an unheated boiler. You needed all the strength you could get in a bolt. I've not seen too much trouble with these unless the pot was left in dampness for many years.

 
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Post by LouSee » Tue. Jan. 07, 2014 4:16 am

12 points don't work to well for square, get 8 points. Sears (still) has a pile of them. anti-seize them an a crescent wrench would be fine. Mine are hex now.

There is plenty of hardware in all manner of heads, institutional inertia and/or the 8000 left in inventory perhaps are bigger reasons if new stoves come with square drive heads.

And it's about 125 turns to get the pot nicely setup - just did it a month ago when the pot auger snapped :-( . The handle definitely helps... :-)


 
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Post by blrman07 » Tue. Jan. 07, 2014 7:34 am

Quick price check.

5/16 x 1 1/2" square head bolt = $.20 with nut
5/16 x 1 1/2" hex head bolt = $.45 with nut

Mystery solved on why manufacturers use square head bolts and nuts.

Rev. Larry

 
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Post by Pacowy » Tue. Jan. 07, 2014 8:39 am

That may be how it looks now, but if the selection of those bolts dates from the olden days, there likely was a German Engineering study underlying the design and material specifications. There are lifetime old-school EFM pros who still are trying to figure out why some things were done a particular way, but they won't change them because they know what went into the planning.

Mike

 
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Post by blrman07 » Tue. Jan. 07, 2014 8:46 am

Ok now you got me looking. This is one of those things that won't affect the way of life as we know it but it might win you a bet sometime. The following was quoted from this link......

http://www.practicalmachinist.com/vb/antique-mach ... us-113448/

03-06-2006, 01:04 AM #3 J Gull
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I did some more looking and found this @ http://www.usenews2.org/group/rec.cr...le-545754.html Which says this
"Interesting question. Since I was headed to the library last night, I thought I'd see what I could turn up. From a fastener book from about 1950, I found out that cold-heading machines were around in the 1840s, hex nuts were being punched out of flat stock in the 1880s, screw-making machines(not automated) were around in the mid-1800's and they were rolling threads in the 1880s. No sign of a date for hex head introduction, it was probably wider spread after the Bessemer process made cheap(and uniform) mild steel available. Hand-forged wrought iron nuts and bolts were probably easier to make with square heads. I saw no signs of hex head bolts being milled, they weren't made that way in quantity as far as I can see. Upsetting and forging in a die are lots faster and cost lots less. One short article did mention that larger hex nut stock was planed from square stock before machining instead of starting from drawn or rolled hex stock, for those nuts that weren't punched from flat stock.

Stan"

Rev. Larry
New Beginning Church
Ashland Pa.


 
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Post by franco b » Tue. Jan. 07, 2014 9:08 am

Square head nuts and bolts were far better for use with the open ended wrenches of the day. Too easy to round off a hex head.

 
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stoker-man
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Post by stoker-man » Tue. Jan. 07, 2014 6:06 pm

True, franco. With efm, the square bolt was traditional. They never cut any corners to save money. An extra dollar for bolts wouldn't make a difference in a $9000+ unit.

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