| | | quote | Originally posted by FTF Engineering:
Yeah, I made that mistake once as well. I was replacing some hardware and figured "If stainless was good on one end, then stainless on both sides would be even better, right?"
Wrong.  My experience was very similar to yours and after a little investigation, I found that it's actually quite common. Consider yourself either lucky or good that it hasn't happened to you in the past!
There's lots of info about galling online, but since we were talking about Fastenal... Here's a doc from them that warns about the risk of galling. "Stainless steel fasteners are particularly susceptible to thread galling".
http://www.fastenal.com/con...le%20-%20Galling.pdf
Not to say that it can't be done, but it usually takes some special precautions and lubricants, etc.
|
|
That's very interesting. But it seems that they're talking about galling as being something that usually occurs AFTER the nut is tightened down, making it unable to remove it. I never got the nut down to the mating surface before it LOCKED UP.
Things to note in that article:
- "Galling, often referred to as a cold-welding process, can occur when the surfaces of male and female threads are placed under heavy pressure." - There was no "heavy pressure". I didn't even get them to tighten down.
- "Use coarse threads with a 2A-2B fit instead of fine threads. Coarse threads have a larger thread allowance and are more tolerant to abuse during handling." - I was using course threads.
- "Heat contributes significantly to thread galling. Fastener installation alone generates friction and therefore heat. An increase in speed during installation increases the friction (heat) between the threads. Lowering the wrench speed during installation and removal can help avoid galling." - I was using a ratchet; there was no "speed" involved.
- "A smoother surface texture will lead to less frictional resistance. Rolled threads usually offer smoother surfaces than cut threads. As previously mentioned, friction increases the possibility of galling." - I'm sure all the chinese bolts we're getting are cut threads.
I still contend it was cheap chinese-made bolts that were the CAUSE of the problem. I DO know that the aircraft industry quit using chinese made fasteners DECADES ago because they were not the grade marked on them. Just one more reason to buy MADE IN U.S.A. products whenever you can.
~ Paul
aka "Tha Driver"
Custom Fiberglass PartsChina scorecard:
1) Bolts not up to grade. The *aircraft* industry had several failures because they were marked a higher grade than they were. They no longer use imported bolts.
2) Poison pet food.
3) Poison pet food - again.
4) Tires that blow out.
5) Poison toothpaste. Contains the same toxic that's found in anti-freeze.
6) More poison toothpaste. Import of toothpaste was banned from china so they combined it with toothbrushes so that it could be imported as "toothbrushes", to get rid of the poison toothpaste!
7) Toys made of lead. Imported by Mattel.
8) Toys with lead paint & small magnets that can kill children if swallowed. Imported by Fisher Price.
9) Poison pet food - the third time.
10) Poison children's paint sets - sold at Toys R Us.
11) Bugs in candy bars.
12) More (nearly a million recalled) Mattel toys with lead paint.
13) Flip-Flops at wallmart that cause a rash.
14) 1 million baby cribs recalled after 3 children die.
15) About 1.5 million Thomas the tank engine toys.
16) "Play Yards" with strings that strangle children.
17) Happy Giddy Garden toys that - you guessed it - contain lead.
18) Purple haloween pails from Dollar Stores that contain lead.
19) Disney Winnie the Pooh dolls that contain lead.
20) Bead kits that contain lead.
21) 500,000 KB toys wooden blocks that contain lead.
22) Baby Einstien toys that contain lead.
23) "Discover & Play" blocks that contain lead.
24) 1.5 MILLION Cub Scouts "Totem" badges that contain lead.
25) Levels that are NOT LEVEL! Try building a house with that!!!
26) Recall of certain children's items due to a lead exposure risk or entrapment/suffocation/choking hazard. The products include Halloween-themed baskets, children's jewelry, shaving paint brushes, pencil pouches, Boppy pillow slipcovers, flashing pacifiers, and storage racks with canvas totes.
27) COUNTERFEIT smoke detectors! Wonder how many folks have BURNED TO DEATH because of them?
28) You can add chain block that give while lifting a Fiero too. Lucky i wasn't under. Capacity was 2 tons, guy at the store told me that it wasn't meant to lift car. Two tons of car or two tons of S--- what's the difference I answered him. Thing was brand new. - Robert 2 on PFF
29) Toxic lead replaced by even more toxic cadmium in children's toys, trinkets.
30) I needed some lug nuts for mag wheels & couldn't find any that fit. we started checking the sizes & the lug bolts with the SAME PART # in the SAME BOX (made by Dorman in china) had sleeves that were 17.34 MM, 17.24 MM, & 17.18 MM!
31) Children's car seats made with CLORIENE & LEAD.
32) Arsenic in Chinese apple juice.
33) My neice had a problem with her taillights blowing all the time. Took it to the dealership. Know what they told her? "Yeah it's those chinese bulbs - just buy a box of them & keep them in your glovebox". WTF? Why not just buy QUALITY bulbs & quit buying china CRAP???
**) Hell there's so many on the news every night I can't write them down fast enough! FAR more than I've listed here.
I don't know how long it's going to take for everyone to realize that ALL the CRAP we're getting from china is COSTING US MORE IN LOST PRODUCTION TIME THAN THE LOW PRICES ARE SAVING US!!!! AND you're supporting a COMMUNIST REGIME that has the world's WORST human rights record & is BUILDING THEIR WAR MACHINE with OUR MONEY! AND you're killing OUR ECONOMY when you don't buy QUALITY made in the U.S. products.
Com'on everybody - WAKE UP!
Made in China: NOT gonna' buy ya'.
***
Comment from "SCCA Fiero": What's so bad about China? The current dictator is responsible for more deaths than Hitler and Stalin... combined! I guess genocide is cool. But at least they don't censor the internet, and China has freedom of the press... err, wait a minute. I might have my facts mixed up. But I'm almost positive China is not a Communist country, and China has excellent retirement and worker's comp. I'm just glad U.S. jobs are not going to China and the US does not owe China billions of dollars.
The US is going down the toilet and nobody cares because they can buy cheap crap that costs 1/2 of a U.S. made equivalent, but lasts 1/5 as long.
