Just for the heck of it, a little discussion of why it is what it is... and a little of my easily debatable logic.
As for the lock washers, I'm aware of the studies that say they're useless. However, when you want information, it's sometimes easiest to follow the money! As far as I know, all the automotive manufacturers still use the old lock washer on almost every threaded fastener. Just pick the brand whose engineering group instills the most confidence and take a look. One thing I learned in many years as an automotive supplier is that no one, including NASA, has the engineering might of the combined auto companies. There's just too many of them! Even more obvious, was the fact that no one has even a remotely comparable cost reduction effort.
GM, Ford, and Chrysler sold 7 million vehicles last year. That doesn't include Toyota Honda, etc. Assuming that each vehicle had 500 lock washers, (pretty conservative guess, I think) that amounts to 3.5 BILLION lock washers. Assuming they buy them at 5 washers per penny, that totals 7 million bucks! Then assume it takes about 1/2 second to install the washer; that totals about 486,000 man hours. At a loaded cost of about $100 per man hour (that's way low), that comes to about 48.6 million bucks to install the washers. Total it up, and convince me that the auto guys would spend that kind of coin for something that didn't work or add value. I don't know whether or not they work. They seem to think so. So I'll give you a lock washer to use if you want. BTW, someone check my arithmetic. This late in the evening, the function of my brain is as debatable as the function of that lock washer.
Next topic is the advantages/disadvantages of the nylon locking nut. We use lots of those. For instance we use them on every fastener on our bolt on thumb. In the case of the Piranha, I find that a couple of turns of the nut with a trusty adjustable wrench lets me remove it the rest of the way by hand. I usually don't have to hold the bolt with a wrench. With a Nylock, you screw it all the way off or on, with two wrenches. I'm pretty lazy when it comes to installing attachments and that two wrench thing is too much work for me. Of course most folks tell me that they never take it off.
Bolt inside or outside? I recommend from the outside. If you happen to be working in rock for instance, everything that makes it into the bucket is loose. It's also unlikely that it's a 10,000 pound boulder. The big rock you just hit with the outside of the bucket might well be anchored pretty solidly. Again, we're all big boys. Put it in whichever direction makes you most comfortable, but that's my logic.
Lock washer useless? As I said, I don't know about that. The washer on the outside of the bucket on the other hand... It's there for a rather unusual reason. People expect a washer! It really has no functional purpose other than preventing your wrench from scratching the outside if the bucket when you tighten the bolt. If we don't supply the washer, we'll get calls... The bolt takes little load. The way the Piranha fits onto the edge absorbs the twisting and digging forces. The bolt pretty much just keeps the PTB from falling off as you back drag.
I hope everyone has a great weekend and gets to work in a little tractor time.
Harry
BXpanded
