Grade 5 vs Grade 8 bolts... the hot skinny!

[Jay4200]

Informative but not complete. You are at a big box store and choose grade 8 bolts, what nuts and washers do you get?
The nuts and washers should also be grade 8. Unless marked you will be picking up grade 2 or 5 hardware.
What if you are replacing a lower grade bolt with a higher grade, no nut to screw the bolt into, the frame is tapped?
A] You drill out the tap and use the same grade nuts.
B] You use a longer bolt to thread deeper into the blind pocket.

Washers are stamped or CUT from sheet metal. The stamping causes a slight CROWN in the washer, take advantage of the crown by placing the flat side away from the bolt head or nut.

I have found that the chine's nuts and washers much too soft for the bolts.

I don't believe that bolt grade matters. The failure mode is in the bolt (shaft). Type of nut or threaded holes are irrelevant in terms of fastener failure.

I need to pick up some grade 2 bolts - where do I find them??

JayC

 

[picker77]

Picker, Race Brothers is another great place to buy grade 5 and grade 8 nuts and bolts by the pound, and also bulk chain, their prices on chain are cheaper than TSC. in all grades. I dont know if you have a Race Brothers store out there in OK land, but we have several in the area here.
James K0UA

No Race Brothers stores around here, just several Tractor Supply and Atkinson's farm stores, plus the usual three dozen big box places. When we lived in northern Wyoming we bought stuff like this at 'Linton's Big R' in Powell, WY, or at the local NAPA store, which also sold fasteners by the pound. I really liked that Big R store, you could have dropped five Tractor Supply stores in that place. There are plenty of industrial fastener suppliers near where I live now, and some of them will sell retail in boxes of 100, bulk, or whatever--usually pretty reasonable. That's where I go if I need a bunch of a particular item.

I just made an interesting price comparison between the local Tractor Supply and a typical large online nut/bolt retailer (www.boltdepot.com): For what I bought yesterday, TSC's price was $13.67 including sales tax. Bolt Depot was $24.34 plus $11 shipping. Such a deal... :laughing: It certainly pays to shop around.

JayC: Tractor Supply carries 2, 5, and 8. Pretty good selection, too.

 

[clemsonfor]

Actually, the difference in strength isn't as drastic as I expected it would be. However, I like the bonus of the nice finish and gold-anodized color of Grade 8 hardware. Could be my imagination, but they also seem to hold up without corrosion much longer than the white-finished Grade 5 stuff.

I used to go to Lowe's or Ace Hardware for nuts and bolts and such, but then Lowe's started packaging fasteners in cute little individual onesies-twosies plastic packs, and ACE even prices them per each. In either case the total price can be a shock if you need a dozen or more. However, I found out a while back that Tractor Supply sells their fasteners by the pound, and simply charge a different price per pound for each grade. Since I use Grade 8 for almost everything, about every time I'm in there for something I stop by the fastener aisle and load up with another two or three pounds in common lengths and sizes. By so doing I've built up a decent inventory of Grade 8 fasteners in my shop without going broke doing it, and they have come in very handy.

My local carquest here sells buy the lb. If you buy them from the owner it is alot cheaper than one of his employees who seem to make up prices. i paid $12 for like 6 bolts n nuts only 2 were grd8 sets. He will sell you stuff cheaper than TSC i buy all my bolts from him as its much cheaper than Lowes. Lowes is like several dollars for a 3/8 grd 8 bolt several inches long.

I bought 5 plow bolts from shannon at carquest grd 5 and he charged me $2.50 at TSC i bought 5 more for almost a $1 or so more!! i have learned buy bolts from carquest, and its only 10 mins to carquest and almost 30 mins to lowes or TSC.

 

[clemsonfor]

I don't believe that bolt grade matters. The failure mode is in the bolt (shaft). Type of nut or threaded holes are irrelevant in terms of fastener failure.

I need to pick up some grade 2 bolts - where do I find them??

JayC

type of nut is important if its under tension a softer grd 2 or 5 nut will just have the threads pulled out of it once it gets near the breaking limit of the nut!

 

[picker77]

Please don't think I'm shilling for TSC, they just happen to be 4 miles from me so are handy when I'm in the middle of a project. TSC ticked me off mightily when they dumped all their decent tools and such and went to all Chinese stuff. But the dingleberries at Lowe's will just give you a thousand-yard stare if you need anything farm related, like a Cat 1 hitch part, a hydraulic hose fitting, or a PTO part. I could save a few bucks by driving 20 miles into Oklahoma City to a real industrial supplier, but at $2.70 a gallon for diesel that doesn't always make economic sense these days.

 

[psj12]

The Army requires grade 8 bolts (and nuts) on all its' vehicles. Even they got taken a few years back when they discovered many failures in the field that we traced back to conterfiet bolts. Seems they bought millions of these fasteners and had to replace them d all. It seems the suppliers had found a "good" deal from where else, China!

The suppliers had to get rid of these bolts somewhere. Watch wat you buy.

 

[ShenandoahJoe]

Every application for a washer that I can think of, right off, softer steel is good. When would you want washers to be grade-8 hard?

 

[Soundguy]

yep our local hardware store started pricing by each recently.

for regular 2, 5 or 8 stuff in 1/4 to 5/8 I hit tsc and buy in bulk.. hard to beat those prices.

soundguy

Actually, the difference in strength isn't as drastic as I expected it would be. However, I like the bonus of the nice finish and gold-anodized color of Grade 8 hardware. Could be my imagination, but they also seem to hold up without corrosion much longer than the white-finished Grade 5 stuff.

I used to go to Lowe's or Ace Hardware for nuts and bolts and such, but then Lowe's started packaging fasteners in cute little individual onesies-twosies plastic packs, and ACE even prices them per each. In either case the total price can be a shock if you need a dozen or more. However, I found out a while back that Tractor Supply sells their fasteners by the pound, and simply charge a different price per pound for each grade. Since I use Grade 8 for almost everything, about every time I'm in there for something I stop by the fastener aisle and load up with another two or three pounds in common lengths and sizes. By so doing I've built up a decent inventory of Grade 8 fasteners in my shop without going broke doing it, and they have come in very handy.

 

[JIGBUILDER]

Just a point on grade selection for the job. I spent nearly 40 years as a journeyman aircraft tool builder/jigbuilder, so I have some bad experiences with removing the wrong grade broken SAE fasteners/MIL spec bolts from a blind hole.

Generally bigger is better if the hole is a thru hole with a nut and bolts. If the bolt breakers its usually easy to gets both ends out. If the hole is drilled and tapped and is a blind hole, and a grade #8 bolts is used instead of a #5 or #2 and it breaks off for whatever reason. Your in trouble. With a softer bolt like a 2 or 5, a hole can be drilled down through the broken bolt and removed with a easy out. Some grade 8 bolts may be drilled into with a cobalt or HS drill. Some grade 8 bolts may have more carbon than others. Get the bolt to hot will drilling can cause the bolt to harden even more. Then it requires a expensive carbide drill to get a hole deep enough for a easy out. This is a worse case scenario. And yes I agree build it stouter but don't shoot youself in the foot with the wrong fasteners application.

Anyone remember the great fastener debacle in the late '70s/early '80s (I think). Inferior bolts were imported into the US. I believe there was a building collapse and was determined low grade inferior/cheap bolts were the cause of the collapse.

I only use a grade 8 if its a requirement.

 

[Skyco]

However, I found out a while back that Tractor Supply sells their fasteners by the pound, and simply charge a different price per pound for each grade.

At one time TSC sold metric fasteners by the pound too...it astounded me when they discontinued that line considering so many things have metric fasteners now, including a lot of tractors...