I installed the bolt by hand using a ratchet, uninstalled it and installed it once more, got about 2″ into the wood at which point the bolt broke. Both times the bolt was being installed into wood and I also pilot drilled the hole in both cases using a 3/16″ drill bit. Is this typical and if so, should lag bolts never be used again once installed?
The bolt in question was a 5/16 x 2+1/2 plated steel lag bolt.
Thanks,
learner
This 654-sq.-ft. ADU combines vaulted ceilings, reclaimed materials, and efficient design, offering a flexible guest suite and home office above a new garage.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
Probably Chinese lag bolts.
They are high in lead content.
Wow! Ya beat me to it. Sounds like typical Chinese made junk. Junk, junk, junk!
Taiwanese according to the box, they are from http://www.hpaulin.com, though I just bought them at HD.Not sure if the Chinese thing was a joke.Just concerns me that a lag bolt would fail on install - guess better on install than post install =). If they are that brittle or prone to failure I would sure hate to use them on something more structural than my lcd tv mount - even that makes me nervous.The bolts that came with the mount were black and the bolts that I used to replace the originals are this shiny plated metal so I was wondering if perhaps I choose the wrong type of metal or if it is just normal for a few to have defects or if they are really only suppose to be installed once. Many possibilities and with no instructions on the box I am left guessing and hoping that the ace contractors here will know the facts.
Taiwan, could be better than Chinese, but probably no difference. Home depot is a poor place for hardware.
"Home depot is a poor place for hardware."He can bet they bought from the cheapest bidder
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
not a joke...
and Tiawan is now the ROC and has been for some time...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
I'm confused ... If Taiwan has been part of mainland China for some time ... why is our 7th fleet making it clear they will keep mainland China's troops off the island? Are you perhaps thinking of Hong Kong? Whether there is a quality difference between "Taiwan" and "China" is a bit of a red herring .... what matters is the reputations of both the guy whose name is on the box, and the place that sold it to you. This is where the parts houses seem to have the box stores beat; they have a bit more reason to care about what they sell. Likewise, I suspect that one of the reasons I've had better experience with Simpson screws, than the generic, is that Simpson has put their name on them. If I didn't know who made them, I couldn't hold them accountable when something goes wrong.
ROC is Republic of China, not the mainland. It is the official govt name for the country. Taiwan is the name of the primary island they inhabit.
Maybe you were thinking of Hong Kong.still makes little difference to this discussion
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I'm confused ... If Taiwan has been part of mainland China for some time
No, he said "ROC" not "PRC"--Rebublic of China vice People's Rebulic of China.
For diplomatic purposes, Taiwan is Republic of Taipei, even if most of the businesses there use ROC on their labeling. Which keeps it much simpler if that company is based in Taipei, the capital city. (In every case, avoid the Nihongo formulation "formosa" except when refering to a blend of oolong tea.)
Oh, and to the topic, a Taiwanese company can buy PRC steel and machine it; or they can buy product from People's Collective Lag Screw Factory #37 and box them as "Product of ROC" for sale in places sensitive to "Made in PRC"Occupational hazard of my occupation not being around (sorry Bubba)
Thanks for un-confusing me :D
the replacement bolts were of inferior quality fro a place to be questioned...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
Why not use the ones that came with? They were rated for the application.I can't recall if this applies to lag screws or just to bolts, but if you look at the hex head of the bolt, on the flat top, you can see from one to five raised markings. These indicate the strength of the bolt. Critical applications should have three or better. A One only is fairly easy to break by comparison. Cars and trucks will have 3-5. For all I know, some uses might get a seven! Five is the hardest I have seen.I would not be surprised if your Chinese HD lag screw is unrated with none of these indicators.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Grade 8 is the highest I have ever used, they are TUFF.
here ya go.
Head Marking
Grade andMaterial
Nominal Size Range(inches)
Mechanical Properties
Proof Load(psi)
Min. Yield Strength(psi)
Min. Tensile Strength(psi)
US Bolts
View ImageNo Markings
Grade 2
Low or medium carbon steel
1/4 thru 3/4
55,000
57,000
74,000
Over 3/4 thru 1-1/2
33,000
36,000
60,000
View Image3 Radial Lines
Grade 5
Medium Carbon Steel, Quenched and Tempered
1/4 thru 1
85,000
92,000
120,000
Over 1 thru 1-1/2
74,000
81,000
105,000
View Image6 Radial Lines
Grade 8
Medium Carbon Alloy Steel, Quenched and Tempered
1/4 thru 1-1/2
120,000
130,000
150,000
Stainless markings vary. Most stainless is non-magnetic
18-8 Stainless
Steel alloy with 17-19% Chromium and 8-13% Nickel
1/4 thru 5/8
40,000 Min. 80,000 – 90,000 Typical
100,000 – 125,000 Typical
3/4 thru 1
40,000 Min. 45,000 – 70,000 Typical
100,000 Typical
Above 1
80,000 – 90,000 Typical
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
New book alert; Eckhart Tolle "A new earth"
A must read.
Edited 5/26/2008 2:13 pm ET by Sphere
There I go.Can you tell how much I do mechanics?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I try to NOT be a good mechanic, grease and woodwork don't mix well.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
New book alert; Eckhart Tolle "A new earth"
A must read.
Exactly right, unrated. I've looked around at quite a few different places for fasteners just seems hard to find good quality stuff to buy.Most recently I've found the best way to do things is to review manufacter catalogs and then find the supplied that carries the items I am interested in. Rather than going to the store and looking to find something that suites my needs.Next time I need lags I won't be buying the unrated ones. I'll also follow the other advice, pilot/clearance/countersink drill for the holes instead of just pilot and I'll lube the threads and increase the size of my pilot. I'll have to take a look more closely at the grk fasteners. I have a box of their M4s I think but I didn't see that they made lag bolts as well.
they are a washer head structural screw to substitute GRKs for lags
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
You've hit on one reason I use, almost exclusively, lag bolt made by (and displayed with) the folks who make Simpson Strong-Tie connectors.
Sure, their bolts are expensive ... and only 1/4" (that I've seen) ... but they are noticeably better than generic lag bolts. They also have better points, and hex washer heads - makes for a better ratchet drive.
It's a hard thing to be persuaded of, but it seems that there's little savings in using cheap hardware.
The GRK 3/16" self drilling laghead screw is tested to do the same a typical 5/16" lag screw will. I happen to think it is slightly better than the Simpson screws
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
I believe the proper pilot for a 5/16 is 1/4, and the clearance hole is 5/16.
You may have heated it enough installing the first time to weaken the cheap steel and twisting it out and then back in may have work hardened to soft spot. I've broke quite a few doing the same, don't feel bad.
I'd bump up the pilot hole, and lube the threads, a candle is in my hammerdrill and impact driver "supplies" boxes now.
edit for sloppy speelling
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
New book alert; Eckhart Tolle "A new earth"
A must read.
Edited 5/26/2008 12:17 pm ET by Sphere
"You may have heated it enough installing the first time to weaken the cheap steel and twisting it out and then back in may have work hardened to soft spot."If you had gotten the thing hot enough put it in and taking it out to affect the strenght then you would not be worried about the bolt breaking. Rather you would be call 911 to put out the fire and then going to the hospital for you burned hand.More like a inclusion of slag get into the middle of the bolt..
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Frenchy told me, it has to be true.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
New book alert; Eckhart Tolle "A new earth"
A must read.
I've had lags break like that even decades ago, when everything was US made. I don't know how you for sure get good lags, unless perhaps you can find some Simpson branded ones.
Most lag bolts are "junk", to be honest about it. I've had countless lags break over the years. Usually they break right where the threads meet the smooth part of the bolt.
The only ones I've seen that are really good are the galvanized ones the power companies use on poles.
Exactly where this one broke.
since you were screwing it into wood, it was a lag screw, not a lag bolt. Right?
Probably cheaper Chinese steel.
I was just using a hole saw this week with a 4" drill and a 1/2" drive mandrel/arbor. when the saw wedge-locked, I snapped the steel arbor. It was a Cheap China knock-off.
so I bought a Makita replacement.
I also have a 5" black bruise on my inner thigh where the drill handle whopped me a good one, for those who are curious
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
with a 4" drill
How many amps does that thing draw?"Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
dunno, but it can smell hot sometimes.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
You missed my humor. You said a 4" drill. I assume you meant a 4" bit. You know, like a 3/8" drill ... never mind."Put your creed in your deed." Emerson
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
Another good lube for lags is bar soap. Load up the threads with soap then drive into pilot hole at slow speed.
liquid dish soap works even more gooder...
easier to apply too...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
I guess soap wouldn't matter indoors for lube, but I've heard that it leads to rust.
Yeah, granny's lye soap is a no-no.
Soap does seem to cause rust, I have a screwlube stick from somewhere, I don't know where I got it. Cardboard tube and pushes out a wax plug like an old time popscicle.
Must last forever, I've had it since I don't know when. Soft wax, like hard pastewax.
And Doud stocked us all up with bees wax cakes that are handy, my wife took one for sewing thread. Used to use that too when I tied flies for fishing, makes the thread stay stuck between wraps.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
New book alert; Eckhart Tolle "A new earth"
A must read.
"Stick Ease" ? I got mine (sounds like the same stuff ) from a glazer buddy of mine. I cut chunks off of it and pack them into old 35mm film tubes or else old prescription bottles. Works great , and is always handy .
They can't get your Goat if you don't tell them where it is hidden.
Just dug it out of the shop.
"Work Site, professional Quality, Tube wax Lubricant" No.WS140
C.R. Laurence Co. Inc.
Glaziers Industrial Construction and Automotive supplies.
Sawing, tapping,drilling, fastening, grinding and sanding.
Now why would one want to sand with wax lube?
Man, that's a mouthfull huh?Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
New book alert; Eckhart Tolle "A new earth"
A must read.
"Akempucky - The Duct Tape of Lubricants"
Edited 5/27/2008 1:07 pm by JohnD1
That would be the sensible name but no the box says lag bolt. The ones that do not screw in AFAIK are called carriage bolts.
I am yet to find a rated lag bolt. I am sure the exist somewhere. After years of twisting off lag bolts, I have learned that the trick is to match the pilot bit with the wood. Like any piece of steel if you bend it enough it will fail. Unlike drywall screws which are hardened and shatter lags are soft. You can feel the bolts spring back a smidgen with each turn of the ratchet when the pilot hole is to tight for the material. Each flex with each turn of the ratchet both in and out takes some of the life out of the bolt. Soft wood, and putting it in only once, application subject to pull out stresses, then use 3/16 pilot. Hard wood, stress in shear, planning on repeated removal might suggest 9/32 pilot.
Good advice. Wouldn't have thought to think about the spring back effect of the softer metal.Thanks,learner
Alright you've convinced me.I bought a box of 50 of the lag bolts but I think I need either a higher grade or a different fastener like the grk or the ledger lok. I'll do some research on those or where to buy the higher grade lag bolts.As much as people rag on HD they do have a pretty good return policy so I'll just take my box of 46 and the one broken piece that isn't in the wall back and say I wasn't satisfied. Not really worth a trip just to return them but I am out there all the time anyway and I figure returning them is going to make the point that they shouldn't necessarily buy the cheapest thing and some people actually are willing to pay for the higher quality materials - that they don't stock.Great discussion, thanks everyone for all the input !!!learner
No doubt that the lag you used (and broke) was of marginal quality. OTOH, I think it was probably a case of the pilot hole not being big enough. The size of the pilot hole is a function of the fastener diameter, but also dependent on what the fastener is being screwed into. Screwing into an oak 2x4 is different than a pine 2x4, OTOH, if the pine is 50 years old, it might likely be much different than a new pine 2x4. If, when you were installing and removing the bolt you had to use much force that would be the clue. I'm sure twisting it in one direction to install, twisting it in the other direction to remove, and then twisting it back didn't help at all either. I'm guessing you used more than 3 fingers on your ratchet as you installed/removed/installed the fastener in question.
My point being that if it takes a lot of force to install a fastener, you need to be aware of the risk breaking it. "A lot" being subjective. You have to adjust the "A lot" adjective to the fastener size and strength. It's just the kind of thing that you get a feel for. Breaking several fasteners helps teach this skill. A slobbering maintenance man might likely be much better adept at this than a PHD graduate. Using a wrench with a long handle can definitely effect the situation too.Knowing how tight to make a nut/bolt pair (without a torque wrench) is the same deal. Using a torque wrench a fair amount teaches this particular skill. Stripping and breaking some helps too.
I gave up on lags a couple years ago. I like LedgerLok screws now. The engineering info is right on the box and they're the equivalent of 1/2" lag screws. No pre-drilling. Just zip them in with a low RPM drill and you're done. Great product.
Thanks, I'll have a look at these.
I second that! Here's the spec's on those. Their TimberLok's are also a cool product.
http://www.fastenmaster.com/Files/FastenMasterProductFiles/9/MerchandisingInfo/LedgerLok%20SS.pdf
I like LedgerLok screws as well, but one county here will not let us use them. They say that the screws are not rated according to their resistance to corrosion. That is maybe technically true, but then they will accept no-name lags of questionable quality from who knows where.
I just posted a new thread about this same county who is requiring drain tile on crawlspaces, which I think is wrong.
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Good advice from Sphere about lubing with bees' wax (I often use construction adhesive or caulk). Maybe need slightly bigger pilot holes. Like you say--better for it to fail now than when your kid is playing on it!
since this is a TV mount, the kid would be playing under it not on it, right?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Somehow I missed that it was a TV mount--remember some worry about kid and thought it was some sort of play thing (like an outdoor treehouse, slide, swingset deal).