Broken Lag Bolts

I am moving my DC from the floor to hanging on the wall. When I was installing the brackets 2 of the lag bolts just snapped in two, right where the threads start. The last 2, of course. They are 1/4-4" bolts and I drilled a pilot hole just about the size of the shaft (not counting the threads). So, now I have to move the whole operation either higher or lower, what a pain.

I have never seen a lag bolt snap like that? I feel like maybe I shouldn't trust these bolts with a 200lb chunk of metal over my head. Anyone have any ideas why this happened and maybe what kind of bolts I need to use?

Thanks,

Attachment 387143

Going into what, pine studs? Were you having to crank pretty hard? (Almost looks like it from the head but hard to tell from a picture.) A slightly larger hole and some wax rubbed into the threads might eliminate the need for a lot of force from friction.

I don't use 1/4" much here on the farm, I prefer 5/16 or 3/8" for almost everything, sometimes larger. They don't make hardware like they used to so I prefer larger.

JKJ

Quote:

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Originally Posted by David Justice

I am moving my DC from the floor to hanging on the wall. When I was installing the brackets 2 of the lag bolts just snapped in two, right where the threads start. The last 2, of course. They are 1/4-4" bolts and I drilled a pilot hole just about the size of the shaft (not counting the threads). So, now I have to move the whole operation either higher or lower, what a pain.

I have never seen a lag bolt snap like that? I feel like maybe I shouldn't trust these bolts with a 200lb chunk of metal over my head. Anyone have any ideas why this happened and maybe what kind of bolts I need to use?

Thanks,

Attachment 387143

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http://www.spax.us/en/power-lags.html#.WxX51kgvztQ

I've never wrung one of these in two.

Double, triple ditto marks on Tom's reply. Box store lags bolts can't withstand the rotational force to drive them home even with a pilot hole and waxing the the lag. I switched to Spax and I have never snapped one of them. I use their #6.8.and 10 screws too now.

Thanks everyone. Spax lag bolts it is! I'll be picking some up today.

I prefer the GRK RSS over the Spax, partly because I hate the store that sells Spax here, but also because I think they are better. Either is better than a cheap lag bolt though.

https://www.grkfasteners.com/tech-data/specs/rss

That is a typical lag bolt failure and it can occur even after you have completed your assembly. Most lag bolts sold today are of lesser quality and should not be depended upon for wight bearing. I use the better grade Timber lok screws now instead of lag bolts.
Attachment 387248
These are like grade five bolts for wood.

Quote:

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Originally Posted by Steve Rozmiarek

I prefer the GRK RSS over the Spax, partly because I hate the store that sells Spax here, but also because I think they are better. Either is better than a cheap lag bolt though.

https://www.grkfasteners.com/tech-data/specs/rss

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Another vote for GRK RSS fasteners. HD sells them.

I'm also a big fan of timber locks. They are rated as strong as a 1/2" lag bolt. I drove hundreds of them when I built a retaining wall out of 6*6 pt wood without one issue . You can get timber locks at lowes

I already installed the 3 5/16 Spax lag screws per bracket. I'm 220lbs and can hang from them and they don't move at all. My DC motor is about 150lbs, so I think I'm probably good. I'm also going to have a 2x4 stud propped under it to help. Probably overkill, but better than it falling on my head.

I looked at the technical specs and the Timber lock and Spax are about the same as far as weight bearing.

I use any of the goods ones mentioned so far, with the only preference going to the nearest seller when I need some.