Always double check hardware

[kennertree]

Today i was lowering some pine logs using a block and sling. The spar was 50 feet high or so when i rigged the first chunk to be lowered. I made sure the block was secured to the sling on the first chunk. Several chunks later, I was on the last one. I made sure the ground man was ready and started the back cut on the last log. After he lowered it, i looked at the block and the bolt had worked its way loose. The sling was still attatched to the block but only by luck. Lesson learned..............check your rigging every cycle. Double check it if you have to. This could have been a pretty bad accident. If that block would have came out of the sling it could slingshot that thing at warp speed and hit a groundman or the chunk could have rolled into the pool we were working beside. You will see how lucky i was when you see the pic. Be safe guys, always check twice before ya cut.

 

[Redbull]

Wow!!Thats the same block I use. Thanks for the reminder. Glad everyone/everything is ok.

 

[xtremetrees]

hooyaa!

 

[PTS]

We use those too. Thanks for the heads up. I will share with the guys!

 

[Matt Follett]

Wow

I don't think I ever posted about it... but exactly the same thing happened to me... same block! Scared me silly when I realized, had a piece on, guys lowering down, I looked at the block, and it was spun open, bent and hanging kind of sideways!

yep, check, check, and re check.


Matt

 

[pantheraba]

.

I wouldn't a thunk it...thanks for the heads up.

 

[Sprig]

Yikes!! Glad ta hear nobody squished, whew! I am wondering if it is maybe prudent to either peen the thread on the nut end or drill a small hole and intall a cotter-pin? Might want to look into it as this it is only a matter of time before someone does get injured. I think I'd be talking to the manufacturer real quick too, even suggest something like a nylon lock-nut. Scary.

 

[Ancient One]

Changes are in Order!!

Loctite!!!!!

From my aircraft experience, I would say a good prefilt check of all the equipment is a must for climbers. I would send the photo to the maker and the seller of the block, this is a deathtrap waiting to happen. A huge liabilty isssue, the lawers would jump on an accident resulting from this type of defect. Looks like the sheave friction is unscrewing the bolt.

A question from this non-climber: Is this block rated for overhead use, that is, lifting or suspending loads with personnel underneath???? Looks sort of wimpy as viewed with my machinery rigging experience. I would not bet the life of a groundy on this block.

 

[skwerl]

I have the same block and I am extremely doubtful that the bolt backed out on it's own. Rather I suspect that it never got threaded into the nut when rigged and the user was simply spinning the bolt in place instead of threading it together. Mine has gotten old and sticky so I have to be very aware when screwing it together. The bolt can catch on the pulley and feel like it's screwing in, but it's just pressing against the other side plate and pushing them apart. It may be inconvenient, but I can handle it. And the block was $40 cheaper than the fancy CMI block and has a higher load rating (when it's screwed together properly).

And everyone PLEASE IGNORE THE LOCTITE SUGGESTION! You will ruin your block and make it impossible to open and close by hand.

 

[Tom Dunlap]

Blocks are either rigged right or hopelessly wrong...Clifford Ashley said something similar about knots

This is interesting. In just these few posts on this thread three people say that they've had problems with this block. Why use them? Is it worth any amount of money not to have positive locking pins?

The hardware that's in our climbing systems has to have automatic, positive locks. Also, the specs include a huge safety margin. Keep things consistent and use better gear for rigging.

If threads get sticky the best thing to do is clean them first with solvent and a toothbrush. Then get a tap and die to chase the threads. If that doesn't make thing nice and smooth again, cut the block into little pieces and put it into recycling.

Ever heard the saying 'Penny wise and pound foolish" ? The pounds that we work with aren't currency, their big logs that can come down and kill people. Don't save pennies!

 

[Ancient One]

So, from the above post, are you guys screwing the bolt in and out, using the block as a snatch block of sorts?? No wonder the thing is backing out.

Sorry about the locktite answer, but if indeed the block is used as a snatch block, with no positive locking for the screw, then you are seting up an accident. Ol' Murphy has no forgiveness.

Again, I am not a climber, just offering my one cents worth in trying to prevent accidents. I think you climbers need all the good luck available!!

 

[kennertree]

Yes, it was 100% operator error. On the first chunk i rigged it was screwed in. After that, i never checked it. It should have been checked after every block was lowered. I lowered atleast 10 chunks so in the process of moving the sling down the tree to lower more blocks it came undone. i was using a loopie sling so each time i would undo the loopie so the loopie might have been catching on the bolt each time it passed through the bight and worked it loose. I'm getting a new block this week and im going to make sure its a locking block and im not going with screw type blocks anymore. Anyone using these type of blocks always make sure they are tight. I hope by passing this on it will prevent an accident. Everyone be careful and remember that anything can go wrong even when you do everything right.

 

[RedlineIt]

Hmmm,

Speaking of rotational forces, and looking carefully at the photo kennertree provided, would anyone else say that the lower pulley on this block has NOT been rotating for some length of time?

To me it looks unevenly worn toward the top and the bottom, as if rope has been running over instead of with the pulley.

Clearly, it would not have contributed to the upper sheive failure, but the unit looks a bit skanked to me


RedlineIt

 

[clearance]

Looks like some big force was on that block to bend it like that. Another question is, if you are lowering logs out of the tree you are in, how do you know the tree (spar) is o.k.? Is it load rated?, spars used in logging have lots of guywires and no one is in the bight when stress is on them. Scary stuff, I like to hammer it down, hack it maybe but safe it is. Think about it.

 

[Redbull]

Looks like some big force was on that block to bend it like that. Another question is, if you are lowering logs out of the tree you are in, how do you know the tree (spar) is o.k.? Is it load rated?, spars used in logging have lots of guywires and no one is in the bight when stress is on them. Scary stuff, I like to hammer it down, hack it maybe but safe it is. Think about it.

You do a hazard assesment on the tree before you climb it anyway. If rigging is involved, this includes sounding out the spar and drilling if necessary. During residential work, bombing is rarely an option. A good way to upsell a removal is by offering a zero impact removal, which means rigging off the spar.

 

[Redbull]

Hmmm,

Speaking of rotational forces, and looking carefully at the photo kennertree provided, would anyone else say that the lower pulley on this block has NOT been rotating for some length of time?

To me it looks unevenly worn toward the top and the bottom, as if rope has been running over instead of with the pulley.

Clearly, it would not have contributed to the upper sheive failure, but the unit looks a bit skanked to me


RedlineIt

I have the same pulley and was looking at it last night. I was trying to rotate the lower sheave by hand and it was difficult. Upon further inspection, I found one of the cheek plates was bent. This pulley just got demoted to a redirect.

 

[kennertree]

I believe it is the lighting and camera flash that makes it look worn unevenly.

Dan

Yep, the block is fairly new.

 

[Redbull]

I've only used mine three times and don't remember dropping anything too large on it, but it's tweaked alright. I'll take pics when my wife gets back with the camera. I'm going to order the ISC aluminum blocks. They're light, strong, and easy to use.

 

[kennertree]

Looks like some big force was on that block to bend it like that. Another question is, if you are lowering logs out of the tree you are in, how do you know the tree (spar) is o.k.? Is it load rated?, spars used in logging have lots of guywires and no one is in the bight when stress is on them. Scary stuff, I like to hammer it down, hack it maybe but safe it is. Think about it.

The log lowered might have weighed 200 pounds, at the most. The reason for the bending of course was the bolt not being threaded in.

 

[clearance]

O.K. pine is pretty heavy wood though. If thats the most anyone hangs, great, hanging big logs involves huge forces that can and have caused spars to fail with sometimes fatal results.