controlling torque

Ned Bulken

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Lakeport NY and/or the nearest hotel
Folks,
I was out in the shop working on my new workbench tonight, and I spaced drilling a pilot hole for one of the lag bolts ... I thought I could out muscle it, but the torque finally out did me. I wound up loosening the opposite end's bolt, spreading apart the leg. which is designed to trap the pipe clamp section as shown here.
leg2.jpg

Would a pair of deck screws hold on either end well enough to counter the torque of driving the bolt home? Or should I use a stouter screw? The deck screws would stay in there, but I think i'd remove anything heftier than that as I don't have many and would need to repeat that procedure on the 2nd leg.

leg.jpg


I gave up when the wrench I was using slipped off of the bolt and flew across the room. at that point I'd had more than enough, and had some computer work to wrap up.
 
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Ned, did you predrill for the Lag Bolts? If not, drill a hole with a "Slightly" smaller diameter bit than the diameter of the lag bolts solid shaft, (not including the threads), and that should relieve the necessity for Extra torque, AND prevent the lag bolt from splitting the wood. Deck screws should hold it in position OK then.
 
Ned, did you predrill for the Lag Bolts? If not, drill a hole with a "Slightly" smaller diameter bit than the diameter of the lag bolts solid shaft, (not including the threads), and that should relieve the necessity for Extra torque, AND prevent the lag bolt from splitting the wood. Deck screws should hold it in position OK then.
Norman,
yep, on 5 out of the 6 holes, I predrilled... 6th one I forgot and paid the price.


Ned, I think the deck screw would be very adequate for the job there. But, I don't know how much you're expecting out of the set up. I have always been accused of "over building".:D

just want it to keep the board from spinning when I tighten the bolt. The Lag bolt is doing the holding together job.. the deck screws would just counter the torque as I tightened the lag bolt.
 
Norman,
yep, on 5 out of the 6 holes, I predrilled... 6th one I forgot and paid the price...

Why can't you drill the hole now? Any time you have to fight a piece, it's a sign that you need to regroup. Even if it requires a bit of disassembly, it'd save you the potential for sore muscles, flying wrenches and split wood. (And if the wood splits, you're gonna have to re-do things anyway.) I'd vote to take a step back and get right instead of trying to muscle your way through (and subsequently messing something up and making for more work for yourself in the long run). ;)

Oh, and to temporarily keep the board from spinning (the torque you're fighting), you can just put a bar clamp on it down by the floor and just step on the clamp. :)
 
Nothing to add to what has been suggested.
But, will say quitting for the day at that point was a good move.
When wrenches start flying, it's time to regroup. Lot of problems get solved for me by just walking away and coming back later.
 
Take a step back several years when there was such a thing as pilot hole and anchor hole. The pilot hole is bored such a size the lag bolt or screw just slips through the hole with no resistance. The anchor hole is bored the size of the screw thread minor diameter or a few thousandts larger. This allows the head to function (pulling 2 members together) as it should with very little frustration.

And of course the anchor hole needs to be bored through both members first.:rofl:
 
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OK, dumb question. Why didn't you clamp it into the workmate it's standing next to?

Astute thought!!:thumb: Also, it is not a sign of weakness to back out of the hole and drill the pilot correctly. (Lag screws are not known for their ability to withstand such torque w/o snapping (then where would you be?)
 
OK, dumb question. Why didn't you clamp it into the workmate it's standing next to?
how do you think I got it in at All? However, It just occured to me how I can better clamp it in there when I get home tonight. thanks though!
Astute thought!!:thumb: Also, it is not a sign of weakness to back out of the hole and drill the pilot correctly. (Lag screws are not known for their ability to withstand such torque w/o snapping (then where would you be?)

Just a sign of stubbornness that I didn't do so up until now. :doh:
 
...Just a sign of stubbornness that I didn't do so up until now. :doh:

In my experience, I've lost more time in the shop fixing problems from taking "shortcuts" than any other single issue. ;)

We seem to never have time to do it right, but we always seem to find time to do it over.
 
Mark to the rescue, his impact driver made short work of fixing the one leg, and making its twin. Got both of them assembled, and the holes drilled for the cross brace, I've got a half day at work tomorrow, so I should have all afternoon to play in the shop!
 
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